Can Biomass Save the Day?

Martin Voelker
CRES Jefferson County Chapter

Ask anyone about “Renewable Energy” and solar and wind will be first on their minds, prompted by images of sleek propeller blades and the blue glint of photovoltaic cells. But if you ask the National Renewable Energy Lab’s (NREL) Dr. Helena Chum, she’ll answer: “Biomass, of course!”

As she reminded her CRES audience in Golden, solar, wind, and hydropower together represent only a rather modest slice of the renewable energy pie, whereas biomass in its many forms makes up the bulk. Expressed in exajoule (EJ) biomass scored 55 EJ of the total of 62 EJ generated by all renewables in 2010.

But, what exactly is biomass and what — besides its size and ubiquity — makes it so important? Simply stated, biomass is defined as plant materials, residues of growing and using food, making feed and fiber products, animal processing and their wastes, and the organic portion of our municipal wastes. What makes it important is because when it is used to produce energy in sustainable ways it has great potential to slow global warming.

Biomass energy essentially is akin to a comparatively carbon-neutral solar battery: Fueled by the sun, plants use photosynthesis to produce carbohydrates from carbon dioxide. It’s a short cycle which takes up carbon from the ground and atmosphere and returns it fairly quickly in similar quantities — rinse and repeat. Fossil fuels, in stark contrast, churn up massive amounts of carbon that had been locked into sediments millions of years ago, releasing them all at once. When they’re gone, they’re gone  and no wonder CO2 levels doubled since the Industrial Revolution!

Consequently, biomass has received much consideration in the IPCC’s reports over the years, where Dr. Chum contributed in its Climate Change Mitigation Working Group. Biomass is by definition renewable, can do power generation, transportation fuels, cooking, heating, and lighting, has a big role in agriculture, forestry and the chemical industry. In fact, more and more fossil feed stocks of any kind are being replaced by processes that use biomass, and that caused the U.N. to chart a goal to double biomass by 2030 with its “Sustainable Energy for All” program.

That goal is ambitious because speed is of the essence: the window for action on climate change is closing fast. We have already spent 65% of our global carbon budget that may permit us to stay below a bearable 2 degree Celsius temperature increase.

To call our global carbon situation “complex” would be an understatement. An Integrated Systems approach requires first and foremost sufficient data which means monitoring many factors worldwide, from agriculture, forestry and other land use to economic and industrial activity, all of which are changing rapidly all the time.

Data is needed (and not always available) to estimate emissions as a basis for assessing development strategies that are both low carbon and yet serve to substantially raise the standard of living of the world’s poor.

If that seems daunting, Dr. Chum reminds us that there is reason for optimism: how we do energy, irrigation, agriculture, construction… you name it… currently has huge inefficiencies that can be eliminated, partially as low hanging fruit and partially with research driven advances turned into new best practices.

Take farming, for example, where water, fertilizer, and pesticides are uniformly applied to huge tracts of land, whether they need that much or not. A smarter, data driven approach would be to use site-specific information to adjust all of these appropriately. Similar concepts call for optimizing land use for environmental and economic benefits by assessing its growing potential with multiple metrics.

Another general approach is to couple lands that are not (or no longer) suitable for agriculture and put them into energy production, mostly with perennial plants like switchgrass and short rotation trees. Such efforts have already outgrown the lab and are being implemented on in larger scale.

And while controversial, the role of genetically modified plants is another big factor in the fate of our world. The holy grail here is to turn the comparatively inefficient C3 photosynthesis mechanism of our major food crops into C4 to speed up CO2 conversion to carbohydrates, meaning dramatically higher crop yields on the same land area.

Further, promise comes from biochar: methods where plants or plant waste are pyrolized to yield transportation fuels. The other product is charcoal which gets worked into poor soils. Biochar, done with the right C4 feedstocks, can actually be a carbon negative process, taking more carbon out of the atmosphere as it burns.

To mitigate climate catastrophes on a global scale a wide portfolio of solutions is of the essence. Citing recent assessments from mitigation research Helena Chum assures us that we can indeed roll out Renewable Energy in all its forms —spearheaded by biomass — to increase energy access and well being for the world’s poor. What’s encouraging is the astounding speed of the renewable energy revolution, with every decade bringing massive technological progress.

However, while climate and renewable energy policies can in theory be designed in a compatible way, there are major hurdles, including cost, political and ideological barriers, behavioral and cultural patterns that are hard to change and of course the law of unintended consequences that always raises its ugly head when humanity is dealing with so many unknown unknowns.

Obviously, there are no guarantees for success but with so much scientific talent like Helena Chum, her team at NREL and their connections to research and policy institutions worldwide one has reason to be optimistic.