Is Biomass All It's Cut Up to Be?

- by Howard Brown, October 17, 2014, Summit Daily
[[{"type":"media","view_mode":"media_large","fid":"292","attributes":{"alt":"","class":"media-image","height":"360","style":"width: 333px; height: 250px; margin: 3px 10px; float: left;","width":"480"}}]]One possible reason for sticking to the ill-advised Ophir Mountain and other clear-cutting plans is that the clear-cut trees would go to the biomass power plant in Gypsum. Biomass power is renewable energy. It wouldn’t justify destroying Summit County’s wonderful forests and trails, but biomass is green energy right? Maybe not.
Is biomass power a good renewable energy source that we should promote here in Colorado? To answer this, we need to back up and look at where biomass energy comes from. As with most of our energy sources, it starts with energy from the sun. In photosynthesis, plants use solar energy to convert water and carbon dioxide to carbohydrates. Energy is stored in the carbon-hydrogen bonds. (Geologic pressure over time strips the oxygen from plant material to create hydrocarbon fossil fuels.) When animals metabolize carbohydrates, or when plant or fossil fuel material combusts (burns), that energy is released as oxygen combined with the material, returning to the lower-energy carbon-oxygen and hydrogen-oxygen bonds of carbon dioxide and water.
The problem with fuels such as coal and wood is that they are solids. The combustion process requires direct contact between oxygen molecules and molecules of the fuel. For gaseous fuels such as natural gas, that is very easy, individual oxygen molecules readily mix directly with individual methane molecules. For liquid fuels such as petroleum products, vegetable oil or ethanol, that mixing is more difficult and the resulting combustion less efficient. With solid fuels, however, it is exceedingly difficult for individual oxygen molecules to contact individual fuel molecules, so the combustion process is incomplete and far less efficient.
As a result, much less energy is produced per amount of fuel. This both generates more carbon dioxide and other greenhouse gases per amount of energy generated and makes the fuel far less valuable. With its low value as a fuel, biomass can only be an economic fuel if it is inexpensive and very close to the power plant. Indeed, nearly all [a significant and increasing percentage of biomass facilities transport wood from elsewhere. -Ed.] current commercial biomass power uses waste biomass sources burned right at the generation site (pulping liquid at paper mills, scrap at lumber mills and municipal solid waste at collection centers). Also, the incomplete combustion generates air emissions as well as ash.

Consequently, the future of biomass power lies with developing technologies to gasify or liquefy biomass, so that it can be burned more efficiently. This research closely parallels efforts to develop clean-coal technologies. Other biomass research focuses on developing fast-growing trees or grasses.

Gasification and liquefaction technologies are not here yet. You certainly don’t come to the mountains or the arid West for fast-growing trees. Cutting down natural forests and hauling the wood 60 miles hardly qualifies as using industrial waste materials at their source.

Colorado is blessed with great solar and wind resources. These are our best sources for renewable energy. Here and now, at the expense of losing Summit County’s beautiful forests and trails, is clearly not the place for biomass power.

Howard Brown lives near Silverthorne. While he has extensive environmental policy analysis experience at the federal, state and local levels, he attributes his expertise to observing and asking questions while enjoying Summit County’s beauty.