Notes on Energy Efficiency
I arrived in one piece in Hawaii a few days ago, and have been settling in. It is still hard to believe I am here, and I plan to elaborate a bit on why I am here in the near future.
In the interim – and because I haven’t posted anything new in a few days – I thought I would call attention to a story in the New York Times from a couple of days ago:
You have to be registered to read it (although the Tehran Times has reprinted the first page of the article) but I will paraphrase/excerpt it. The article covers a number of facts and myths around energy efficiency:
COMPUTERS AND ELECTRONICS
1. Screen savers save energy
FICTION — With screen savers, electricity is still pumping to keep your computer and monitor running. In fact, screen savers may even use more energy than a basic blank screen.
2. Your computer stops using energy when in sleep mode
FICTION — Computers still use energy when in sleep mode, but about 70% less.
3. You waste more energy restarting a computer repeatedly than letting it run all day
FICTION — Even though a small surge of energy is required to start up a computer, this amount is less than the energy consumed when a computer runs for long periods of time.
4. No energy is used after you turn appliances and electronics off
FICTION — Many appliances still draw a small amount of electricity when turned off. Solve this by plugging into a power strip that you can turn off.
5. It’s more efficient to keep your refrigerator full than half full
FACT — The larger the mass of cold items in a refrigerator or freezer, the less work is required to maintain the appliance’s chilly temperature. (Of course the more work it then takes to get the appliance to its chilly temperature).
6. Hand-washing dishes is more energy efficient than a dishwasher
FICTION — Dish washing by hand actually consumes more water and energy. People typically leave the hot water running, using up to 14 gallons of water on average. GE Appliances’ Paul Riley says to get the most out of an energy-efficient dishwasher, make sure it is fully loaded with food scraped off the plates.
7. Wash clothing with hot water for a truly effective wash.
FICTION — Heating the water for laundry makes up about 90 percent of the energy used in a conventional top-load washer. Using warm and cold water can be just as effective and can slash your energy use in half or more.
CARS AND FUEL
8. It’s better to fill your gas tank halfway because a full tank adds weight and is therefore less fuel efficient
FACT — The lighter your car, the better the fuel economy.
9. If you live in a warm climate, buy a light-colored car.
FACT — The lighter colors reflect the heat, whereas dark vehicles absorb heat and require more air conditioning to cool down.
AROUND THE HOUSE
10. If you live in a warm climate, paint your house a light color
FICTION — A light-colored roof helps dial back the temperature in a home’s attic by reflecting sunlight, but insulation is the key factor when it comes to energy savings. To really cool down your house, focus on proper insulation and plant foliage to block the sun’s rays.
11. Shut the door and vents in unused rooms
FACT — This works only if you close the doors and vents in multiple rooms.
12. Leave the heating or cooling system on all day. If you shut it down when you’re away, the system needs a surge of energy to reach the desired temperature.
FICTION — Switching the thermostat off when you go to sleep or leave for the day will boost energy savings. It will take more energy to bring your house back to the set temperature, but less energy is used during the down times. You can also realize substantial savings by changing the temperature settings. It is estimated that you will realize a 2 percent savings on your energy bill for every degree you cut back.