BIOMASS: A KEY SOURCE OF RENEWABLE ENERGY
Renewable biomass energy produced from wood, the dominant biomass resource in Washington, is made from slash leftover from sustainable timber harvesting operations.
Learn more: Wood is the most natural resource.
For more than a century, forest product companies have created energy from wood to power sawmills and pulp and paper mills. Now, this “old technology” is being modernized and adapted on a broader scale for more efficient use of wood waste to provide renewable energy for communities in the Pacific Northwest and across the country.
Biomass already provides a significant share of energy production in the U.S.:
- Biomass is the country’s largest source of domestic renewable energy, supplying about three times as much energy as wind and solar power combined.
- The more than 100 biomass plants in the country generate 8,500 megawatts of electricity, enough to power 8.5 million homes.
- Provides 18,000 jobs, many of them in rural communities.
- Generates $1 billion a year for the nation’s economy.
- Removes 68.8 million tons of forest debris a year.
- Diverts 36.2 million tons of urban wood waste from landfills a year.
- Each biomass plant contributes $8 million to $14 million a year to the local community where it operates, through salaries, purchases and tax revenue. See Office of Energy Efficiency and Renewable Energy for more information.
In the Northwest, biomass electricity is primarily created by the controlled burning of wood waste that otherwise would be dumped in landfills, burned in open air or left to decompose. Most often the wood waste is burned to heat water and create steam, which flows through a turbine to produce electricity.
Generating electricity with biomass provides environmental benefits that make it a preferred alternative to fossil fuels.
Burning fossil fuels such as coal and petroleum adds carbon to the atmosphere that would otherwise remain trapped underground for perpetuity, absent geologic events such as volcanic eruptions or oil seepage.
In contrast, burning biomass releases carbon dioxide that would have been released anyway through decay or wildfire, and is therefore part of the natural carbon cycle. The carbon dioxide released when the wood waste is burned is replaced when forests are replanted and is reabsorbed by growing plants and trees, so there is no net atmospheric carbon dioxide as long as the carbon cycle is in balance. Thus energy produced from biomass is carbon neutral as long as the region practices sustainable forestry.
The biomass carbon cycle fundamentally differentiates biomass from fossil fuel
If we substitute biomass fuels for fossil fuels, we recycle carbon to the atmosphere rather than introducing geologic carbon to the atmosphere – helping reduce the buildup of CO₂.
The global carbon cycle
These numbers represent the flux of carbon dioxide in gigatonnes.
Sustainable Forestry: Responsible Harvesting and Replanting
Washington State law requires replanting of the forest after harvest. Our sustainable forest management creates new fiber supplies to meet future needs and also ensures attention to environmental and biodiversity objectives for the long-term health of the ecosystems in which we operate. On average, three seedlings are planted for each tree harvested. As a result, the carbon storing cycle is continuously renewed.
Washington State law requires replanting within 3 years. On average, Washington forest landowners replant within 18 months, three trees for every one harvested.Sustainably managed forests that are periodically harvested, planted and regrown to produce a continuing series of products and energy fuel actually sequester and offset more cumulative carbon than forests that are left unharvested.
Trend in Growing Stock in U.S. Timber Lands, 1953-2007
In the United States, we are growing more trees than we are harvesting. Image source: USDA Forest Service, U.S. Forests Resource Facts and Historical Trends, September 2009.
In Washington State, woody biomass is a by-product of the normal forest management harvesting and replanting cycle. Instead of burning piles of forest residue after timber harvests, this underutilized material can be used to produce renewable energy. Forest thinning to improve forest health by reducing fuel loads on eastside dry land forests can provide woody biomass for additional renewable energy feedstocks. Forest thinnings have been identified as the nation’s largest underutilized source of woody biomass.
Forest thinnings have been identified as the nation’s largest underutilized source of woody biomass.
Higher, better use of wood.
Improved milling efficiency has resulted in production of more lumber and less waste.Foresters are dedicated to gaining the most value for the forest products that they sell. Improvements in technology, science and a skilled workforce have improved milling efficiency, resulting in production of more lumber and less waste. When a tree is harvested, all parts of the tree are used. The lumber is used in carbon-storing building materials and wood products. Pulp and paper are processed from wood chips. Energy is produced from sawmill and harvesting residue in the form of biomass. More than 5,000 different products including resins, glues, cosmetics and food are produced from trees.
Our state has more than a century of experience in improving sustainable forestry practices. We are blessed with abundant wood resources that provide more than 2/3 of all potentially available biomass, including forest residue from timber harvests and forest thinning that improves forest health by reducing fuel loads on eastside dry land forests.
Public policy supports the use of biomass for energy production as reflected in the state’s Renewable Portfolio Standards. In 2006, Washington voters approved Initiative 937 requiring electric utilities to produce at least 15% of their energy using renewable sources such as wind, solar and biomass by 2020. Among these alternatives, biomass stands alone as the only one that can provide sustained power, rather than intermittent electricity from wind or solar that is susceptible to shutting down if optimum conditions don’t exist.
In 2008, the Washington State Legislature adopted new laws creating a schedule for reducing greenhouse gas emissions and increasing clean energy sector jobs. The new statutes specifically recognize that emissions of carbon dioxide from combustion of biomass from fuel wood, waste wood or forestry residuals are not considered a greenhouse gas, as long as the region maintains or increases its ability to sequester carbon dioxide through sustainable forestry.
Biomass energy generation also provides significant economic benefits, including tens of thousands of jobs, many of them in rural communities, and it reduces our reliance on fossil fuel imports from other countries, which can improve our balance of trade and enhance our national security.
Biomass energy also provides another way to sustain the economic viability of maintaining working forests on the landscape. Today, many of our private forests lands are at risk due to economic factors that provide a higher financial return for developing land rather than keeping it as forest. Increasing the value of the business of forest management by developing new markets such as bio-energy can provide landowners an additional economic return that encourages continued investment in working forests.
As U.S. Agriculture Secretary Tom Vilsack said, “For forest ownership and stewardship to remain viable, it must remain economically rewarding as well for landowners. By generating rural wealth, we can make it possible again for landowners to sustain our forests and our working landscapes.”
Critics of biomass energy generation have generally either misunderstood the science or relied on distortion to demonize it and downplay its benefits. A recent example was the mischaracterization of a study in Massachusetts that some media reported as casting a negative light on biomass energy generation. In response, the study authors issued a clarification noting the mischaracterization and citing the overall benefits of biomass energy.
It is clear that the growing utilization of biomass to generate energy simply adds to the many benefits that are derived from the sustainable use and management of our forests.
The leading international authority on climate change, the Intergovernmental Panel on Climate Change (IPCC), recognizes the significant potential of forests in mitigating climate change. In its fourth Assessment Report, the IPCC states, “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.”