Biomass burning is not carbon-neutral



    When we turn on the lights, TV or stereo, we rarely pause to wonder where the electricity comes from. Back in the day, all that concerned us in budgeting was whether income exceeded expense. If it did, we were happy. But when we understand the threat posed by global warming and its consequences (floods, drought, heat waves, dwindling snowpack, wildfires), we realize the need to consider more than just money. We now have to ask ourselves about the source of our energy, and the impact of its generation on greenhouse gas emissions.

    Though Oregon has more hydropower than most states, for many of us, the source of our electricity still involves coal or natural gas-fired power plants. Now that Oregon has agreed to turn from coal towards renewable energy, we must ask which energy sources are genuinely clean and thus result in reduced greenhouse gas emissions.

    Our state's last coal-fired power plant in Boardman, operated by PGE, is slated to close in 2020. PGE is exploring the use of wood and energy crops, also known as biomass, instead of coal. If successful, the utility will consider a full transition to biomass feedstock, which would make the Boardman facility the largest biomass project in the country. While the idea of using a renewable resource such as wood to generate power seems attractive, wood is not a clean energy source.

    The first problem with wood as a resource is that burning it produces considerably more carbon dioxide per megawatt hour generated than burning coal. This is because wood is not an energy-efficient resource.

    The pro-biomass argument is that burning trees only releases into the atmosphere the carbon that those trees trapped while growing; burning trees doesn’t release carbon dioxide molecules trapped by plants growing hundreds of millions of years ago, as is the case with fossil fuels. Unfortunately, this argument fails to recognize that, unlike coal, oil and natural gas, living trees continue to remove carbon dioxide from our atmosphere as they grow, countering global warming and climate change. Harvesting standing trees negates their capacity to continue trapping carbon and reducing its atmospheric concentration. Additionally, the rate at which we are currently emitting greenhouse gases is such that we have at most a couple of decades to completely eliminate energy sources that emit greenhouse gases, and replacement trees take much longer than that to recover the carbon released from tree combustion.

    Paradoxically, efforts are now underway federally to label biomass burning “carbon neutral.” The result of this designation is that combustion of biomass would illogically be identified as equivalent to using genuine clean energy sources: wind, solar and geothermal. This could stimulate massive deforestation in the name of fighting climate change - an insane proposition.

    An additional consideration in the biomass equation is the social cost of carbon emissions. This measures the economic cost suffered by humanity as a result of adding carbon dioxide to the atmosphere. The EPA calculated this rate at the low figure of $36 per metric ton of carbon dioxide, rising to $69 by 2050, while further studies suggest this cost is substantially higher. Allowing for runaway warming and crossing tipping points, the figure has been corrected to $700 a ton or more. Regrettably, nowhere in the proposal to define biomass as carbon neutral is the cost of these emissions accounted. A 2016 study of timber sale accounting in western Oregon reveals timber sales generating $6,400 per logged acre, while the social cost of carbon emissions, using the $700 estimate, clocks in at $370,000 per logged acre – a huge net loss per acre. Are our trees more valuable as standing, growing, carbon absorbers, as wildlife habitat, as recreation locations, as timber, or as feedstock for power plants?

    Finally, there’s the Paris Agreement on greenhouse gas emissions. This seeks to curb global warming to 2 degrees C above pre-industrial conditions, with a preferred goal of a 1.5-degree C increase. Unfortunately, we know that the goal of 1.5 degrees is inevitable simply on the strength of greenhouse gases emitted so far. If we are serious about addressing global warming, no energy source emitting greenhouse gases should be awarded a free pass.

    It is simply untrue that biomass burning is carbon neutral; we should not accept this distortion of science. Life on our planet cannot afford continued Greenhouse Gas emissions. Genuinely clean energies such as solar, wind and geothermal are the way forward.

    — Alan R.P Journet, Ph.D., of Jacksonville, is co-facilitator of Southern Oregon Climate Action Now.

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