Recommendations to solve California’s biomass challenge

With its world-leading policies on electrification and clean power, California has made important progress towards achieving its climate goals. However, not all emissions are from the energy and industrial sectors. Land-based emissions, including from burning or decaying biomass, must also be addressed to achieve a carbon neutrality goal. Owing to its vast natural and working lands, California produces an enormous amount of these residues annually. A strategy to collect and convert these residues into products can not only avoid this source of carbon pollution but also drive rural economic development, technological innovation and further emissions reductions by replacing fossil fuels.

The Governor’s recent commitment to develop a plan to manage ‘woody’ sources of organic waste (by far the largest source) from forests and agriculture is an important step towards addressing this problem. In a previous post, we shared background regarding a draft of this plan. In this blog, we identify potential priority approaches for biomass utilization, including for durable wood products, advanced biofuels and biomass electricity, that can help California meet its climate goals.

A new vision for biomass

Biomass is a polarizing climate topic – for good reason. The land-use, water and wildlife implications of growing biomass for energy as well as air quality implications from large-scale combustion have had devastating impacts in the United States and around the world.

That said, not all biomass is created equal. In the case of California, its biomass supply is a waste product resulting from other actions including wildfire prevention and agriculture. If this biomass is not managed, it is typically either pile burned or left to decay, releasing carbon and criteria pollutants.

The central question in California, then, is how best to utilize this biomass supply. As mentioned, traditional uses including combustion to generate electricity have proven harmful to air quality and are costly to ratepayers. Meanwhile, there has been significant research and innovation to advance alternative uses of biomass that are cleaner, more scalable, and more useful for supporting carbon neutrality ambitions.

In the Figure below, we highlight an optimal use case for California’s biomass over time. A key priority should be to, where possible, mobilize available biomass into durable wood products such as mass timber. Biomass to fuels such as low-carbon hydrogen and sustainable aviation fuel is also a priority pathway that has a high potential to scale in support of the state’s forest treatment goals as well as deliver other climate priorities, including carbon removal. Finally, biomass electricity is the lowest priority option, and while it can serve a targeted function in some areas a strategy to manage and phase-down combustion is necessary.

Two main product options

Durable wood products including oriented strand board (OSB) or mass timber options such as cross-laminated timber (CLT) are low-carbon product options that the state should seek to maximize where possible. OSB can make use of wood chips, which is a large source of the biomass waste. CLT typically needs medium/log-sized sources of biomass, so is unlikely to be appropriate in all settings. Maintaining support for existing R&D and early business development grant programs as well as developing new policies that incentivize low-carbon building materials are the main policy needs.

Advanced biofuels produced via non-combustion methods such as gasification and pyrolysis is a key product option that is widely shown as necessary to deliver a carbon neutrality goal, including in the 2022 Scoping Plan. There are two reasons for this. First, is that biomass is needed to produce non-fossil, clean fuels to decarbonize aviation, shipping and certain industrial sources. Second, is that biomass can provide carbon removal to compensate for any residual emissions that are likely to remain in 2045. Developing an incentive pathway under the Low Carbon Fuel Standard as well as enabling long-term offtakes from primarily U.S. Forest Service but also aggregated private lands are the main policy needs.

It should be noted that these two product options are consistent with federal priorities on end-uses of biomass. In May 2023, the Department of Energy released a Clean Fuels and Products Shot initiative that identified these priorities. Other relevant DOE initiatives include Hydrogen and Carbon Removal.

Future of biomass electricity

Biomass electricity is currently the only real utilization option for biomass waste. It is also a far better option than pile burning. However, it is in general uneconomic and can be polluting. CARB’s Scoping Plan resolution states, “expansion of biomass combustion for energy production should not be pursued and opportunities for non-combustion solutions should be prioritized”. That said, there should be a strategy to clean-up and improve the efficiency of existing facilities to address immediate needs, such as the processing of high-hazard residues to improve public safety, before transitioning these facilities to preferred technologies (e.g., by prioritizing a redevelopment of these energy sites with gasification technologies).

The state may consider ongoing support for small-scale biomass electricity and/or microgrids as a way to provide reliable power and community resilience in remote areas. However, these megawatt (MW) amounts are expected to provide a very minor contribution to California’s broader clean firm power goals.


Biomass is an important albeit challenging climate issue. It is clear that the majority of California’s emissions reductions will come through electrification. However, land-based emissions from biomass are also a major source of both carbon and air pollution. Additionally, the environmental risk of neglecting excess biomass, which could contribute to increases in catastrophic wildfire, is significant. A strategy that recognizes the latest research and prioritizes the cleanest, highest-value product options is essential. In this regard, durable wood products and (carbon-negative) advanced biofuels are the priority options.

We hope this perspective is useful for stakeholders. For more information, please contact Sam Uden (

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