A recently-published blog post from Bill Schlesinger of the Cary Institute of Ecosystem Studies labels renewable wood bioenergy a “hoax.” But is this type of rhetoric warranted?
The answer, according to international experts and climate authorities, is no. Schlesinger’s post makes incorrect assumptions about carbon payback time, and fails to distinguish the intermittent power generation of solar and wind from the baseload-generation that wood bioenergy can provide.
Leading experts and international climate science authorities such as the UN’s Intergovernmental Panel on Climate Change (IPCC) agree that wood bioenergy is an effective tool to phase out dirty fossil fuels like coal with a low-carbon alternative. But how, exactly, does wood bioenergy work to reduce GHG emissions in the fight against climate change?
Background: Phasing Out Fossil Fuels Is Critical
As Axios explained earlier this year, decarbonizing the world’s existing power generation capacity – rather than just adding lower-carbon capacity – is essential to global climate change mitigation efforts. The fact is that population growth and global reductions in poverty have increased worldwide demand for energy – and while renewables like wind and solar have increased in scale, they have mostly gone toward meeting this increased demand, leaving the underlying issue of carbon-intensive power generation unresolved.
“Like adding salad to your pasta doesn’t help you lose weight,” Axios writes, “adding cleaner energy to a world run on fossil fuels won’t cut greenhouse gas emissions. Yet that’s what we’re doing now.” This means that unless we directly reduce the use of carbon-heavy fossil fuels like coal, adding in wind and solar energy will make little difference. Wood bioenergy is one of the tools we can implement to directly phase out fossil fuels today.
Wood Bioenergy Complements Wind And Solar
Wood bioenergy produces baseload energy, energy that supports the backbone of the power grid and can be quickly ramped up or down depending on demand. By contrast, today solar and wind are intermittent power sources; they don’t provide baseload energy. In other words, wood bioenergy complements solar and wind by replacing coal, the dirtiest energy source on Earth and currently the baseload source of energy for much of the world. They are not competing energy sources, but rather complementary ones. Moreover, wood bioenergy is one of the easiest ways to achieve lower-carbon baseload energy, since existing coal plants can be quickly retrofitted to run on wood biomass in a cost-effective manner.
Wood Bioenergy Is Renewable And Emissions Are Absorbed By Growing Forest Landscape
In FFJ’s last research highlight, we explained how the markets supported by wood bioenergy protect and grow forests, increasing forests’ ability to absorb carbon dioxide from the atmosphere, as trees naturally absorb carbon through photosynthesis. Wood bioenergy production is a low-carbon energy source because the carbon emitted by burning biomass for electricity generation is simultaneously reabsorbed by the growing forest landscape.
Yes, wood biomass produces some carbon emissions. But on net, it produces significantly fewer emissions than widely-used fossil fuels, which is why organizations like the United Nations have repeatedly confirmed that bioenergy is a necessary component of the global effort to mitigate climate change.
It is also important to note that the integrated forest products economy is both renewable and sustainable. Expert foresters manage forest acreage to produce a consistent volume of wood fiber each year, with outputs going to everything from paper to lumber to bioenergy. By design, this system maintains forest acreage – if forests were depleted faster than they were growing, this consistent volume would dry up. In other words, forests are managed like renewable crops, and in this case, a crop with the added benefit of sequestering atmospheric carbon.
Studies Demonstrate The Carbon Reduction Benefits of Wood Bioenergy
Multiple studies from leading researchers have demonstrated the carbon reduction credentials of wood bioenergy.
Researchers from the University of Illinois, University of Georgia, and North Carolina State University found that the GHG intensity of wood biomass electricity is “74% to 85% lower than that of coal-based electricity.” Researchers from the University of Georgia, University of Illinois, Stockholm Environment Institute, and Universidad Nacional Autónoma de México found in 2014 that wood pellets for electricity generation can reduce GHG emissions in the United Kingdom between 50% and 68% compared to fossil fuels.
Importantly, wood bioenergy leads to rapid GHG benefits, which is critical because the world is facing a limited window in which to action to effectively mitigate climate change. As a report from Utrecht University and the Oak Ridge National Laboratory found in 2017, wood pellets reduce GHG emissions within 0-29 years, with commercial thinnings and harvest residues leading to GHG benefits within several years. This echoes research from the Society of American Foresters, which concluded that the “GHG benefits from using forest residues to produce electricity are generally observed in less than a decade or two.”
In fact, more than 100 leading international scientists have recognized the importance of wood bioenergy, penning a letter noting that, “The long-term benefits of forest biomass energy are well-established in science literature… Forest biomass energy yields significant net decreases in overall carbon accumulation in the atmosphere over time compared to fossil fuels.”
International Climate Authorities Embrace Wood Bioenergy
Leading international organizations and climate science bodies recognize wood bioenergy as a critical low-carbon energy source.
The UK Committee on Climate Change notes that, “Globally, a scale-up in bioenergy production is needed to meet the Paris Agreements goals.” The International Energy Agency agrees, stating that bioenergy can “play a critical role in facilitating transition to low-carbon energy systems.”
This echoes the recommendations of the United Nations IPCC, the top international climate science authority, which recognized last year that all pathways to mitigate climate change include bioenergy, and that sustainable forest management with biomass production can reduce GHG emissions.
Research References:
Environmental Research Letters (2014)
Potential greenhouse gas benefits of transatlantic wood pellet trade
Authors: Puneet Dwivedi (University of Georgia), Madhu Khanna (University of Illinois), Robert Bailis (Stockholm Environment Institute), Adrian Ghilardi (Universidad Nacional Autónoma de México)
Key Finding: Wood pellets for electricity generation can reduce GHG emissions in the United Kingdom between 50% and 68% compared to fossil fuels, and overall, the “use of imported wood pellets for electricity generation could help in reducing the United Kingdom’s GHG emissions.”
Environmental Research Letters (2015)
Carbon savings with transatlantic trade in pellets: accounting for market-driven effects
Authors: Weiwei Wang (University of Illinois), Puneet Dwivedi (University of Georgia), Robert Abt (North Carolina State University) and Madhu Khanna (University of Illinois)
Key Finding: “Across different scenarios of high and low pellet demand that can be met with either forest biomass only or with forest and agricultural biomass, we find that the GHG intensity of pellet based electricity is 74% to 85% lower than that of coal-based electricity.”
Global Change Biology Bioenergy (2017)
Authors: Hanssen et al. (Radboud University Nijmegen, Utrecht University, Oak Ridge National Laboratory)
Key Finding: Wood pellets reduce GHG emissions within 0-29 years, with commercial thinnings and harvest residues leading to GHG benefits within several years.
IEA Bioenergy (2017)
Key Finding: Most IPCC pathways to reducing global GHG emissions “involve a large share of bioenergy. Biomass is a renewable resource with large potential for expansion, and unlike other renewable resources, biomass can be stored and converted to different energy carriers. It can thus play a critical role in facilitating transition to low-carbon energy systems.”
National Association of University Forest Resource Programs (2019)
Science Fundamentals of Forest Biomass Carbon Accounting
Key Finding: “The long-term benefits of forest biomass energy are well-established in science literature,” the letter reads. “Forest biomass energy yields significant net decreases in overall carbon accumulation in the atmosphere over time compared to fossil fuels.”
Renewable Energy Association
Bioenergy in the UK –The state of play
Key Findings:
1: “Bioenergy is recognised as a key renewable energy technology, and an essential component of a low carbon energy economy, internationally and in the UK, playing an important role in providing electricity, heat and transport fuels.
2: In the last 10 years bioenergy’s contribution to the UK has grown strongly, helped by a supportive policy framework. Bioenergy is the largest contributing renewable technology in the UK, providing 7.4% of primary energy supply and: 11% of UK electricity 4% of energy used to produce heat 2% of energy needed in the transport sector.
3: Bioenergy has led to a “4% reduction in UK greenhouse gas emissions.”
Society of American Foresters (2014)
Forest Carbon Accounting Considerations in US Bioenergy Policy
Authors: Reid A. Miner (NCASI), Robert C. Abt (North Carolina State University), Jim L. Bowyer (University of Minnesota), Marilyn A. Buford (USDA Forest Service), Robert W. Malmsheimer (SUNY ESF), Jay O’Laughlin, Elaine E. Oneil, Roger A. Sedjo, and Kenneth E. Skog (US Forest Service)
Key Findings:
1: “As long as land remains in forest, long-term carbon mitigation benefits are derived from sustainably managed working forests that provide an ongoing output of wood and other biomass to produce long-lived products and bio-energy, displacing GHG-intensive alternatives.”
2: “The demand for wood keeps land in forest, provides incentives for expanding forests and improving forest productivity, and supports in-vestments in sustainable forest management that can help offset the forest carbon impacts of increased demand.”
3: “GHG benefits from using forest residues to produce electricity are generally observed in less than a decade or two.”
UK Committee on Climate Change (2020)
Land use: Policies for a Net Zero UK (2020)
Key Findings:
1: “Sustainably managed forests are important for reducing emissions across the economy. They provide a store of carbon in the landscape and harvested wood can be used sustainably for combustion and carbon sequestration in the energy sector…(33)”
2: “In all scenarios for the achievement of net-zero, sustainably harvested biomass can play a significant role, provided it is prioritised for the most valuable end-uses (98).”
3: “Globally, a scale-up in bioenergy production is needed to meet the Paris Agreements goals, and the UK should be at the forefront of developing and demonstrating good governance practices (100).”
United Nations Intergovernmental Panel on Climate Change (2019)
IPCC 2019 Special Report on “Climate Change and Land”
Key Findings:
1: “Sustainable forest management can reduce the extent of forest conversion to non-forest uses. Sustainable forest management aimed at providing timber, fiber, biomass, non-timber resources, and other ecosystem functions and services, can lower GHG emissions and can contribute to adaptation. (high confidence).” (SPM B5.4, page 25)
2: “All assessed modelled pathways that limit warming to 1.5ºC or well below 2°C require land-based mitigation and land-use change, with most including different combinations of reforestation, afforestation, reduced deforestation, and bioenergy.” (SPM B7, page 26)
3: “In the long term, a sustainable forest management strategy aimed at maintaining or increasing forest carbon stocks, while producing an annual sustained yield of timber, fiber, or energy from the forest, will generate the largest sustained mitigation benefit…”. (Ch 4, 4.8.5, page 66)