Wood-Burning Power Plants: Carbon Neutral – Really?

In recent months,  forest biomass (wood burning) power plants have received positive press for their ability to turn waste wood into electic power.  However, there’s an on-going debate in the power/environmental community relative to the carbon footprint of conventional biomass power.  Power plant proponents claim that these plants release no more carbon than a healthy forest ecosystem over time.  Opponents are quick to remind us that this is misleading, in that, forest ecosystems release carbon over many decades, whereas power plants release carbon (as carbon dioxide) in the very near term.

One alternative that has been presented elsewhere here at Cascadia are carbon neutral (or even carbon negative) solutions for power plant projects that employ algal synthesis or “algae farms” to both 1) capture carbon dioxide emissions, and 2) produce oil and feed stocks in return.  If you’re interested in reading more about this process, just click “Algae” in the post cloud on right side of this page.

Back to the question of whether or not these conventional biomass power plants are carbon neutral:  Below is an excerpt from a recent article in Scientific American which details the thinking in regard to these power plants.

Wood-Burning Power Plants–Carbon-Neutral or High Carbon Emitters?

Environmental groups are pressing the EPA to backtrack on its plans to exempt biomass from climate regulations, arguing that such a step would spark an uptick in unregulated carbon emissions

By Dina Fine Maron and ClimateWire | Wednesday, April 6, 2011 | 14

Image: California Energy Commission

Environmental groups yesterday pressed U.S. EPA to backtrack on its plans to exempt biomass from climate regulations for the next three years, arguing that such a step would prompt more fuel switching to biomass and spark an uptick in unregulated carbon emissions.

The Natural Resources Defense Council and Southern Environmental Law Center (SELC) opposed a proposed rule from EPA that would allow facilities burning woody waste, landfills and ethanol facilities to be exempt from carbon regulations for the next three years.

The proposal would “provide incentives to fuel switch” in order to avoid climate regulations, said Navis Bermudez, deputy legislative director for SELC. The exemption would leave these emitters unregulated, and could result in higher greenhouse gas emissions than using coal, she said at a public hearing on the rule, echoing the sentiments of several other environmental organizations that spoke.

At the heart of the matter is a controversy over carbon accounting and the length of time required to replenish carbon reservoirs.

Past federal regulations have accepted the premise that facilities fueled by woody waste are “carbon-neutral” — merely speeding up the carbon cycle that would naturally occur as plants decompose.

But a study commissioned by Massachusetts last year and conducted by the Manomet Center for Conservation Sciences indicated that burning wood for energy generally results in greater emissions of greenhouse gases per unit of energy than using fossil fuel, based on the efficiency of tapping each resource.

The study rested on a number of caveats — including geographic area, how forestlands are managed and if tree refuse or entire trees were utilized, but its results suggested that moving from coal plants to biomass could actually boost Massachusetts’ carbon emissions in the next several decades (ClimateWire, July 12, 2010).

That finding has been a touchstone for environmentalists concerned that the carbon footprint of such plants is not being addressed.

EPA contends that providing a three-year deferral on the issue will allow it to perform scientific analysis considering to what extent — if at all — these emitters should be included in regulations.

Some in industry worry about uncertainty

The agency will examine the science around biogenic carbon dioxide emissions and develop a rulemaking on how these emissions should be accounted for in future permitting requirements, it said in the proposed rule. The agency is accepting comments on the issue through May 5.

Biomass advocates including the National Alliance of Forest Owners (NAFO) and the Biomass Power Association yesterday hailed EPA’s decision to study the matter and reiterated that climate regulations that kicked into effect in January and affect large stationary sources should not apply to them.

Support for biomass as a renewable energy source would be undermined by considering it a carbon polluter, said Dave Tenny, president of NAFO.

Tenny, whose group originally asked EPA for the exemption, argued that it would be impossible to measure how woody waste would be used if it were not used in biomass facilities; thus any calculations could not fully settle questions of carbon accounting.

Meanwhile, Bob Cleaves, president and CEO of the Biomass Power Association, urged the agency to move faster than the proposed three-year timeline on its final decision to exclude biomass — in order to provide market certainty for potential biomass investors, he said. “Delays will cause regulatory uncertainty and economic harm in areas of the nation that continue to suffer from high unemployment and anemic economic growth,” he said in prepared remarks.

The hearing comes on the heels of an announcement last week from Dominion Virginia Power that it expects to convert three of its Virginia coal-fired plants to run on biomass.

Dominion would have moved forward with its fuel-switching plans regardless of whether EPA granted the three-year delay request, Dominion spokesman Jim Norvelle said in an email. The company expects its biomass plants will be online by 2013 if its plans are approved, and said the facilities would help the company meet Virginia’s voluntary renewable portfolio standard.

Richard Wiles, senior strategist at the Partnership for Policy Integrity, a group focused on applying science to public policy issues, blasted the proposed exemptions yesterday, stating that EPA does not need three years to study this matter. “The state of Massachusetts did a fine job of it in nine months,” he said, referring to the Manomet study. “Waiting three years will have serious real world effects,” he said. “As things stand now, every plant built during that time will be a permanent carbon polluter.”

Pacific Biomass Conference – Algae Solution May Be Closer Than We Think

An earlier post discussed the issue of recovering CO2 from forest biomass energy generation by inserting an algal synthesis process to capture CO2.  The recent conference provides a “lay of the land” and specifically mentions forest residues.  Here’s an excerpt of a report from Biomass Digest:

In California, the Pacific West Biomass Conference opened with the bright promise of the State’s enormous biomass resources. However, several speakers in the morning’s plenary sessions invoked major statutory and regulatory barriers to fulfilling this promise. There are conflicting definitions of biomass and what qualifies as a legitimate source or conversion process. The conflicts run across the standards for earning carbon credits and renewable energy credits, attaining the Renewables Portfolio Standard (for utilities), meeting AB32 carbon reduction goals, and meeting California Integrated Waste Management Board landfill diversion goals. These issues reach beyond California since the State’s standards strongly affect those of many other States.

For instance, the California Renewables Portfolio standards do not accept organic municipal solid waste as a source for renewable energy (except for landfill methane capture and gasification of MSW). Green-e, the favored third party certifier for both RECs and carbon credits, denies greenhouse gas reduction credits to energy from solid and liquid biomass from nearly all sources.

Jim Stewart, Chairman of the California Bioenergy Producers Association described Assembly Bill 222, drafted five years ago to rationalize definitions, sources, and technologies. This bill has been approved in the Assembly but the Senate Environmental Committee is sitting on it, in response to strong pressure from environmental organizations. Several speakers emphasized the need to work with the environmentalists to help them understand the relative impacts and benefits of biomass energy compared with fossil energy. (No representative from the enviro organizations were on the agenda.)

Amplifying Feedstocks

Reliable access to biomass feedstocks was a recurring theme. Companies are researching new species, such as Sustainable Oils’ Camilina sativa and Viaspace’s Giant King Grass project in a tropical region of China.  <link to earlier Digest stories> Some companies are focusing on “waste” streams or residues, others on scanning for new strains and enhancing dedicated energy crops through traditional plant breeding or genetic engineering.

One of the most innovative approaches to feedstocks was Dallas Hank’s baseline assessment of idle public lands, such as freeway frontage, railroad and airport land, and military bases. This Utah State University Extension researcher estimates that over twenty million acres of US public land could be farmed for dedicated biomass crops. His economic analysis shows the overall costs of production would be a small fraction of growing bioenergy crops on private land.  (See www.freewaystofuel.org for Hank’s powerpoint and information on the Freeways to Fuel Alliance.)


Maintaining viability of algae companies

In the Biorefinery track algae companies had strong representation. Kent Bioenergy, Aurora Biofuels, Genifuel Corporation and Bioalgene presented their approaches. One manager responded to the question “When do you think your company will be producing cost competitive biodeisel.”  “I hope its within my lifetime,” was his modest response. Others projected three to five years to commercial application.

However, the algae developers emphasized business models based on revenues from sequestering carbon and processing other pollutants, on the input side. On the output side they are seeking to create multiple co-products to achieve ROI as biodiesel production evolves to cost competitive status.

For instance, Kent Bioenergy uses effluent from a waste water treatment plant on the Salton Sea and landfill leachate (SE California) as nutrient rich media for growing microalgae. Bioalgene has a demonstration site in Boardman OR that captures CO2 from a coal fired power plant to speed growth. Genifuel gasifies nuisance wet algae to produce methane, as well as plants like water hyacinth that clog waterways. This site’s coproducts include sterile water and organic fertilizer. <http://www.biofuelsdigest.com/blog2/2009/05/08/genifuel-licenses-new-method-for-converting-algae-to-natural-gas-for-power-gen> Other companies mentioned animal feed, fertilizer, biopolymers, and feedstock to anaerobic digesters as coproducts.

This systems business model of diversifying input and output revenue streams enables these algae companies to remain viable while evolving a commercially competitive biofuel. Cellulosic ethanol producers described similar strategies.

Bryan Yeh of SAIC presented the DARPA sponsored study of algae companies and recommendations for successful algae business development. He says the report will likely not be released for another 6 months.

Biomass Investment

One of the fully subscribed tracks was the late addition — Biomass Power Project Development & Finance. These four sessions offered very informed commentary by investors and a great deal of time for questions and discussion. The investors” case reports demonstrated the active role they play in supporting their companies’ project teams in evolving sustainable business models that mitigate risks for both equity and debt investors.

Learning from one another

Conference participants commented on the great value of cross-pollination between different technologies at an event like this. One company learns from another’s solutions to basic strategic issues of feedstock supply, sustainable business models, integration of technologies, or coproducts. The sharing from presentations was greatly amplified by discussions in the breaks, lunches and late-afternoon receptions. Although BBI tightly scheduled the formal presentations, it was generous in time for breaks, lunch, and late afternoon receptions.

Diversity of the biomass industry cluster

Participants also commented on how the diverse sponsors and exhibitors were a good cross section of the biomass cluster. These included service and product suppliers (law firms, bioengineering companies), manufacturers of equipment for processing feedstocks (grinders, shredders, pellet or briquette compressors), construction engineering firms, the firms harvesting ag and forest residues, and some of the biomass conversion companies. Many firms in the supply chain have expanded from their traditional product lines to embrace bioenergy and biomaterials. In some cases they become project partners rather than vendors.

Forest Biomass, Algae and Oil

Utilizing forest biomass for energy production is in vogue in the Pacific Northwest right now.  Nippon Industries in Port Angeles, WA is moving toward building a 20 megawatt project.  One recurring theme seems to trip-up this sort of energy solution:  CO2 is a primary by-product of the generation process.  While some argue that burning biomass is still carbon neutral since CO2 is released from the biomass over time anyway, it remains an issue if you’re a member of the camp that wants to reduce CO2 emissions NOW.

One possibility to greatly reduce emissions in biomass energy production is algal synthesis.  MBD Energy is currently working on pilots to turn power plant CO2 emissions into oil, feedstock and water.  The development hurdles are enormous but potentially do-able.

Professor Chris Rhodes of the U. K. had these observations about algae:

Nonetheless, there is a consortium (National Algae Association) in the U.S. that is actively seeking a future in which algae are grown on a large scale and converted to oil-alternative fuels. Certainly, it is likely that algae will become an essential component of the mix of means to keep transportation going by means other than crude oil.

The claims of the NAA are undoubtedly true, that ultimately the supply of petroleum must decline, oil prices will continue to be volatile with knife-edge consequences for the world economy, and a wholesale industry based on algae would provide precious and needed jobs and economic development in the U.S. The approach could be introduced on necessary levels for all nations and even a village “pressure cooker” to provide algal fuels for small communities.

More news at 11 . . . . .