See also:

• Release of Public Comments on Draft Strategic Plan.  Announcement (dtd 21 Dec 2005) from the U.S. Climate Change Technology Program.  Also available in PDF format.
• List of Commenters.  Also available in PDF format.
• List of Supplemental documents.  Also available in PDF format.
• Strategic Plan, Draft for Public Comment.  Review draft (dated September 2005).

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Goals for GEN IV are very vague. How much is safety to be improved? How much is proliferation resistance to be improved? How much is cost to be reduced?

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No mention is given to a large scale global nuclear system. There is no mention of breeders or extracting low grade U and Th resources, etc.

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The Fusion Energy section uses a great deal of technical language. It might be clarifying to base this section on the Fusion Energy Sciences Advisory Committee's 2003 "Plan for the Development of Fusion Energy," which would provide a clear and consistent framework of explanation, and allow some of the specific technical references to be eliminated.

Lines 10-13: The last paragraph of Section 5.5 clearly belongs in Section 5.6.

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No mention is made of the need for a 14 Mev neutron materials research facility. How else can the fusion reactor materials be designed and tested?

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Where is the notion of a fusion-fission hybrid discussed? The concept could be evaluated in ITER experiments.

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Suggest adding the following sentence at the beginning of the paragraph to explain the concept of inertial fusion:

A very different approach is through inertial fusion, in which an array of intense x-rays, lasers, or heavy ion beams are used to compress and heat a pellet to fusion conditions.

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The inertial fusion energy programs based on lasers and Z-pinches are funded by NNSA, and are following an integrated path in which the needed science and technologies are developed simultaneously and in concert.

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Over $100M has been invested in the Z and laser-based inertial-fusion-energy programs in NNSA. . There has consequently already been significant progress in the S&T, and significant additional advances can be reasonably expected. We believe that the current statement in the Draft Strategic Plan that: "any additional investment in the inertial fusion energy approach awaits successful demonstration of ignition and gain in the NIF" does not account for this progress, and is at variance with the concept of a coherent integrated approach to fusion energy.

We suggest replacing this sentence with: There have been significant advances in key inertial fusion energy technologies including: high-repetition drivers, target fabrication and reactor chamber concepts. Successful ignition and gain on the NIF could stimulate an intensified investment in this approach to fusion energy.

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The potential role of technology in terrestrial carbon sequestration is presented in a balanced fashion. The theoretical or technical potential is clearly indicated as different from what is likely to be achieved based on effectiveness, permanence, competing uses for land, expense, and social willingness. It would be good if this standard were applied to the geological and ocean sections of this Chapter.

Nevertheless, additional context would enhance the potential section. In particular, the notion of full carbon accounting should be introduced. This is different from accounting for all GHGs as is mentioned in various bullets in section 6.3.2. Accounting for the amount of CO2 released or kept from being released while performing carbon sequestration technologies is also required. For example, no-till crop management may result in additional reductions in CO2 released because no-till requires a smaller number of less energy intensive tillage operations than does conventional tillage. Another example where full carbon accounting may be important is fertilizer applications that increase the amount of soil C. The CO2 released during the production of the fertilizer production could be greater than the additional CO2 fixed in the soil.

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6.6 References

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In summary the ocean is currently playing an important role in mitigating significant amounts of anthropogenic CO2 via passive air-to-sea transfer. This natural CO2 uptake, however, is obviously not keeping pace with anthropogenic emissions, and the chemical impact accompanying this flux will have undesirable environmental consequences if allowed to continue. Any scheme that introduces additional molecular, uncombined CO2 to the ocean will contribute to this problem. As reviewed above there are alternative, potentially promising ways for ocean carbon addition that lessen or avoid these impacts. However, all of these approaches have unresolved issues of their own, and the true economic and environmental cost/benefit of all of these schemes is in need of further research. Given the magnitude and urgency of the global CO2 problem, and given the likely inadequacy of any single approach to mitigating this problem, all options for safely using the ocean’s vast potential for carbon uptake and storage need to be seriously and carefully considered.

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Chapter 6 on Capturing and Sequestering Carbon Dioxide does not mention the possibility of direct extraction of CO2 from the atmosphere except by plants. It might be done more efficiently by inorganic chemical absorption. This extraction might be combined with solar bio or photo reduction water to produce hydrogen to react with CO2 to produce fuels in a closed cycle, what Bob Williams calls artificial photosynthesis.

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The draft does not reference the IPCC Special Report on Carbon Dioxide Capture and Storage. The report was approved in September, 2005, and its information should be included in the next draft of the CCTP Strategic Plan. It is a more up-to-date reference than those cited in the draft.

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The chapter fails to include the very significant work in the field, which was completed in November of 2004 and referred to in Section 1407 of the Energy Policy Act of 2005. Carbon Dioxide from the combustion of coal has been captured as part of Proof of concept testing performed by the USDOE/NETL and Jupiter Oxygen under a CRADA agreement, with important results and advantages. Please see the link to the press release on the results. (http://www.jupiteroxygen.com/
spotlight/news.php?id=6).

The core of any effort to optimally mitigate Carbon Dioxide must be the point source. It has been shown that boilers can greatly reduce their potential emissions by using oxyfuel combustion systems. When optimally done with undiluted high flame temperature, the increased thermal efficiency results in significantly less fuel being used. Moreover, optimal oxyfuel combustion acts as an enabling technology for the Integrated Pollutant Removal technology, and this combination of technologies has shown the practical ability to remove or capture virtually all pollutants including CO2.

This work must be included in Strategic Plan, especially since it shows how coordination between industry and the USDOE/NETL can demonstrate the best results in pollution abatement for sustainable energy. The work is important and needs to be included.

Under specific comments, we have included several corrections that fall into two areas.

3) Application - Oxyfuel combustion has been in every day use for nearly a decade. The corrections will aid in the potential readers understanding as to how oxy-fuel combustion is actually used as well as how it is best used.

4) Update - Corrections made to bring current work into focus; not repeating work that was completed years ago.

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Carbon Capture Future Research Directions

The great majority of the more than 300 GW of existing US coal fired generation is provided through combustion of coal, in conventional pulverized coal and cyclone boilers. Retrofitting oxy-combustion modifications to a portion of these plants would provide a means to produce concentrated streams of carbon dioxide. This would enable sequestration, to affect substantial reductions in total greenhouse gas emissions to the atmosphere from the existing fleet of power plants. Additionally, there are plans to build new pulverized coal plants; and some of these plants should be candidates for oxy-combustion systems. Similar comments apply for generation outside the US.

Overall system optimization opportunities include integration of facilities for oxygen supply, coal combustion, power generation, compression of carbon dioxide, etc. Reductions in overall system costs can thus be anticipated with integration of cryogenic oxygen supply with the entire power generation complex.

Ocean Sequestration Future Research Directions

The reaction of combustion-generated flue gas from fossil-fired power plants with limestone and seawater is an innovative research opportunity. The creation of bicarbonate provides an avenue to indirect injection that should have minimal impact on the ocean environment.

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"growth in atmospheric CO2 concentrations. Currently the main focus areas for research and development"

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share), even under high carbon management requirements. In summing up the imperative for CO2 capture and storage as part of future use of fossil fuels, Lord Oxburgh, Chairman of Shell Oil stated, "[CO2] sequestration is difficult, but if we don't have sequestration then I see very little hope for the world." (The Guardian, June 17, 2004).

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other types of geologic storage and terrestrial sequestration options, as well as consideration of ocean carbon storage.

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anthropogenic CO2, and is playing a critical in lessening the impact of current anthropogenic CO2 emissions by passively absorbing some 7.3 Gt of excess atmospheric CO2 per yr (Sabine et al., 2004). The potential storage capacity of the ocean is largely unknown, although some

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Sentence beginning Larger

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Promising technologies have been identified and targeted for large scale development in the next several years. This would include the high temperature oxy-fuel technology as identified under Section 1407 of the Energy Policy Act of 2005.

Reason re-write: update to recent news that authorizing language for oxyfuel is funded.

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Comment 1: to an attachment offered on page 3 line 32

3.0 CAPTURING AND SEQUESTERING CARBON DIOXIDE

3.1 GEOLOGICAL SEQUESTRATION

3.1.1 CO2 CAPTURE AND SEPARATION

1) Graphic at top of page does not reflect an accurate description of CO2 capture, the provided document does.

Picture here [see other attachment]

2) Under System Concepts, the definition of Oxy-fuel combustion should be rewritten as the technology has been applied in industry for nearly a decade and as the technology has been tested for power plants with the best results under DOE CRADA programs. The description is both misleading an inaccurate. Please change.

2nd bullet point

Oxy-fuel combustion. Pure oxygen rather than air charged to the combustion chamber, producing greater radiant heat transfer and reduced flue gas volume consisting of CO2 and water. A portion of the CO2 is recycled to propel the fuel (for example coal) without air, and to balance the heat transfer between the radiative and convective sections of the boiler. The resultant high temperature flame, of the patented process, increases efficiency because the flame is not diluted and heat loss is minimized due to the exclusion of nitrogen from the air thereby creating significant fuel and other savings. While the lower flue gas volumes (because there is no nitrogen from the air) enables other pollution control technologies (like Integrated Pollutant Removal or even mercury control alone) to be significantly less costly and more highly efficient.

Under Technology Status/Applications

Oxy-fuel combustion systems have been used on Industrial boilers using both coal and natural gas. Trials, by Jupiter Oxygen working under a USDOE/NETL CRADA, have shown that boiler material changes are not required. Integration of Oxy-fuel combustion and Integrated Pollutant Removal was successfully operated under a separate CRADA agreement between the Albany Research Center and Jupiter Oxygen using coal as the fossil fuel. 95% of the CO2 was captured while removing more the 99% of the SOX, 99% of the PM including 80% of the PM 2.5. NOX results post combustion before other control, were recorded at .088 lbs/MMBtu (.05 lbs./MMBtu is expected). The tests also showed that up to 90% of the mercury was captured, making 90% mercury capture practical. Cost estimates for the combined process system are on the order of 5.1 cents (U.S.A.)/kWh with amortized capital expenses, including a production cost of 1.7 cents (U.S.A.)/kWh (costs which are lower that those for alternative technologies to achieve the same results).

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High temperature oxygen fired combustion has completed proof of concept testing under a patented process and DOE CRADA projects. CO2 from the combustion process was recovered at rates of up to 95% using coal as the fossil fuel. In oxygen fired combustion, oxygen, instead of air, is used in combustion of petroleum coke, coal or biomass fuels. Recycled flue gas has been identified to balance heat transfer between the radiative and convective sections of existing boilers, but should not be used to dilute the flame temperature which would decrease thermal efficiency. This technology is applicable to the economical retrofit of the large existing fleet of power generating equipment using existing materials while decreasing the use of chemicals for pollution removal. Furthermore modification to high temperature oxy-fuel combustion will result in fuel savings and reduced cost for capture or removal of all pollutants. Future power plant may require greatly reduced flue gas recycle rates which will add flexibility to design allowing for a reduction in boiler size and costs in the range of 60%.

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Section 6.1: Carbon Capture, Page 6-4, lines 3-8 & Page 6-5, lines 42-45

Oxygen-fired combustion research and demonstration is important as stated in the above sections in order to determine the ease of CO2 capture from the combustion process. R&D investment in oxygen transport membranes is a good step in providing effective and low-cost separation technologies. However, in addition to the focus on new plants, steps should be taken to evaluate technologies to retrofit the numerous existing power plants and other large CO2 point emitters. A great example would be a 2-step retrofit of existing PC plants. (1) Convert to supercritical PC for efficiency comparable to new IGCC; the conversion is close to economically justifiable due to the efficiency gains (2) Use oxyfuel for easier carbon capture from supercritical PC plants when sequestration is viable.

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"Oxygen-fired combustion may also be implemented in power systems in which gaseous fuels are combusted with oxygen in the presence of recycled water to produce a steam/CO2 turbine drive gas. Water is condensed from the steam/CO2 exiting the turbine, leaving sequesterable CO2."

Note: Clean Energy Systems, Inc. is demonstrating this concept at their 20MWth plant near Bakersfield, CA, with supporting funding provided by DOE.

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6.1.4 Carbon Capture Future Research Directions Add in:

Continue R&D efforts on the oxy-combustion technology at pilot-scale, leading to commercial scale-up for applications to existing and new pulverized coal and cyclone boilers. The R&D will focus on the overall cost reduction of oxy-combustion by improving oxygen production, boiler operation and steam conditions optimization along with flue gas purification, and CO2 compression and storage.

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"Develop oxy-combustors and high-temperature turbines for oxy-fuel Rankine cycle power systems. Using pure oxygen and recycled water in a turbine’s combustion chamber can enable 100% CO2 capture and long-term power generation efficiencies of 50-60 percent"

Note that Siemens Power Generation and Clean Energy Systems were awarded $19 million by DOE to develop these technologies under awards DE-FC26-05NT42645&6.

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We strongly support this chapter, particularly the sections on Geologic Storage (6.2) and Terrestrial Sequestration (6.3). Carbon capture and storage (CCS) is a perfect candidate for further climate technology RDD&D, as currently there are only three "industrial-scale" (i.e., 1 million tons of CO2 annually) storage projects in operation, in Norway, Canada and Algeria.8 Because commercialization of large-scale CCS integrated into major power plants is probably a decade or so away, We believe this to be a medium-term energy supply technology (see subsection III.H.2 below). It is ideally suited for government and private RDDD money, needing assistance in achieving demonstration and deployment in large power plant systems. Moreover, over time the costs of this technology will decrease, obviating the cost-benefit objection that some of its detractors have raised.

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Solicit and foster concepts that either build on current approaches or that offer entirely new pathways. Given the magnitude and urgency of the CO2 problem and the infancy of large-scale CO2 capture/storage, it is important to recognize that technologies may emerge that offer distinct advantages over present concepts. As an example, the point-source capture and storage SO2, another acid gas from fossil fuel combustion, is now commonly achieved by a process quite different from those emphasized above and from those initially considered.

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Biomass (cellulosic waste or energy crops) could be used to produce a char based fertilizer for sequestering carbon in soil. Biomass is pyrolyzed to produce a porous char and producer gas. The producer gas is shifted to produce hydrogen for ammonia production and energy. The char can absorb CO2 and NH3 to produce ammonium bicarbonate resulting in a long release nitrogen fertilizer. The fertilizer production process can be used to scrub CO2, NOx, and SO2 from flue gases. The net sequestration of carbon can offset the emissions from transportation, for example. The fertilizer can be used to improve the productivity of marginal land, and hence increase biomass productivity, and this can further contribute to the net extraction and sequestration of atmospheric carbon.

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"good" should be "goods"

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the phrase "time and space" could be made more specific. For example this bullet could be "determine how terrestrial systems" capacities can be manipulated to enhance carbon sequestration by increasing pool sizes, rates of increase, areal extent, or longevity.

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this bullet should also include relationships with "energy policy" to capture the carbon benefits of biofuels of several types.

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practices and techniques have climate impacts in addition to altering GHGs, in particular albedo and roughness changes that have been shown to be dramatic.

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this section on precision agriculture is fairly narrowly defined. First it only mentions C sequestration and not full carbon accounting or other GHGs. Secondly it should consider fallow reduction, including use of winter cover crops.

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"conserve" should be "conservation". This section should also consider GHGs in addition to CO2.

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it is interesting that there is work on natural and restored wetlands. The sequestration potential of created wetlands should also be a research topic.

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Section 6.4

This important section must first point out that the ocean, as part of the natural carbon cycle, is currently playing a critical CO2 mitigation role by passively absorbing significant amounts of the anthropogenic CO2 via air-to-sea diffusion. Without this uptake the planet would be at considerably great risk than it currently is. I have added or changed wording that summarizes this concept.

Secondly, while direct CO2 injection and ocean fertilization may be the approaches that have receive the most attention, they are by no means the only possible ocean strategies, nor should they be assumed to be the only ones worth considering. As an important strategic planning document for a national research effort that is still in its infancy, an effort to acknowledge and briefly consider other published ideas needs to be made. This should include the possibility that the best strategies or combination of strategies may have yet to be proposed. I have added words and sections that provide a broader sense of these possibilities as well as their uncertainties.

I have added a list of references that document the preceding ideas.

Finally, I have offered some rewordings that may help clarify certain topics. Details are as follows:

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Power-plant flue gases could be used to dissolve limestone and the resulting solution could be placed in the ocean without harming ocean biota or causing ocean acidification.

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Because of the large CO2 storage capacity of the ocean, increasing the carbon uptake and storage of carbon in the oceans cannot be ignored. Indeed, the ocean is currently playing an important role in consuming significant amounts of anthropogenic CO2 via passive air-sea exchange, biological uptake, and ocean mixing (e.g., Sabine et al., 2004). Unfortunately, this natural CO2 uptake (about 7.3Gt CO2/yr) is not keeping pace with current anthropogenic emissions, and the ocean acidification that is accompanying the air-sea flux will have undesirable environmental consequences if allowed to continue (e.g., Caldeira and Wickett, 2003; Feely et al., 2004; Orr et al., 2005).

To understand the additional role the ocean could play in mitigating CO2, several

issues must be addressed, including the capacity of the ocean to sequester CO2, its effectiveness at reducing atmospheric CO2 levels, the depth and form (e.g., molecular or chemically bound, gas, liquid or solid) for introduction of the carbon, and the potential for adverse environmental consequences. Ocean storage has not yet been deployed or thoroughly tested, but there have been small-scale field experiments and 25 years of theoretical, laboratory, and modeling studies of intentional ocean storage of CO2. Nevertheless, much more needs to be learned about the potential environmental consequences to ocean ecosystems and natural biogeochemical cycles.

While there are a variety of potential ocean carbon sequestration options (see "Future Research Directions"), two strategies have received the most attention: (1) direct injection of a relatively.....

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Over the period of centuries, the oceans will passively take up about 70 percent of global fossil carbon emissions as CO2 diffuses into the ocean, is transported across the ocean thermocline, and mixed into deep ocean waters (IPCC 2001a). Intentional direct injection of captured CO2 would seek to augment to this natural CO2 flux to the deep sea and thus more rapidly slow or reverse the atmospheric CO2 increase. The potential for the ocean to absorb CO2 over the long term is large relative to that which would be generated by fossil-fuel resources. But several factors may affect the capacity and desirability of direct injection. Unless consumed by biological or chemical processes, excess CO2 placed in the deep sea will eventually via diffusion and ocean circulation interact with the atmosphere, adding some part of the injected CO2 to the atmospheric burden. For example, injection of about 8000 Gt CO2 to the deep ocean will eventually produce atmospheric CO2 concentrations of about 750 ppm, even in the absence of additional CO2 release to the atmosphere (citation?). It has been shown in experiments and models that high concentrations of CO2 depress ocean pH, and thus harm marine organisms and biogeochemical processes (e.g. Portner et al. 2004; TRS, 2005), but the true scope and magnitude of such effects need further study. Alternatives to direct injection and fertilization have been proposed for CO2 mitigation strategies, and while they can avoid the preceding concerns, they may have environmental , capacity, and cost limitations of their own (see "Future Research Directions").

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Ocean carbon sequestration offers the potential to significantly reduce CO2 concentrations in the atmosphere.

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Fertilization of the oceans with iron, a nutrient whose low concentrations in the open ocean frequently limit phytoplankton growth, is another strategy being considered. Here fertilization enhances marine photosynthetic draw-down of ocean and hence atmospheric CO2 and thus potentially accelerates the transfer of carbon to the deep ocean via sedimentation of some of the biomass formed (collectively - the "biological carbon pump"). Such fertilization will therefore manipulate and affect surface ocean ecosystems and will in turn expose the deep-sea to increases in sedimentary organic loading coupled with elevated CO2 concentrations and depressed oxygen levels as at least some of the sedimented biomass is oxidized back to CO2. Thus, while direct injection is likely to produce acute chemical and biological effects in the local region of injection, iron fertilization could produce ecosystem shifts over large areas of the surface and deep ocean. Alternative ocean carbon storage methods can lessen or avoid these impacts (section 6.4.4).

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Alternative ocean CO2 mitigation strategies (see "Future Research Directions") pose a different set of environmental and efficacy concerns that need to be evaluated should those of direct injection and fertilization prove to be unacceptable.

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6.4.4 Ocean Sequestration Future Research Directions. Add in:

Indirect Injection - A potentially more permanent and environmentally safer carbon sequestration alternative to direct injection involves contacting combustion-generated flue gas of fossil-fuel power plants with limestone and seawater. CO2 contained in the exhaust gases dissolves in water and reacts with limestone to form bicarbonate for release and sequestration in the ocean. This approach significantly reduces the acidification of the local environment compared with that of direct injection. Upon mixing and dilution with additional seawater in the ocean, the pH and the concentrations of dissolved calcium and CO2 will return nearly to background levels. Pilot-scale CO2 capture and sequestration performance testing as well as safety and environmental assessments must be conducted prior to large-scale implementation. Biological responses of selected marine organisms to the aqueous effluents should be evaluated.

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• Enhancement of Chemical CO2 Uptake. The uptake of CO2 by an aqueous solution can be enhanced by the addition of OH- and/or CO3- ions. Thus, Kheshgi (1995) pointed out that this could be done on a large scale by adding lime (CaO or CaOH) to the ocean to facilitate its abiotic CO2 uptake from the atmosphere via the reaction: CaOH + CO2 Ca2+ + HCO3-. Importantly, this form of CO2 mitigation would; 1) avoid the need for point-source CO2 capture, separation, and purification (unlike direct injection, but similar to ocean fertilization), 2) prevent increased ocean acidity because the added CO2 is neutralized to calcium bicarbonate dissolved in seawater, and 3) permanently store the added carbon in an ionic from that is already abundant in the ocean and not easily degassed back to the atmosphere. The concerns with this approach include the cost and carbon intensity of producing lime from the calcination of limestone, its transport to and dispersal in the ocean, and the environmental consequences of doing so. All of these issues require further study.

• Enhanced Carbonate Weathering. Rau and Caldeira (1999; 2002) suggested employing the spontaneous geochemical reaction CO2 + H2O + CaCO3 - Ca2+ + 2(HCO3-) to directly react CO2 out of waste gas streams and to place the resulting dissolved calcium bicarbonate ions in the ocean. Again this would avoid the need for molecular CO2 capture and purification and would convert most of the CO2 to relatively benign, ionic species. Modeling studies showed that such carbon storage would be effective for thousands of years and with far less impact to ocean pH than directly injecting a comparable quantity of carbon as molecular CO2 in the ocean (Caldeira and Rau, 2000). Initial cost estimates have shown that for treatment of coastal CO2 point sources this form of CO2 mitigation would be less expensive than more conventional molecular CO2 capture and geologic storage (Sarv and Downs, 2002; Rau et al., 2004). However, the true cost, capacity, effectiveness, and environmental impact of this approach need further evaluation.

• Ocean Burial of Crop Residue. It has been suggested that organic waste from agriculture be actively buried on the ocean floor, thus enhancing the natural air-to-land-to-ocean carbon sink represented by plant production, soil formation, soil erosion and river transport to the sea (Metzger and Benford, 2001). This approach would prevent some if not most of the oxidation of residue biomass on land and thus eliminate the resulting flux of CO2 back to the atmosphere. Ocean sites with existing permanent anoxia (e.g. offshore from major river deltas) could be used to slow or avoid oxidation of the biomass once on the ocean floor prior to its permanent burial by natural sedimentation. Concerns to be more thoroughly addressed include: 1) the cost of collecting, bundling, transporting, and sinking the residue, 2) the consequences to the fertility of the remaining cropland, and 3) the ultimate impacts to the marine environment.

• Ocean Disposal of CO2 Emulsions. Golomb et al. (2001; 2004) has shown that CO2 can form a dense emulsion when combined CaCO3 (e.g., limestone) particles under pressure. Such emulsions could be formed prior to or during ocean CO2 injection, with the resulting CO2-rich mass sinking to and stored on the ocean floor. Studies suggest that at deep ocean temperatures and pressures the CO2 might be sequestered indefinitely by this approach. The method and cost of: 1) initial CO2 capture and purification, 2) limestone/carbonate preparation, 3) transporting reactants to ocean sites, as well as the marine environmental consequences of this approach are among the issues that remain to be addressed in detail.

• Other Methods. The preceding list of CO2 mitigation options involving the ocean may not be exhaustive, and any future research portfolio must be open to the possibility of new approaches or mix of approaches.

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of sequestration could provide many options for a future of reduced or near-net-zero GHG emissions. Carbon sequestration will hopefully be able to contribute to safe, cost-effective stabilization of GHG concentrations in the atmosphere, thus further supporting domestic and global economic growth based on fossil fuels. Although an energy

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non-fossil energy sources is required. For the preceding reasons CO2 capture and storage must be viewed as an essential part of a global, low-carbon-intensity energy future.

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Specific Comments on Chapter 7.3 Emissions of high global-warming potential gases

The Current Portfolio section 7.3.2.3 and Future Research Direction section 7.3.2.4 includes research on the 'aluminum industry - perfluorocarbon emissions' that addresses anode effect research and R&D for an inert anode. These efforts should continue due to their high potential to improve energy efficiency and reduce PFC emissions. Much progress has been made on reducing anode effects reducing PFC emissions in the U.S. primary aluminum industry by over 46 percent. Production of an inert anode can eliminate associated PFC emissions and increase energy efficiency by up to 25 percent.

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We were pleased to see that the draft plan recognizes the waste management sector as presenting some of the most promising and cost-effective opportunities for reducing GHGs. However, the draft plan fails to recognize the significant GHG reductions already achieved by the industry. Since the mid-1970s, technological advancements, environmental regulations, and emphasis on recycling, composting and energy recovery have significantly reduced the environmental impacts of municipal solid waste management, including GHG emissions, even as the amount of solid waste managed has grown nearly two-fold.

Changes in waste management practices over the past 50 years that have resulted in decreased GHG emissions include:

• Increased recycling and composting rates.

• Increased combustion of municipal solid waste and waste biomass to produce energy.

• Increased collection and control of landfill gas.

• Transitioning of refuse collection fleets to alternative fuel vehicles.

Various studies have estimated that changes in solid waste management practices have resulted in a 50 to over 80 percent reduction in GHG emission compared to what would have occurred without implementation of these improved waste management practices. Despite the range of estimated reductions, it is clear that improvements in solid waste management practices have already resulted in some of the largest percentage reductions in GHG emissions accomplished by any sector of the US economy. EPA’s most recent study, the 2005 U.S. Inventory of Greenhouse Gas Emissions, estimated that between 1990 and 2003, methane emissions from landfills had been reduced by 40 percent. (Note: the % Change in methane emissions figure for landfills in Table 7-3 is incorrectly shown as -24%.)

The Draft Plan Should Incorporate Development of Streamlined Permitting Approaches to Foster New Renewable Energy Projects

We are at the forefront of producing clean renewable energy from landfill gas-to-energy (LFGTE) projects, which minimize emissions of greenhouse gases, as well as generate either electricity or fuel for beneficial uses. We operate 58 landfill gas-to-electricity projects that generate 264 megawatts of electricity – enough to power 238,000 households. We also operate 34 landfill gas-to-fuel projects that generate nearly 16 million MMBTU of fuel or the equivalent of nearly 3 million barrels of oil.

We believe that market forces that increase the value of landfill-gas will drive increasing numbers of gas collection and beneficial use projects, as well as increased gas collection efficiency. Nonetheless, significant environmental regulatory barriers exist to siting new landfill-gas projects. These barriers are neither acknowledged, nor addressed in the draft plan. We recommend that DOE work with its partner agencies and make the development of streamlined permitting options for LFGTE projects a priority in the draft plan.

Obtaining the necessary federal, state and local air quality permits can pose major obstacles to developing viable LFGTE projects. A complex array of standards can potentially affect LFGTE projects including: New Source Performance Standards for municipal solid waste landfills and stationary turbines, as well as National Emission Standards for Hazardous Pollutants, which affect LFG collection and control equipment; New Source Review or Prevention of Significant Deterioration, which may entail air quality impact analyses, obtaining offsets for emission increases, implementing the most stringent and expensive controls (LAER/BACT) on project equipment, and alternate site analyses; and Title V, which could subject LFGTE facilities to an extensive permitting process that includes a comprehensive emissions inventory, regulatory applicability review, compliance certification and substantial public involvement. State and local authorities may also impose provisions for construction and operating permits, source-specific requirements, and various other regulatory elements. Complying with this dizzying array of regulatory requirements can be very expensive, making an otherwise viable LFGTE project uneconomical. The draft plan’s technology strategy for promoting LFGTE projects should incorporate the development of streamlined permitting approaches that allow federal, state and local regulators to balance air quality goals with the other environmental benefits offered by these projects.

The Draft Plan Should Delineate Specific Research for Promoting Bioreactor Technology

As a leader in the research, development and demonstration of bioreactor landfill technology, We strongly support the CCTP draft plan’s focus on bioreactors. We are committed to the development and adoption of bioreactor landfills as demonstrated by our joint work with EPA. We have engaged in a Cooperative Research and Development Agreement (CRADA) with EPA to determine which practices best promote the safe operation of large-scale bioreactor landfills, and we are participating in EPA's Project XL, an initiative that involves pilot projects to demonstrate superior environmental performance from using bioreactor landfill technology. We are also very supportive of bioreactor development work DOE has engaged in with Yolo County and the Environmental Research & Education Foundation to develop and demonstrate bioreactor technology at the Yolo County and Northern Oaks landfills.

We recommend the draft plan highlight specific work to demonstrate the potential of bioreactor landfill technology for reducing non-CO2 greenhouse gas emissions by focusing on the following areas: concentration and capture of methane; improved gas collection and control systems; and use of alternative cover materials to control fugitive emissions.

Bioreactors landfills are expected to concentrate methane generation to a shorter time frame and facilitate the capture of more methane than conventional landfills, assuming the total methane generating potential of the solid waste is constant. Providing funding to demonstrate that these benefits are actually being achieved in the RD& D projects that are underway or planned would provide important validation of this technology and promote its more widespread use.

Improved landfill gas collection and control systems can provide significant non-CO2 emissions reductions for both conventional and bioreactor landfills. DOE’s funding to demonstrate the Intelligent Bioreactor Management Information System (IBM-IS) for the control of fugitive landfill gas emissions from an anaerobic bioreactor landfill at Yolo County is an important first step. We recommend that the draft plan include in its research agenda the installation of improved gas collection and control systems in new bioreactor landfill construction. Bioreactor landfills are required to install gas collection systems prior to adding liquids and this provides an opportunity to improve gas collection efficiency by designing systems that can be installed as the landfill is constructed rather than the traditional approach of drilling vertical wells after the landfill is completed. Research on the design, construction and operational effectiveness of horizontal wells, permeable layers and other new gas collection systems would be very beneficial.

Another fruitful area of research that should be identified in the plan is the reduction of methane emissions from old or small landfills, by using catalysts, aeration or optimization of oxidation in landfill cover systems. Funding for demonstration projects on optimizing methane oxidation by cover soils or materials impregnated with methanotrophic bacteria has been useful in promoting these near-term technologies.

Finally, the draft plan should address an important barrier to promoting the widespread use of bioreactor technology, which is the regulatory barrier posed by the Resource Conservation and Recovery Act (RCRA) regulations for municipal solid waste landfills. RCRA regulations preclude a number of practices inherent to creating a bioreactor landfill, and it is only through EPA’s development of an RD&D Rule, that bioreactor landfill technology can be tested in states that adopt the rule. However, the regulatory flexibilities granted by the RD&D Rule are only available for a twelve-year period. Since the life of a landfill extends well beyond twelve years, this creates a great deal of uncertainty for companies or municipalities that would like to take advantage of the potential benefits of the technology, and is a serious barrier to the technology’s widespread use. Preliminary discussions have been held among leading landfill academics, consultants, owner/operators and trade groups to organize a specialty symposium in 2008 with the objective of providing a forum for high quality peer-reviewed research on bioreactor landfills that will support EPA’s final rule making process to revise the RCRA standards to accommodate bioreactor technology. The DOE’s support of such a symposium through the CCTP would be very helpful.