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By Robert Rapier on Oct 21, 2009 with no responses

Don’t Weep for the Trees

While I have no intention of changing the general theme of this blog, I will spend some essays in the future providing more details behind my new job in Hawaii. I did this on occasion with my previous job at Accsys, but the focus of the blog remained on energy, sustainability, and the environment.

As explained in the previous essay, my new role involves development of an integrated bioenergy platform. We believe this to be a different way of looking at the problem of turning biomass into energy, and then ultimately supplying that energy to customers. We are not tying ourselves to a specific technology platform; we are using different platforms as suited for specific local needs. We are also as concerned about the sustainability of the biomass as we are the sustainability of the processes we will utilize.

Since moving to Hawaii, I have been asked to give talks at the local high school here about energy and sustainability. During one recent talk I was explaining some of the things we are thinking about as a company, specifically for alternative energy in Hawaii. One of the students said “I heard you were going to cut down all the trees.” At that moment, I realized that her view of forestry was much the same as my own view of forestry growing up in Weyerhaeuser country in Oklahoma. I viewed foresters as people who cut down trees, and I associated them with clear cutting.

My views have changed a lot since then, because I have met a lot of foresters and have a better understanding of what they do. Foresters are people who manage forests. With a managed forest, sometimes that means you harvest the trees like you would harvest any other crop. But managing a forest entails replacing what you cut down (thinning is an important exception).

That makes sense when you think about why people went into forestry in the first place: They love trees (and not in the same way that a polar bear loves humans) and they love the outdoors. They are very conscious of the important role trees play in the environment, and as such they are generally very good stewards of the trees and land they manage.

As indicated in my recent interview with Katie Fehrenbacher, sustainable forestry is a critical component of our platform. We have a forestry company called Forest Solutions, and our ultimate goal is to manage all of the forest assets that we will use in our platform.

So why do we like woody biomass? Why not switchgrass? Sugarcane? Crop residues? Various sources of biomass have their strengths and weaknesses. Very high on the list for a sustainable model is to take care of the soil. One of the questions I sometimes pose is “What would the soil condition be after 500 years in a particular service?” If the answer is not approximately as good or better than the present, then it doesn’t meet the sort of criteria that I am looking for (of course taking into consideration that the soil doesn’t have to be utilized for the same purpose for the entire duration).

There are many potential pitfalls when considering biomass. Some sources are heavy users of nutrients, and as such the fertilization requirements can be high – especially when they are on short rotation. This can imply high fossil fuel inputs and a high risk for soil depletion. Some crops are heavy users of water. Sugarcane ethanol has been judged to be potentially sustainable for Brazil, but it may be a different story in areas that require irrigation.

Trees are different. During the first 10 years or so of their lives, trees can accumulate biomass at the rate of 7-10 bone dry tons per acre per year. You may see some switchgrass yields that are claimed to be that high, but those were almost certainly with fertilizer and plenty of water. But even if the yields were the same, the difference is that you have many harvests of the switchgrass over 10 years to get the same yield as one harvest of trees. Each harvest comes at the cost of energy and labor inputs.

But there is an even more compelling reason to utilize trees. Unlike most of the short-rotation crops that are frequently discussed as feedstock for fuel production, trees can actually improve the quality and health of the soil.

While this is not news to our foresters, it was something that I had not given much thought to until recently. I was taking a tour of a new energy lab being built here on the Big Island, and someone pointed out a plot of land behind the lab and said “We tested the fertility of that soil, and it is much higher than that of the surrounding soil.” I asked why, and was told that there used to be a stand of trees there.

What happens is that trees can bring up nutrients from the subsoil and concentrate them in the leaves and bark. This ends up falling back to the soil and adding to the organic material in the soil. Depending on the specific trees you use, managed forests can provide fuel while improving soil quality. You could also envision rotating trees with other crops to rebuild fertility.

A good example of the potential of trees can be found on the Hamakua Coast of Hawaii. For years the coast was planted in sugarcane. While the area gets plenty of water, it is also very hilly. The sugarcane operations led to a large amount of soil erosion. People who were around during that time said that the normally blue water would be brown for long stretches as soil ran off into the ocean.

The sugarcane industry was ultimately abandoned there, and the area is now planted in trees. The erosion has stopped, and the soil has started to recover. The ocean is once again blue there, and I was told today that a reef that had been damaged by soil runoff is healthy again.

So do not weep for the trees we will use. The right trees are ideal sources of biomass if they are properly managed. Besides providing fuel, they are going to perform an important function – recycling nutrients from the subsoil to the topsoil. The trees that are cut will be replanted. The forests we use will be from managed plantations, and not from rain forest or old growth forests.

That is a general overview of the first leg of the platform. There are a number of assets under management, as well as various acquisitions in progress. At some point I will provide details of these holdings and how we plan to use them.