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By Russ Finley on May 27, 2015 with 65 responses

Did Tesla Just Kill Hydro Electric Power?

Thanks to Tesla’s new battery packs, can we not only stop building more hydro electric dams, but also remove the existing ones to save what remains of the last river ecosystems, restore the world’s salmon runs? Unfortunately, the answer is no. My sarcastic title was inspired by an article written by Jeff McMahon for Forbes titled: Did Tesla Just Kill Nuclear Power?

 piechart

The inanity of debating the displacement of nuclear energy (which provided 63% of our low carbon electrical energy last year) instead of coal with wind and solar …boggles the mind.

Tesla’s new packs come in three flavors …and many attractive colors. The 7kWh pack for solar panel storage can purportedly be charged 5000 times. The 10kWh pack for emergency use can be charged 1000-1500 times. These are both called PowerWalls. There is also a 100kWh, $250/kWh, industrial version called the PowerPack.

Being able to buy retail, what is essentially a giant power tool battery pack, is a first. What use they will be put to, only the market can tell. Whether or not Musk can create a market for them, only time will tell.

An acquaintance of mine asked what makes Tesla’s new batteries so great and was surprised to learn that Tesla does not make batteries. They assemble Panasonic (or batteries from one of the other battery manufacturers in Japan, Korea, or China) into packs with battery management circuitry to control charging and discharging, very much like the power tool battery packs found at Home Depot …writ large.

He then asked why they are so much cheaper than any other battery pack and was surprised to hear that they aren’t. The battery pack in the Nissan Leaf sells for about 34 and 64 percent less4) per kWh than the 7 kWh and 10 kWh PowerWalls respectively.

When I told my neighbor that it would cost me well over a million dollars to use Tesla’s packs to go off grid he didn’t know what to believe, and I don’t blame him. You’ll see why later.

Below I parse transcripts of Elon Musk’s PowerWall presentation. Like most things in this world, reality is a matter of degree. Rather than rate Musk’s comments as true or false (a step function), I will give each one a veracity (conformity with truth or fact, accuracy) score. I’ll calculate the average score at the end of the post. For example, a typical politician may average a veracity score of about 3 out of 10 any time his or her lips move, a televangelist, maybe a 2 out of 10. A score of zero indicates not a grain of truth to be had. A score of 10 would indicate a cold, hard, fact. They are of course, arbitrary, so feel free to make up your own.

PowerWallTrophy

And if you look back against that wall you’ll see a whole bunch of them as well in different colors so you can pick your favorite color, and it looks like a beautiful sculpture on the wall.

Veracity score = 8 out of 10.

The $71,000 Tesla Mosel S sedan is, by dint of its price, a coveted status symbol. Few, if any, of the individuals who signed up for a Tesla PowerWall to hang on their wall, have a need or use for it, other than as a status symbol by proxy. I gave this remark an eight because beauty (as well as its close cousin, status) is in the eye of the beholder. To me, the PowerWall looks like what it is; a shiny plastic cover over a pack of Panasonic batteries that are about as practical in an American home as a bowling trophy. I’ll explain why, later.

You can actually go, if you want, completely off grid. You can take your solar panels, charge the battery packs and that’s all you use. So it gives you safety, security, and it gives you a complete and affordable solution. And the cost of this is $3,500 (wild applause) … So, this is a good solution for homes and perhaps for some small commercial applications.

Veracity score = 1 out of 10.

This is where Tesla devotees will begin twisting the definition of “completely off grid” and possibly “affordable.” But, assuming we mean “disconnect the two wires coming to your house” consider that it would take about twelve of these packs, worth about 12 x $3,000 = $36,000 (sans loan interest, cost of solar system, and subsidy) just to back up a solar powered average American home for three consecutive rainy days. And because all of your neighbors are also being rained on, the grid and all of its power plants have to be there ready to supply everyone if there are four consecutive rainy days.

 You can’t disconnect from the grid without risking running out of power and somebody has to pay to maintain that grid. It would take well over a million dollars worth of Tesla’s battery packs (in addition to tens of thousands of dollars worth of solar panels) for me to replace the power flows that I currently receive from those two wires attached to my house. That’s because solar panels on my roof can’t generate enough power for my house for half of the year and I would need enough batteries to store six months worth of short fall. See the spreadsheet below.

Costofbatterybu

After seeing the results of my above spreadsheet, I went looking on the internet for corroboration and found it here. His calculations showed a $780,000 cost at my latitude for a roof with optimal inclination big enough to hold the necessary solar panels. See also Footnote 6.

One problem with solar is that there is no “one size fits all” solution. Location, total electricity consumption, how much is used at what times of day (home load profile), the orientation, size, and shape of roof, are different for just about every house.

I live in a modest sized home by American standards, at approximately 50 degrees latitude and consume roughly the American average amount of electricity annually. Even though I own an electric car, our electric bill is slightly lower than the American average.

LeafToHome

There already is a system that uses the battery pack in the Leaf for the same purposes as the PowerWall. I wrote about it three years ago. Read: First Vehicle to Home Power System in North America.

The Leaf system provides a large DC to AC  inverter needed to use the batteries to power your home, as well as the ability to charge the car from either solar panels or the grid, and of course, instead of buying extra batteries, you use the ones you already have in your Leaf.

So, with 160 million PowerPacks you can transition the United States [to use solar with Tesla battery packs for all electricity generation].

Veracity score = 1 out of 10.

Holy cow. 160 million PowerPacks is one for every other American. At $25,000 per pack1), these batteries alone would increase the average annual residential electric bill from about $1,322 to $2,9272), and that’s without taxes or installation costs. And because “…most of that area is gonna be on rooftops” I would need to add the $73,0003)/25 = $2,934 per year annual cost of having solar installed on my roof to charge those battery packs. I would be paying annually $5,861 per year, which is quadruple the average American electricity bill.

And all of those calculations are assuming that the 160 million PowerPack number has any bearing in reality, which it doesn’t. As I showed earlier, it could actually cost hundreds of thousands per household (depending on latitude) to go off grid using these batteries.

You can basically make all electricity generation in the world renewable and primarily solar …And then, going a little further, if you wanted to transition all transport and all electricity generation and all heating to renewable you need approximately 2 billion PowerPacks.

Veracity score = 1 out of 10.

OK, that’s one $25,000 PowerPack for every 3.5 people and never mind what it will cost them to purchase the solar panels, inverters and on and on as well. According to the World Bank, “Almost half the world — over three billion people — live on less than $2.50 a day.” Who is going to pay for all of these batteries, assuming Tesla’s estimate has any bearing in reality, which, as I said earlier, it doesn’t.

Now that may seem like an insane number

Veracity score = 10 out of 10.

The number of cars and trucks that we have on the road is approximately 2 billion and every 20 years approximately that gets refreshed because of a hundred million new cars and trucks made every year.  So the point I wanna make is that this is actually within the power of humanity to do. We have done things like this before. And so, it’s not impossible, it is really something that we can do.

Veracity score = 2 out of 10.

He’s asking everyone on the planet who can afford a car, to come up with enough money to buy the equivalent of several more cars in addition to the one they can afford, and again, this is assuming Tesla’s estimate has any bearing in reality, which, it doesn’t.

The fact that it’s wall mounted is vital. Because it means you don’t have to have a battery room.

Veracity score = 2 out of 10.

 Being wall mounted may be vital to displaying a trophy, but certainly, it could also sit on the floor in a closet somewhere, or in the case of the Leaf home power system mentioned earlier, in your car.

…solar panels and batteries, it’s the only path that I know that can do this and I think it is something that we must do and that we can do and will do.

Veracity score = 1 out of 10.

Considering that virtually all grid storage today comes from  pumped hydro, obviously, selling billions of his batteries isn’t the only path (assuming that it even is a path). It all comes down to cost.

Now the issue with existing batteries is that they suck. They’re really horrible. They’re expensive. They’re unreliable. They’re sort of stinky, ugly, bad in every way, very expensive.

Looking around my shop, I found ten power tool batteries (six of which power my electric bicycle) and a dozen or so batteries in the rest of my home for cell phones, cameras, laptops, etc, etc. Not a one of them fit his above description. They are mostly lithium chemistry. He is referring to lead acid batteries, which, other than for starting cars, have already been replaced for pretty much every other application. They are still used in cars because they are still the cheapest for that use (intermittent bursts of high current with no deep discharge).

So we have to come up with a solution. That’s the missing piece, that’s the thing that’s needed to have a proper transition to a sustainable energy world.

Veracity score = 5 out of 10.

We don’t yet have an affordable non-fossil fueled power source that can fill in the gaps for wind and solar. We do have a non-fossil fueled power source that could do that if it were cheaper than using fossil fuels–nuclear with hydro storage. The whole key here is the word affordable, of which, his batteries are not.

If you’re thinking about buying a battery, what does this provide you? Well, it gives you peace of mind so if there’s a cut in the utilities, you’re always gonna have power. Now you don’t have to worry about being out of power if there’s an ice storm.

Veracity score = 5 out of 10.

One of these $3,500 battery packs (+ installation and inverter) = $7,140 can keep your lights on for part of a day in the event of a power outage. But then, there are dozens of much less expensive ways to deal with temporary occasional power outages.

And very importantly, this is gonna be a great solution for people in remote parts of the world where there’s no electricity wires. Or where the electricity is extremely intermittent, or extremely expensive. So people in a remote village or an island somewhere can take solar panels, combine it with the Tesla PowerWall and never have to worry about electricity lines.

Veracity score = 3 out of 10.

Solar with batteries is already a solution of sorts for some of those people, who live in sunny enough places. Will a modestly lower battery cost than the lead acids they now use make much difference? Those impoverished communities might be able to afford to keep the lights on later at night, or watch television longer, but because this is such an expensive means of producing energy compared to what we pay for energy today (as demonstrated earlier in my post), it can’t scale to create economy-growing, industrial levels of energy.

And in fact I think what we’ll see is something similar to what happened with the cellphones verses landlines where the cellphones actually leapfrogged landlines.

Veracity score = 5 out of 10.

There is nothing new here. Solar with batteries are already being used in these places. Replacing $150 worth of lead acids in a village with say, ($428/$600) x $150 = $107 worth of lithium will not make much difference in their lives.

Conclusion:

  Average veracity score = 3.9.

1280px-Greenwashingcard

Hotel Greenwashed laundry card

Tesla is trying to create a market for its battery packs under the auspice of saving the environment. It’s a tried and true technique called greenwashing.

280px-Roadster_2.5_windmills_trimmed

The $100,000 Roadster and the $70,000 Model S were not conceived as a means of saving the environment. The big battery makers will sell to anyone they want, not just Tesla.

ReservePowerwall

ThankYou

The tens of thousands of orders for these packs are actually tens of thousands of people curious about what happens when they click the “order” button on the Tesla website. You are then asked to leave your contact information (as I did) so they can get back to you in a year or so to see if you really want to buy a pack when they have one to sell (which I don’t).

This “click a button to order” idea was used by Nissan for the Leaf but you had to put a $90 deposit down to show that you were serious.

Lithium batteries have already become ubiquitous. Tesla has had nothing to do with that fact. As my spreadsheets show, the PowerWalls have little practical use in a typical American home, with or without solar, but, like the Hummer, or any big, shiny, red truck that never hauls anything, this won’t stop some people from buying them. Tesla’s current business model can be summed up as selling expensive electric sports sedans to the wealthy. It’s a niche market that no big automaker has bothered to enter. Without a competitor for market share, Tesla has been able to charge whatever it costs to produce the car. The fact that I can purchase a Nissan battery pack for a third to two-thirds less per unit energy than the PowerWalls suggests that if a market for large battery packs emerges, Tesla will face real competition for the first time.

Footnote 1): $250/kWh x 100 kWh = $25,000.

Footnote 2):

Interest on $25,000 loan for 14 years at 4% = $7,263

  • 5000 cycles/365 cycles/year = 14 year battery lifespan.
  • $25,000 + $7,263 = $32,263
  • $32,263/14 year lifespan = $2,305 per year paid by every other American for those 320 million Americans/2 = 160 million batteries.

 160 million PowerPacks is one for every other American. Assuming that the cost is born not by every other American, but by all Americans, that would equate to about $2,305 /2 = $1,152 per person. Using 2.54 persons per household leads to an annual bill per household of 2.54 x $1,152 = $2,927. The average residential annual electric bill today is about $1,322.

Footnote 3):PanelCosts

NRELcosts

NREL solar cost estimator

Footnote 4)

percentdiff

Cost of a 21 kWh Nissan Leaf battery pack = $5,500.

Cost of two 10 kWh PowerWall battery packs connected in parallel for a total capacity of 20kWh~ 2 x $3,500 = $7,000.

Cost of three 7 kWh PowerWall battery packs connected in parallel for a total capacity of 21kWh ~ 3 x $3,000 = $9,000.

This isn’t an exact apples to apples comparison because the PowerWall also contains a circuit board to control DC flows into and out of the pack (just like any lithium power tool battery pack does).

Footnote 5)

Average  American home uses 10,000 kWh per year.

10,000 kWh per year / 365 days per year = 27.4 kWh per day.

27.4 kWh per day / 7 kWh per battery pack = 3.9 battery packs per day

3.9 x 3 rainy days = 12 battery packs.

12 x $3,000 = $36,000

Footnote 6)

NRELcostsMonthly

  1. By Pavan Devatha on May 27, 2015 at 9:57 pm

    it might not make sense in america, but the economics works out well in india. Here the sun shines nearly 8 months of the 12 and even in the rainy season, we get good sunlight for about 6 hours.

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    • By Russ Finley on May 27, 2015 at 11:40 pm

      it might not make sense in america, but the economics works out well in india.

      For the Tesla product of or the Nissan product? Where did this market suddenly come from?

      From the article:

      As the link below from the above article shows, solar is vastly more efficient if you live near the equator when it comes to seasonal storage. If you use half of the American average, as Western Europe does, it calculates a cost of about $40,000 to use these with a solar system (optimal roof orientation etc). If you use a quarter of the American average, then $20,000 (cost scales). If I lived in a grass hut in Hawaii and only needed to charge my diode lights and cell phone when not surfing, one of these packs with solar panels would be like killing an ant with a sledge hammer.

      http://euanmearns.com/how-much-battery-storage-does-a-solar-pv-system-need/

      http://www.energytrendsinsider.com/wp-content/uploads/2015/05/LeafToHome.jpg?00cfb7

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      • By Mike on May 28, 2015 at 12:53 pm

        How did you get the $40,000 system cost? I’m not seeing anything in the linked article to derive that.

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        • By Russ Finley on May 28, 2015 at 2:01 pm

          $17.5K for batteries (sans installation) + $15K for solar system = $32.5K. Assume 10% sales tax, for roughly $36K. Solar city will install a single PowerWall for $7.5K -$3.5K = $4K , so add another $4K for $40K.

          And keep in mind his conservative simplifying assumptions. These are just rough numbers to convey the impact of latitude on seasonal storage.

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          • By Mike on May 28, 2015 at 2:15 pm

            Ok, thank you. It will be interesting to see how the costs and efficiencies change (for both generation and storage) and how much household demand changes in the next few years.

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  2. By Forrest on May 28, 2015 at 9:46 am

    Agree with your post. Wasn’t the most cost effective off grid battery was the lead acid, such as the golf cart battery? I see the big box stores have plenty of deep cycle “marine” batteries in stock with no such lithium battery replacing the choice. Mobile applications with weight restrictions require lithium, but as you post the lead acid battery preferred for common applications per low cost. It’s popular for homeowners to have a car or deep cycle battery on the shelf next to inverter for back up power needs. Lights and TV have extremely low power needs.
    The swipe at TV Evangelist entertaining if one is angered at their insinuations of being held accountable. Don’t think the country troubles lie with to much moral code or listening to Billy Graham ministries.
    We should all hope, the country doesn’t abandon the leading power source of low cost and friendly power of hydro. Don’t think other countries would follow that foolish lead. Not much rare earth metal within hydro power. Didn’t you justify the Leaf and heat pump per hydro power? Our dams increase property tax revenue, minimize spring flooding, utilize for power storage, increase fishery, increase recreation, increase tourism, etc. The majesty of river ecosystem about the same within the dammed up waters. Our dams also have the character of river ways flowing into the flowage and out of dam sites. Fish spawning occurs up stream on shallow waters (even within the flowage) such as fresh spring water and not upon fast flowing river. I know salmon a different requirement of which we have none. Environmentalist usually in awe of beaver pond aquaculture, but horrified if required to portage a cement dam. Go figure? Around here beaver dams destroy trout habitat as they focus on shallow land that heats up water and promotes sucker, catfish, carp, stunted pan fish, and parasite growth as oxygen content low. The feces of beaver carry a parasite destroying potable water quality. Shallow water of the beaver pond a haven for mosquito larvae. Environmentalist typically play the Native American spirituality card wherein TV Evangelism emotions come to portray the need of untainted nature for the sake of these folks to survive and maintain way of life without mental anguish. Problem around here the sale and operation of otherwise illegal practices, substances, and business upon the reservation meet the need. Some of the hydro plants lay on their land and out of reach of typical regulation loving Environmentalist.

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    • By Russ Finley on May 28, 2015 at 1:17 pm

      As the article said, lead acids are cheaper when used for high current applications that don’t require deep discharge. When it comes to deep discharge, as is the case for solar backup, lithium batteries became competitive within the last few years, as witnessed by the low price of the Leaf pack. Click on the link in my other comment to see other companies entering this field.

      Preserving what remains of nature isn’t a high priority with most people. If it’s going to happen, it will have to save somebody money ; )

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      • By CHEMST on May 28, 2015 at 5:50 pm

        But for a home how would a leaf battery compare in cost with a small bank of lead-acid batteries. I don’t know this, but I suspect that they are much cheaper. My calculations is 120Ah x 12V = 1440Wh = 1.4kWh for the power of a typical car battery. At $70 each, 7kWh would cost 5 x $70 = $350 which is much less than $3000 for the Tesla version.

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        • By Russ Finley on May 28, 2015 at 10:33 pm

          There is a link in my article to a study by a company that sells lithium ion battery packs for solar that compares the costs. It is of course, heavily biased to favor their product but makes some sense. The 50% verses 80% depth of charge for example (page 13). I for one, would like to see lead acid go the way of the vacuum tube. But you are right …when someone comes up with a cheaper but bulkier or heavier battery than lithium, it will supplant it for solar.

          http://pvoutput.org/outputs.jsp

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          • By Forrest on May 29, 2015 at 5:49 am

            I did a search, and found lead acid batteries still own the golf cart powering business. You can purchase lithium and many posts attributing to their superior performance, but when cost vs need hits the purchaser they chose common lead acid. Lithium battery can attain 80% use of charge, but owners of the expensive battery, pay attention to life span charge and attempt to utilize 60%. The battery loses lifespan if sitting for long periods of time at high charge status or low. Lithium and other batteries would take a big hit on service life if sitting months for seasonal need. Lead acid battery, also, owns the electric trolling motor market for same reasons as above. Fork lifts appear to be an excellent leading indicator of advance power for mobile equipment. They went electric battery like a firestorm for typical warehouse use. They aren’t converting to lithium, but converting to fuel cell.

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            • By Forrest on May 30, 2015 at 5:11 am

              I wouldn’t conclude lithium beats lead acid for low cost power storage based on Leaf battery pack. Japanese companies have a habit of subsidizing their new technology as a marketing ploy. They wouldn’t wholesale distribute their batteries for household use. Also, it would have to be a true economic (time value of money) analysis comparison. Because the lithium is more expensive it would indeed need substantial life cycle benefits.

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      • By Forrest on May 29, 2015 at 6:45 am

        One problem with nature shows and those wanting to manipulate public to their ideals, they always claim doomsday and awful humans destroying nature and wonderful government control. Many of the stories of man solving environmental problems go untold. Especially private citizens solutions requiring no taxpayer regs. The health, pollution, wildlife problems occur upon a discovery. Meaning public at large have to gain knowledge, science has to research, and private sector has to solve. So much entertainment and classroom lectures attempt to portray capitalism and profit the culprit. I think that is a red herring as we discover problems private sector usually solves per desire of customers. Note the elephant trade is highly regulated and goes unsolved.

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  3. By gametheoryman on May 28, 2015 at 1:26 pm

    Agree with the major thrust of your argument, but two additional points are important here.

    First, the role of natural gas is important. Where it is produced and one has access from pipelines, including of course almost all of the U.S., natural gas provides the least expensive source of power, both for heat and electricity. This means no bulge in demand from October-March as you indicate above, and the cheapest energy “storage” where pumped hydropower is not available is the storage of extra natural gas power generation capacity. Batteries may make sense as an emergency power source and buying and selling power to the grid, but their costs are now 2-3 times too high.

    In areas without access to natural gas from pipelines, batteries are, or will soon be, efficient to use for buying and selling power to the grid or as an emergency backup. This includes much of Europe, Asia, and South America, starting in the sunniest areas with the weakest grids. Here too, if you are connected to an existing grid, efficiency requires that you stay on it, even if you have rooftop solar.

    Second, batteries are never to be used for seasonal storage, going through one charge-discharge cycle within a year. Much better for daily charge-discharge cycles, either taking advantage of the difference between the low cost power in the middle of the night and the high cost of power in the late afternoon if you are connected to the grid or taking advantage of the difference in your personal net demand between day and night if you are not.

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    • By Russ Finley on May 28, 2015 at 3:32 pm

      …good points. That’s why I gave Musk’s claim that they can be used to go off grid a veracity score of 1.

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  4. By TimC on May 28, 2015 at 2:23 pm

    Very revealing quote from Musk, that solar panels and batteries are “…the only path that I know that can do this…” This shows the kind of echo chamber Musk lives in. Anyone who has been following alternative energy development knows there are many ways to reduce fossil energy dependence, and many of those ways are more practical than solar panels and batteries.

    Most of the gushing reviews of the PowerWall focus on its appearance. But does the appearance of a battery storage unit even matter? Are people mounting PowerWalls in their living rooms? Many businesses have had battery UPS units for decades; they consist of a stack of 12V lead-acid batteries, an inverter, and controller. The whole thing costs maybe $3k installed, and is ugly as can be, but so what? It sits collecting dust in a utility closet or in a corner of the shop; few know and fewer care what it looks like. Why are people suddenly enamored of the appearance of a battery pack?

    Like the late Steve Jobs of Apple or KR Sridhar of Bloom Energy, Musk’s genius is for salesmanship, not technology development. These guys have the unique ability to make people suddenly want something that has been available for years. They can generate lots of headlines and sometimes impressive sales figures, but they are not inventors, and what they produce is not progress.

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    • By Russ Finley on May 28, 2015 at 3:36 pm

      …I wasn’t kidding about the trophy thing. They will be hanging on living room walls. Watch for it.

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      • By TimC on May 29, 2015 at 10:39 am

        Now that I think about it, the living room wall would not be the best place, because only people who enter the house can see it there. It would be better to hang your new PowerWall on the front of the house, where it can serve as both a battery pack and a kind of nameplate. Passers-by could then stop and marvel at the Tesla House, and try to catch a glimpse of the hip green beings who dwell within.

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    • By Alex Johnson on June 12, 2015 at 12:26 pm

      By and large you’re correct, especially with the roadster he didn’t set out to make the most efficient electric car. He made one that looked cool and proved that electric cars didn’t have to be boring. And the same goes with solar panels and these power walls. However, I would have to say that SpaceX is very ambitious and it doing cool new things and really bringing the price of space flight down. Thats way outside the discussions for this forum, but not everything of his is just a sales pitch.

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  5. By CHEMST on May 28, 2015 at 5:38 pm

    What I have always wondered is how the same battery pack can be optimized for a car and a home at once? In a car, the three most critical considerations are the mass (greater mass requires more energy just to move it), the volume (greater volume requires a bigger car and hence more mass to move) and the capacity (which determines driving range). The problem with lead-acid batteries is mostly the mass. They weigh so much that you expend much of the energy capacity of the batteries just carrying them with you. In contrast, in a home, the mass of the battery is more or less irrelevant and volume will at least be a more minor issue. Hence, I would imagine by accepting more mass and volume, one should be able to get more capacity per dollar spent.

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  6. By Jim on May 28, 2015 at 6:41 pm

    Two questions. It appears that your spreadsheet has you buying new battery packs each month. I think that you would only need the amount listed for the month with the most need for power. This would change your calculations greatly. Not the total you have for the year. Second to sure you would need the three days of total power backup as even on rainy days, it is my understanding that the panels still work, just not as well. A rainy day is not dark as night.

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    • By Russ Finley on May 28, 2015 at 7:24 pm

      It appears that your spreadsheet has you buying new battery packs each month. I think that you would only need the amount listed for the month with the most need for power

      If you look at the spreadsheet carefully you will see that April through September generate a surplus (Delta column) that would be used to charge the 395 batteries ready for winter for when you have six months where your solar panels can’t meet your household monthly needs (or charge a battery). When the 28 batteries used to meet the missing 196 kWh in October are used up, there is no way to recharge them until April. You need 60 more charged batteries waiting to supply the missing 420 kWh in November, etc, etc.

      http://www.energytrendsinsider.com/wp-content/uploads/2015/05/Costofbatterybu.jpg?00cfb7

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      • By Jim on May 28, 2015 at 8:07 pm

        Thanks for the reply. It was just a minor quibble. The thrust of your analysis is obviously correct as there is no way one could justify the floor space and cost of over 100 of these batteries for one months need. Basically you are saying that your analysis is taking into the cost of having all the batteries on hand to store the excess power in the warmer months so that they can be used in the winter. So you need to account for the total difference in the batteries for the winter months. Is that 395? Or is that that the total for the year because the batteries from the summer months would not come into that calculation. (The power for the 12 batteries per month in the summer is just in case you need it, not actually used. The ones that are needed to store power for the winter could handle that). Looks like grid connection still the best option for now.

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        • By Russ Finley on May 28, 2015 at 10:15 pm

          Correct. The twelve batteries needed in the summer are not included in the 395 total (see heavy outline in spreadsheet for what belongs in totals).

          Also see if you can spot the two most heavily overcast days in the graph below and note their output:

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          • By Terry on May 30, 2015 at 4:08 am

            Why would you need 395 Power Walls? Don’t you just need the maxima of the delta which is in December of 128 Power Walls? It’s still a lot but the 395 number looks wrong to me.

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            • By Terry on May 30, 2015 at 4:32 am

              Oh, I see how you arrived at that number. If the need of batteries is so great, doesn’t it make more sense to increase the number of PV panels then?

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            • By Russ Finley on May 30, 2015 at 2:50 pm

              …doesn’t it make more sense to increase the number of PV panels then?

              That same point was made in the comment field of the other engineer’s study, and yes, that is yet another of dozens of variables one can play with (reduce energy use, change time of energy use etc, etc). In my case, more panels is not an option because in my calculations I have already covered every square inch of my roof with panels. Adding more panels is cheaper than adding more batteries until you run out of space for panels, and of course, the extra panels are not free and will tend to produce far more power than you can consume annually, even after charging batteries. And even at the equator with no air conditioners, you still need some minimum number of batteries to cover yourself for consecutive heavily overcast days, depending on your power needs.

              The bottom line is that, on average, in the United States, it’s still far less expensive to just use the grid. That is what it was designed to do, provide the lowest cost energy.

              I can see going off grid in a place where your energy is from coal, because you can say that you are reducing GHG emissions, cost be damned. But the cost is not trivial, and maintaining your own power station is not going to be cheap or easy either.

              If you could eliminate your water and sewer bills by digging your own well and installing your own septic system, would you do it or stick with the cooperative grid where all maintenance is done by a third party?

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            • By Alex Johnson on June 12, 2015 at 12:16 pm

              I realize this is mostly through the scope of using solar panels, and maybe the PNW doesn’t have as much wind as the midwest, but it makes more sense to me to do a combined solar/wind generation setup. Especially since the footprint of a small wind tower in the backyard wouldn’t hurt your rooftop solar collection. Unless you have a lot of unused acreage trying to meet the full demand with solar isn’t terribly realistic no matter where you are in my opinion. Like I said, this is through my midwest bias where the windmills almost never stop turning, but I have to think you have some breezes coming off the ocean out there.

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            • By Russ Finley on June 12, 2015 at 3:55 pm

              Do you know anyone with backyard wind who can supply you with real world cost data? Certainly, you would need a lot of spacing between you and your neighbors.

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            • By Alex Johnson on June 12, 2015 at 4:31 pm

              I know of two people that have them, although I’d have to ask them for their data specifically. And as for spacing, it depends on what your height restrictions are and how big of a turbine you plan on putting up. The smaller 400 watt ones are small enough to be mounted on the roof. The larger ones that need their own tower will probably need other permits as well. Either way I’m just saying realistically, if you have any wind in your area it would make more sense to run a hybrid system. But, thats with my midwest bias and around here the average wind speed is 10-15 mph year round. I realize thats not the case across the country.

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  7. By mulp on May 29, 2015 at 12:16 pm

    I gather you live in Seattle where you benefit from big government socialist hydropower, much like France benefits from big government socialist nuke power.

    I think you have cooked your numbers much as Elon Musk has, but then Elon Musk hasn’t done anything new that government didn’t do before, but he’s done it privately, faster than anyone has since Reagan sold America on free lunch economics of not working but just wait for capital gains to make you rich. Plus he has the essence of Edison to get people’s attention with wild claims and then delivering. Sorta like JFK’s almost off hand promise to go to the moon.

    The Powerwall looks to me about the right size to trump prohibitions for net metering feed in to the grid for homeowners. Shift excess power into the evening from a 4KW PV array and you cut your demand for high priced kwh, say the 37+ cent per kwh in Hawaii.

    Run your calculations for Hawaii and see if the Powerwall will save you anything based on the current reality you can connect to the grid, you can have solar, but you can’t feed solar power into the grid because they already have too much solar feeding into the grid already.

    Of course, batteries to store solar and wind are not new,and are more often used as UPS systems where the grid is unreliable. But none of the existing home and commercial battery system suppliers are being aggressive in growing the market rapidly. Elon Musk has given them a gift.

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    • By Russ Finley on May 29, 2015 at 3:39 pm

       I gather you live in Seattle where you benefit from big government socialist hydropower, much like France benefits from big government socialist nuke power.

      Interesting choice of examples. Both WA State and France have some of the lowest electricity rates and GHG emissions in the US and EU grids respectively. Why would someone in those places want to go off grid if it costs more and would not decrease GHG emissions? Ditto for going off your water, sewer, or natural gas grids.

      I think you have cooked your numbers…

      Feel free to point out any errors. The spreadsheets and sources are right there to check.
       

      Run your calculations for Hawaii and see if the Powerwall will save you anything

      Your turn to run numbers. I’d like to see a house in Tucson, Miami, and Maui. Use the NREL solar cost estimator to get an apples to apples comparison. You will need to find monthly energy consumption for each house. I used my home because I have that data.

      Your are right in that Musk is a salesman. He may have increased the market for large packs of Panasonic batteries, but that is not necessarily a good thing when it does not reduce costs or GHG emissions.

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      • By Forrest on May 31, 2015 at 7:19 am

        Regulators will not let you compete with municipal utilities. They will require you to abandon paid for water and sewer systems and hook up to their expensive system. Common utility bill is $50-$75 per month. No one will utilize expensive city water to irrigate lawns around this part of country. If you have well water, not that expensive. Actual costs per my records have non municipal utilities a bargain. Nice to have fresh well water full of healthy minerals as well. I know the piping has no lead or threatened with biological pollution, no chlorine required.

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  8. By Forrest on May 30, 2015 at 5:57 am

    Interesting that you utilized your personal home power needs for the analysis. But, if one were truly attempting to go off grid, you know the homeowner would minimize power needs. They would utilize the most efficient refrigerator, freezer, elimination of AC, NG or propane cooking and water heating, LED lights, gas dryer, wood stove, and gas furnace. Since these appliances sit at the least total cost to homeowner probably a smart move in any regard, unless the grid is powered by hydro as in your case. My two occupant household billed at 10 kWh/day, but if I attempted to go off grid, the space heater would get tossed. One Tesla wall unit would suffice for daily needs. Problem is as your post indicates, our full cloud days can go on for more than a week and usually during largest need of winter. So it would be a futile attempt to go off grid with solar. I can get Kohler emergency generator for $3k that could easily power the house on demand. Fueling on NG the power would cost about 2x that of grid. Source or Modify a heavy duty small diesel single cycle with spark ignition and lower compression for NG. Operate at low noise lower RPM for power generation. Keep the unit within the house to harvest waste heat. Change out the muffler with water heat exchanger and vent exhaust to outdoors. Well, your fuel cost and efficiency magically beats the power company. You could sell power and make money. It doesn’t sound difficult either. It’s all off the self hardware, low tech solution well proven over the years. Yet, Honda and the few competitors that sell this equipment charge an outrageous price as regulations inflict maximum cost to deter any such easy solutions becoming poplar. The same fate inflicted upon the NG home refueling station. Politicians threatened by commercial interests rushed to crush any hope of public having a low cost convenient solution bypassing business as usual. I’ve witnessed regulations time and again utilized to empower corp wealth. Here in Michigan politicians rushed to crush internet sales of auto’s (Tesla) as it bypassed normal profit centers. Same with solutions that compete with utility interests, politicians rush in to crush competition per guise of safety. Micro grid could save consumers a bundle, yet they regulate to death. Ask yourselves, what is the real danger of sharing a water well resource with neighbor? Not much. Can you imagine the low cost and efficiency upon a city block of consumers sharing utilities? Coordinating power needs, production, laying lines and piping for heating, cooling, internet, cable, waste management, crop production, lawn management, timber sales, youth employment, etc. No wonder the wealthy achieve more and the non-wealthy continue to pick up the tab.

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  9. By Forrest on May 31, 2015 at 7:03 am

    Maybe a large proven resourceful business could obtain 4% loan for business use, but I doubt a 14 year non subsidized loan could be acquired by private citizen for nonstandard use. The real ROI requirement to make a purchase would lie much higher. One has many uses for capital for budget purposes, investments, etc. The going off grid project would have high risk per obsolescence, regulations, breakdown, storm damage, insurance, technical help, inferior estimates, loss of battery life, labor, etc. For example by attaching the battery pack to wall it may be taxed within property tax and homeowner would overnight lose all cost savings. Business would need 12% ROI load on the project minimum. Homeowners should have a long list of capital expenses and ROI as competing offers. Take the best first. Adding insulation? Change to natural gas appliances? Wood heat, LEDs, a lower deprecation auto, higher mileage auto, landscape, paint, repair, improvement, recreation, etc. Homeowners often forgo 20% ROI because of laziness, high need of capital, poor knowledge, etc. Saving rate of average citizen dismal for such activities.

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  10. By Raymond Gershon on June 1, 2015 at 10:44 pm

    Plans are to Mass produce the product, there will be a slight waiting period, Only for a short time, 45 days, after that point, supply will be ahead of demand, Thus Prices will drop 25-30%. Their Marketing plan & availability of product will do much better than what was written here. This is their objective, You won’t hear it from the Company.

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  11. By Forrest on June 2, 2015 at 9:24 am

    Tesla should buy out Green Charge Network as they have a business that doesn’t rely heavily on taxpayer subsidy. Green Charge Network utilizes a similar lithium battery pack, “Green Station”, but the battery power utilized to shave off user power spikes and thus saving costly demand charges. These demand charges are found in Texas and California utility companies. Come to find out solar and wind have ravaged the stability of their grid. Power generation and supporting equipment must stay on line per the unreliable power production of wind and solar. This expensive proposition paid for by commercial and industrial customers per the demand charge. The billing follows a complicated formula with variables of supply, demand, season, time of day, power use, and monthly use. Green Charge Network benefited per government grants wherein the development of software could short circuit the normal smart meter billings. The Green Station smart controller samples power consumption second by second and can switch to battery power to whack off peaks of costly rates that are utilized by utility companies to base line expensive demand charges. I know it’s a bit of trickery enabled by subverting intentions of utility company, but the “Green Station” saves a load of utility expense. Home owners (voters) are not subject to demand charges as they would soon turn their back on green power choice. Instead the real cost of green power is hidden away in ever more costly products and services. Thank you tricky politicians.

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  12. By John Thompson on June 8, 2015 at 11:19 pm

    More than a hundred years ago, the pioneering genius Nikola Tesla
    presented his vision of a global power network that did not require
    wires and could transmit electricity across the world with negligible
    power loss. Russian physicists have closely examined Tesla’s concepts and have come close to creating the technology for global electric wireless network.Take a look at this http://igg.me/at/globalenergytransmission/x and this http://globalenergytransmission.com/index.php/en/latest-news/27-examining-working-principle-of-tesla-tower

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  13. By ReaMuch on June 11, 2015 at 2:51 pm

    The energy cost for the Powerwall battery purchased directly from Tesla is app. $.10/kWh over the life of the battery (source Clean Technica analysis). Therefore, the battery is only useful in places like Australia where average electricity prices are often above $.25/kWh or for commercial/industrial applications that have high demand charges or for the small % of people who live off-grid and can afford such batteries. Also, anyone seriously considering going off-grid would reduce energy use significantly beyond on the on-grid lifestyle, as displayed in your example.

    Nissan won’t sell you a Leaf battery by itself for energy storage needs. It has to be installed on a Leaf and the old battery is traded in. That said, a used Leaf could be a low cost battery storage option with the right additional equipment.

    You didn’t include the 30% federal renewable energy tax credit in your solar cost estimation. Why?

    Those in the PNW are fortunate to have low cost hydro energy available. When I run the NREL PVWatts solar estimator, I get $.16/kWh (also east aspect- 13% penalty) which is exactly the same as our coal fired utility’s electric rate for new customers or for those who PV net meter. We’re on a grandfathered electric only plan and the unit rate for all of last year’s use was $.128/kWh (includes sales tax). We will be installing app. 8kW of PV net metered and a DIY solar thermal water heating system to cover all of our energy needs.

    Backup power? We might go with a small in-home Li ion or Na ion system when prices drop further. For the time being, several inexpensive inverters are available that “plug” into either the ICE battery or the Leaf battery.

    I do think you’re underestimating the volume of scale cost reductions that will come about with Gigga factories for both batteries and domestic PV panels. Whether or not consumers share in such cost reductions remains to be seen.

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    • By Forrest on June 11, 2015 at 4:50 pm

      What you post, “therefore, the battery is only useful in places like Australia where average electricity prices are often above $.25/kWh”, read this Aussie’s number crunching options,

      http://www.lifehacker.com.au/2015/05/tesla-powerwall-crunching-the-numbers-for-an-australian-suburban-home/

      Doesn’t sound good.

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      • By ReaMuch on June 11, 2015 at 5:36 pm

        I guess you didn’t go to the Clean Technica article I mentioned. Search this on Cleantechnica dot com:

        Tesla Powerwall & Powerpacks Per-kWh Lifetime Prices vs Aquion Energy, Eos Energy, & Imergy

        Now the Powerwall price from Tesla will be slightly higher in Australia with shipping and exchange rates, but the math in the article you reference is wrong for many solar customers who already have solar panels installed and also have an inverter.

        I hope this clears up the confusion.

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        • By Forrest on June 12, 2015 at 8:38 am

          The Clean Technica article a poor analysis of cost. True, any evaluation depends on one’s personal circumstances. The author doesn’t document much of the data. Assumptions are listed, such as an ideal $.35 per kilowatt cost. The $.10 per kilowatt cost for the Powerwall is disingenuous. No customer could purchase a unit at such a price and to utilize the wholesale price is just an exercise in promotion as the price may be unattainable per purchase restrictions of Tesla. They are famous for self promotion and suspect that publish price for such purposes. Same for Nissan that often subsidize new technology. The analysis assumes zero cost (over capacity) of solar system waste power, a rare situation, indeed. Don’t think an investor with such expensive hardware would let the system produce waste power.
          Typical solar install cost justification in which the owner hooked up per benefits of grid power usually able to receive retail price for solar power sales to offset meter consumed power per PURPA regs. This is a subsidy for solar benefit and promotion and will end as rate payers will get angry once realizing they are picking up the bill for neighbors solar install. There is no time value of money allocated to such a purchase. This ROI figure is not close to investment bond rate as capital investments is riddled with risk for such things as obsolescence, fire, insurance, maintenance, bad accounting, insufficient funding, utility regulation change, property taxes, etc. I utilize 1% per month before considering such a capital purchase. So, a $5,000 investment with little salvage value must produce $50/month savings, after accounting for the depreciation and all other costs. The install cost, sales tax, insurance costs, and maintenance cost must be added to the analysis. To infer zero cost to your solar, since the decision to purchase already made is disingenuous. This would be like purchasing a new car and assuming it cost the purchaser nothing. You already have the car so IRS should only allocate fuel for your business use, right? Since you already have the car you can account all avoided taxis fees to pure savings, right? You would lose money quickly with such thinking.

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          • By ReaMuch on June 12, 2015 at 11:54 am

            You probably know that with new developments the facts often take several days to be known to all. Such is the case with the Powerwall and the news outlets and blogs.

            The retail price of the Powerwall 7kWh battery is $3k for the USA (Search: “Let’s Get Straight: Tesla Powerwall DOES = $3,000″) This includes a BMS and a DC to DC conversion. It appears that this battery will work with some grid-tied string inverters with minimal effort. It’s not designed for micro-inverter systems.

            The point- this battery sets a new lower price standard. Let the competition drive the price lower.

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            • By Forrest on June 13, 2015 at 5:05 am

              If so, it would be prudent to wait upon the investment. The industry appears to be in a high rate of innovation and change that will obsolete your system quicker. Double the ROI for such risks.

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          • By ReaMuch on June 12, 2015 at 12:20 pm

            PVWatts cost of electricity generated by system assumes:

            The Cost of Electricity Generated by System is the system’s levelized cost of energy. It is the cost of owning, installing and operating the system over its 25-year life, assuming a 2.5% annual inflation rate and 8% real discount rate.

            Personally, my Life Cycle Energy Savings Calculator shows an internal ROR of 10% for installing solar on our home. This assumes 25 year life, PVWatts production est., 4.5% utility inflation rate, 3.5% interest on a 10 year loan to buy panels, M&O costs for 10% failed micro-inverter and additional homeowner’s insurance (5% inflation rates incl.),, and a discount rate of 3.0% (app. equivalent to a 25 yr. USA government bond).

            Some might argue that a 3.0% discount rate is too low. Compared to what? Corporate stocks and bonds? Yea right. When the financial house of cards falls all such investments will face a big downward price adjustment. Hard assets like rental properties, agricultural land, etc. are often better, but not as easy for the average person to invest in. Past performance of a financial investment is not a guarantee of future performance. Please show me where any stock or corporate bond guarantees a 25 yr. rate of return of 1% per month. Crickets.

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            • By Forrest on June 13, 2015 at 5:02 am

              I hope your numbers are accurate. You did your homework! Your story sounds like what I read in newspaper after stock market decline. A local university prof took his retirement $ out to do as you describe per untrustworthy stock market. He was going to be self sufficient and enjoy cheap power upon retirement. The paper had a big writeup on the virtues, wisdom, and alternative benefits as you post. It was a major blowing sunshine article to convince readership they can do much better with alternative energy. The ending paragraph described the prof’s new found alternative lifestyle. First he ended up spending close to $30k as he was forced to purchase a mini-turbine generator since Michigan can go for weeks with little sunshine in winter season. He converted his household per minimal power requirements including expensive fridge. He heats with wood, probably to save from powering furnace fan motor. He must of relied on NG to dry clothes and cook . That would be a smart move and first choice of low power users per low cost and environmental benefits. Same for wood heat if not destroying woodlands. Anyways the guy described a lifestyle of ever present concern of power use and battery charge. His wife couldn’t use the hair dryer or curler and went to work with wet hair to use the “free” university power. He still needed a back up fossil fuel generator for low power days. I bet his cost savings could be thrown out the window per present day improvements that obsoleted his solution not the less the huge bull market return he could have enjoyed!

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            • By Forrest on June 13, 2015 at 5:18 am

              Another newspaper story of local greenhouse company that invested over $100k in solar power. Same blowing sunshine format and all the “free” money available. Later I read the business was in a lawsuit attempting to regain losses from property tax hit. They ended up losing money on the venture. Another similar article with cost effective solar. One had to finish the article to determine the company signed a PPO with local utility to sell power at something like $.50/Kwh rate. The company utilized low cost grid power as they couldn’t justify using their own expensive solar power. The business liked the deal and decided to greatly expand solar power production. Utility company refused to pay and they went to court. Judge decided in favor of business, so again solar highly profitable. You need to get this business contract. So can we expect our utility rates to go down with more solar power? It’s free energy, right?

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          • By ReaMuch on June 12, 2015 at 12:26 pm

            You need to accept that net metering is here to stay until there is full electric utility reform. The crony right wing is being knocked down by their own party on this attempt to eliminate it.

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    • By Russ Finley on June 12, 2015 at 3:42 pm

      You didn’t include the 30% federal renewable energy tax credit in your solar cost estimation. Why?

      There are also many State sponsored subsidies.You can get a good deal while a subsidy is in place, as we did when we bought our Prius, but that subsidy (like all subsidies are supposed to do) went away, and everyone after us paid full price. So, when talking about actual costs to society, I don’t want to sugar coat them by subtracting a temporary subsidy from the total cost.

      I do think you’re underestimating the volume of scale cost reductions
      that will come about with Gigga factories for both batteries and domestic PV panels.

      I don’t recall making any estimates about future costs. Certainly, I have enough home maintenance and complexity in my life without adding panels to my roof, an inverter in my basement, and batteries on my wall.

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      • By ReaMuch on June 12, 2015 at 4:00 pm

        By not including the available federal tax credit, you give the impression of being disingenuous in your calculations. The same goes for claiming that you can buy a Leaf battery pack. No you can’t. You can only buy a Leaf battery pack installed on a Nissan Leaf. Big difference.

        I assume that you don’t have any agenda against solar PV or Tesla.

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        • By Russ Finley on June 12, 2015 at 4:55 pm

          Strawman arguments don’t work in comment fields. I never said that Nissan sells battery packs for home use. I simply showed how much cheaper their battery packs are than the Panasonic pack assembled by Tesla. Telsla better hope that Nissan does not start selling packs for home use ; ).

          Should I have also listed all state and local incentives to avoid the accusation of giving “the impression of being disingenuous” in my calculations?

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          • By ReaMuch on June 12, 2015 at 5:30 pm

            You wrote ” The fact that I can purchase a Nissan battery pack for a third to two-thirds less per unit energy than the PowerWalls…”

            You are comparing a replacement Nissan Leaf battery pack installed in a Nissan Leaf and designed for electric car use to a standalone Tesla battery pack meant for home electricity use. It’s not an apples to apples comparison.

            If they are available to you, why not?

            You made your point by not including the federal solar tax credit in your calculations. That was the first thing I spotted in your math. it’s an odd choice for someone promoting clean, non polluting, low carbon energy.

            Do you tell people when they ask about the Nissan Leaf or any electric car that they shouldn’t consider the federal tax credit in their buying decision? I hope not.

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            • By Russ Finley on June 12, 2015 at 8:56 pm

              You are comparing a replacement Nissan Leaf battery pack installed in a Nissan Leaf and designed for electric car use to a standalone Tesla battery pack meant for home electricity use. It’s not an apples to apples comparison.

              From my article:

              This isn’t an exact apples to apples comparison because the PowerWall also contains a circuit board to control DC flows into and out of the pack (just like any lithium power tool battery pack does).

              ReaMuch continues:

              You made your point by not including the federal solar tax credit in your calculations. That was the first thing I spotted in your math.

              I made several points. My main point was that it would cost me well over a million dollars to go off grid with BatteryWalls. You failed to spot in my math the fact that I didn’t include the cost of the solar system in that calculation.

              It’s an odd choice for someone promoting clean, non polluting, low carbon energy.

              …says the guy promoting solar who has chosen not to mention that the tax credit expires at the end of next year.

              Do you tell people when they ask about the Nissan Leaf or any electric car that they shouldn’t consider the federal tax credit in their buying decision? I hope not.

              From my article:

              The $100,000 Roadster and the $70,000 Model S were not conceived as a means of saving the environment.

              No mention of state, local, or federal tax credits.

              http://www.energytrendsinsider.com/wp-content/uploads/2015/05/Costofbatterybu.jpg?00cfb7

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  14. By ReaMuch on June 11, 2015 at 3:51 pm

    The CAGR for coal fired electricity prices from our IOU has been 4.5% per year over the last 16 years. You fail to mention electricity cost inflation from your supplier. I assume it’s low due to free fuel (water). If it’s an IOU, then investors will be paid their 5%-10% dividends every year, management and employees will get their raises, etc. The only way this will stop is when ratepayer say no. If that happens, IOU downsizing will begin and utility reliability will fall.

    Doing a cash out refinance (to pay for PV panels) for 10 years at 3.5% fixed makes financial sense for us. Even cashing out of some 401K money makes sense for the conservative investor. What regular investment other than PV is guaranteed to return 4.5% for 15-30 years? Answer- NONE (energy efficiency aside). 20 year USA federal bonds are a close risk comparison (apples to apples), but the current yield is only 2.96%. Comparing stocks and bonds to PV is not logical from a risk standpoint.

    Off topic to Li Ion batteries, but your solar cost example is not typical for most of the USA.

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    • By Forrest on June 12, 2015 at 8:23 am

      Funny, my utility claims coal power the reason for minimal cost increase of rates and that if forced to abandon the power plants rates will spike. Also, they claim if forced to utilize solar and wind, rates will do likewise. Also, my nonprofit cooperative has the most expensive rates as compared to neighboring IOU supplier. I am legally restricted to purchase from non compete supplier with rates 40% higher. The competition utilizes coal and nuclear. Hawaii has an ideal situation for alternative power and should attempt to replace imported diesel fuel power plants. Tropical sunshine and extremely expensive rates work well for alternative power. Good for them. I don’t think they should use wind turbine as the Island State is home to most of endangered bird wildlife of U.S.. The main island of Hawaii should have been nuclear decades ago. This still would be the most sensible solution for base load power. Those nuclear batteries utilized on smaller islands.

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      • By ReaMuch on June 12, 2015 at 11:30 am

        Propaganda flows freely in the USA from IOUs and poorly run electric coops and municipal utilities.

        My numbers are real, as I have lived in the same house for 16 years, and they show that coal fired electricity is not cheap and IOUs will gouge the captive ratepayers when they have crony politicians in their pockets. Public unrest will eventually stop this behavior.

        The green tea party has put the crony Republicans in their place, for now, and net metering is here to stay until there is comprehensive utility reform. It’s funny to see the right side of the political spectrum implode, as it should. Back to the center for the USA!

        Full utility deregulation is not the answer though, because studies in Texas have shown that in deregulated utility markets customers pay 31% higher rates than in nearby properly regulated utilities. Of course this makes sense because no money is wasted on dividends, advertising, corporate foundations (management picking charities for its captive ratepayers to fund), overpaid management, etc. with the “well run” municipal utilities.

        New nuclear is a boondoggle and is dead due to high install price (see Georgia) and externalities. The same goes for carbon capture “clean” coal. The old nuke facilities will run until major investments are required and then they will shut down.

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        • By Russ Finley on June 12, 2015 at 3:06 pm

          IOUs [investor owned utilities] will gouge the captive ratepayers when they have crony politicians in their pockets.

          … then you can’t escape by investing tens of thousands into solar panels because your corrupt politicians would simply tell the utility to increase your grid use fee until they get their money. This is why you want to avoid using conspiracy theories to support an argument. Your debate partner can create counter conspiracy theories that are just as valid/invalid, provable/unprovable.

          New nuclear is a boondoggle and is dead due to high install price (see Georgia) and externalities.

          Translation: historically low fossil fuel prices (natural gas) are presently cheaper than new nuclear in the United States. That won’t last.

          The same goes for carbon capture “clean” coal.

          Somewhat disingenuous to compare nuclear, with over half a century of proven, reliable, cost effective low carbon energy, to an untested hypothesis that has never been deployed at scale. (carbon capture and storage).

          The old nuke facilities will run until major investments are required and then they will shut down.

          True, because that is what is supposed to happen to old power plants, nuclear, wind, gas. New nuclear will be increasingly cost effective once the cost of natural gas gets high enough.

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          • By ReaMuch on June 12, 2015 at 3:48 pm

            In our state (IN) it’s a fact about the crony relationship between politicians, the public utilities commission, and the IOUs. All one has to do is look at the substantially lower electric rates for coal fired electricity in KY or at many municipal utilities in IN to prove this point.

            You can escape possible discriminatory grid access fees by signing a Net Metering contract. Of course, the utility could still increase grid access fees for everyone. Most of my middle class neighbors have disdain and disgust for our IOU. Because of increasing public resistance, the IOU may not have the ability to increase fixed fees in the future.

            I disagree about new nuclear ever being cost effective if all externalities are accounted for, especially compared to renewable energy combined with efficiency improvements. Also, decentralization of the grid is more compatible with DG.

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            • By Russ Finley on June 12, 2015 at 4:46 pm

              In our state (IN) it’s a fact about the crony relationship between politicians, the public utilities commission, and the IOUs.

              I grew up in Indianapolis, so, I am hesitant to disagree with you on the level of political corruption. However, if you go to the EIA website you will get a feel for how wildly rates vary from state to state. The reasons for that variation are many and complex, I’m sure, but only partly because of incompetency and political shenanigans.

              I disagree about new nuclear ever being cost effective if all externalities are accounted for, especially compared to renewable energy combined with efficiency improvements. Also, decentralization of the grid is more compatible with DG.

              What does DG stand for? Efficiency improvements are good regardless of energy source, so we can’t really use then to support just one energy source.

              Your hesitation about nuclear is because of false information about external costs. If you made a concerted effort to find accurate information you seem like the sort that might change your mind based on the facts. I’ve seen no competent study claiming that wind and solar can do it all. In fact, a team of Google engineers assigned to this problem concluded that even with nuclear in the mix, we don’t have the weapons to fight climate change.

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            • By ReaMuch on June 12, 2015 at 5:38 pm

              DG is distributed generation, or energy generation produced right where it’s consumed.

              I’ve fully researched the costs associated with nuclear energy and I still disagree with you.

              I mention energy efficiency because I believe that energy use can drop substantially and still support a functioning society. Lower overall energy use is compatible with all forms of generation, but it makes 100% renewable energy easier to accomplish.

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            • By Russ Finley on June 12, 2015 at 7:32 pm

              DG is distributed generation

              That’s what I thought but it seemed a redundant thing to say in the sentence: “Also, decentralization of the grid is more compatible with distributed generation.” Distributed generation is by definition decentralized.

              I’ve fully researched the costs associated with nuclear energy …

              We can’t both be right.

              Lower overall energy use is compatible with all forms of generation, but it makes 100% renewable energy easier to accomplish.

              That belief is the core of the problem. I have yet to see a credible study showing that 100% reneable energy is possible. It’ more of an urban myth. The BP statistical review for 2014 just came out. Renewable energy made up a larger percentage of the global energy mix in 2004 than it did last year.

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            • By Forrest on June 13, 2015 at 5:45 am

              Alternative energy enthusiasts will throw out the information that society needs to conserve more and we can live on less. O.k. but that’s normal good conservation ideals that need not be presented, at least upon a solution of power generation. We will utilize more energy upon the future, unless we spiral society to survival life quality per bad leadership. Citizens desire better quality of life, they will forgo waste, but they are not willing to submit to minimalist life per taking the bus and commune living. Energy department is bullish on nuclear power. They still spend money on research to make it better. Fusion power will be a huge energy source, eventually. We need to reprocess spent nuclear waste. SMRs or next gen nuclear expected to be popular. Investors and business already positioning for gold rush of meteor mining for rare metals and nuclear fuel. The H3 moon dust is supposed to be a perfect nuclear fuel. Just yesterday heard a report on robot competition per typical emergency requirements. Fukshima disaster could have been diverted by such robots operating within high radiation zone per valve operation. This makes me think deep sea methane crystal harvest will become economical as well as deep ocean oil well safety.

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            • By Forrest on June 13, 2015 at 6:10 am

              Coal power pollution should be evaluated per specific power plant. As the emission technology improves, modern coal steam power plant is very low polluting except for CO2. The efficiency is low per typical steam turbine as nuclear. China, Russia, India, and the rest of developing economies with low tech coal plants the high polluters. It was a good move to obsolete our old coal plants as new coal is much better, but U.S. coal is not very polluting overall, present day, and not expected to go away. They are expected to continue dominance within power generation, especially internationally. So, we would benefit environment more by inventing cost effective pollution controls and avoid ostridge head in ground mentality per idealism. Coal R&D continues with the fuel cell and promises a high efficient combined cycle system. Also, just plain hydrogen generation and storage for countries energy needs. Nuclear power could be a formidable supplier of hydrogen as well and if what scientist believe, that the future will be a hydrogen economy, both will have a place.

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    • By Russ Finley on June 12, 2015 at 1:49 pm

      …your solar cost example is not typical for most of the USA.

      From the article:

      One problem with solar is that there is no “one size fits all” solution.
      Location, total electricity consumption, how much is used at what times
      of day (home load profile), the orientation, size, and shape of roof,
      are different for just about every house.

      Summarizing your comment: solar can eventually save some people money, depending on circumstances. No argument there, but if one were to assign error bands to the dozens of assumed values for variables used to estimate solar costs over time, the best one can do is estimate the probability of return on investment, assuming you are still alive and at that same residence when/if profitability arrives.

      Nobody can predict the future.

      1) Will the return of a hot stock market make you wish you had not put that money into panels?
      2) Will maintenance costs be higher than estimated?
      3) Will energy costs be lower than estimated (look at natural gas and oil today)?
      4) Will a grid rental fee be added to your bill and how much will it be?
      5) Will you move away, abandoning your investment?

      …and on and on.

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      • By ReaMuch on June 12, 2015 at 3:18 pm

        Summarizing your article. Electricity is already low carbon and inexpensive in the PNW and the Tesla Powerwall is too expensive for me. No argument with that logic.

        1. The stock market is a roller coaster. Everyone eventually cashes out. Will you cash out at the top or bottom of the hill? What if the stays low for 10 years when you need to cash out? See history of market.
        2. Panels and micro-inverters come with warranties. I’m capable enough to install and maintain my own PV system, although the numbers I’ve used above are based on paying someone to install it.
        3. Energy costs will continue to go up over time, likely above the core inflation rate, due to externalities finally being accounted for. Short term reductions in price (current NG and gasoline) doesn’t change the upward trend line.
        4. No grid rental fee here with a Net Metering Contract. If one was added by the utility, it would be breach of contract and we would go to court and we would win.
        5. Yes, we do plan on moving 10-15 years down the road. Our solar system will have recouped it’s initial cost and will be a great asset in selling the house in any housing market. Call that a competitive advantage.
        6. See #4.

        Solar PV worth the effort? Yes, it will displace high carbon coal electricity production plus reduce SOx, NOx, and heavy metal pollution in our area. When we already use 60% less electricity than fellow citizens with the same size home due to our intelligence and efficient behaviors, one could say that either electric rates are already too low or the rate system itself encourages waste (answer- both). We already pay app. 8% per month electric grid access fee, regardless of use.

        Yes, solar PV isn’t appropriate everywhere. I’m glad it will work with our home. If our utility sold low carbon, low pollution electricity for $.16/kWh I would just go with that option.

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        • By Russ Finley on June 12, 2015 at 4:12 pm

          Yes, solar PV isn’t appropriate everywhere. I’m glad it will work with
          our home. If our utility sold low carbon, low pollution electricity for
          $.16/kWh I would just go with that option.

          We don’t seem to disagree on that point. And there are times I wish I lived in a sunny place with coal power so I could justify putting solar on my house! My neighbors with solar on their roofs don’t have a clue that they have gone to great expense to, in theory, increase carbon emissions.

          I expected that you would respond with your predictions to the short list of future assumptions. Now to assign probabilities to each and do a statistical analysis ; ).

          We already pay app. 8% per month electric grid access fee, regardless of use.

          That won’t save you from increased charges. In some places there are already various energy surcharges (which come with different names) that have been applied on top of the grid use fee. It’s a Catch 22 that if you remain connected to the grid, but don’t pay an electric bill, the utility by law, has to stay solvent by increasing fees somehow, either to everyone else, or to those drawing energy from the grid but not paying an electric bill. With panels, you certainly should get a discount because they can’t charge you for their fuel costs, but that is only part of their costs. The energy you draw when the sun isn’t shining is coming from powerplants somewhere that have to be paid for.

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