Ken, List etal: I enjoyed the short video. Thanks to Ken for alerting us. I recommend looking at four others by Near Zero with Mr/Dr. Simbeck- that also have some relation to geoengineering. Here are more thoughts (on all five videos), with advance apologies for turning the dialog to Biochar, but all the following thoughts came from four of the five videos.
1. I have known for decades that biomass electric systems were inefficient, but not that it was due to water production (and still surprised that biomass is that different from coal). So the Simbeck argument for co-firing in a BECS operation makes some sense. But in a Biochar-oriented use of the same fuel resource, I believe the pyrolysis gas can be of quite high (water-free) quality. This is especially if there is a prior electrolysis step (using wind/solar) so air is replaced by O2 and the H2 is combusted. I think this pyrolysis gas can be arranged to have no water in the pyrolysis gas stream - even if the incoming biomass is not bone dry. These next three cites given me some hope that we can get the electrical efficiency above 35% - even in a very small (gas turbine) power plant. ttp://www.fpl.fs.fed.us/documnts/techline/wood-biomass-for-energy.pdf http://www.nasw.org/users/nbazilchuk/Articles/McNeil.htm http://www.iea.org/techno/essentials3.pdf Q1 - Is there anything technically wrong so far? Can we get to 35 or 40% electrical generator efficiency with a biomass input - and char output? (I gather there is an IGCC plant in Sweden doing at least part of this.) 2. The Simbeck argument was for co-firing in part because of the appreciably higher existing efficiencies of large scale coal plants. But that same argument works against cogeneration - or combined heat and power (CHP - which Mr. Simbeck argues for in a different video). Biochar plants are almost always assumed to be small - because of the transportation costs - the same argument which led Mr. Simbeck to argue for a 10% maximum share for biomass in co-firing. Q2. Again - anything wrong for striving for CHP - but with a simultaneous char output (assumed to be economically superior to combustion for combined soil and sequestration char-reasons)? 3. There is also a Simbeck video dealing with his exasperation over the slow global progress on CCS. In the BECS talk there is no mention of this CCS side of the obvious advantages of sequestering in a carbon negative rather than carbon-neutral fashion. I personally now doubt we will ever see CCS - and therefore not BECS either. But that is a different story - basing my feeling on indemnification and other legal issues - as well as the obvious reluctance of anybody to be the first. . Q3. Is there any fundamental reason that BECS can't/shouldn't be added to an operating Biochar-based CHP plant? (I am asking if the funds for CCS are apt to be better spent on additional Biochar plants, assuming sufficient biomass somewhere to justify the release of half the initial carbon (that was exploited in carbon-neutral fashion). This is sort of like the recent putdown by Dr. Socolow in the APS report on artificial trees (direct air capture) Where is the more likely biggest bang for the buck? ) 4. The fourth video deals with the future fossil supply (with a mixed message) that should scare most on this list - but I can't tie this talk to either BECS or Biochar specifically. But the fifth video deals with relationships between government and industry. He specifically talks of Rangefuels - a firm near me. I don't know enough on the technology (I have tried), but wonder if anyone can tie this (fuels) technology to either BECS or Biochar? Since Biochar now has almost zero Federal funding (and that for CCS has been huge), I hope we can talk here about the role for Federal funding for Geoengineering in general - where the only income (unlike CCS) is apt to be from government. Fortunately Biochar is teeming with (small) entrepreneurs - but I don't see them getting much help from the government (except maybe there will be some from places like China and India.) Q4. Is the CDR arena different in a fundamental way from biofuels? Again thanks to Ken and NearZero for bringing this series to our attention. Ron 4. ----- Original Message ----- From: "Ken Caldeira" <kcalde...@carnegie.stanford.edu> To: r...@llnl.gov Cc: "Dave Hawkins" <dhawk...@nrdc.org>, "geoengineering" <geoengineering@googlegroups.com> Sent: Wednesday, August 3, 2011 1:52:12 PM Subject: Re: [geo] CO2 mitigation via biomass-coal co-firing? Folks interested in biomass cofiring of power plants might want to watch this little YouTube video we produce of Dale Simbeck speaking on this issue. Biomass blended with coal: Dale Simbeck speaks to Near Zero http://www.youtube.com/watch?v=wCnYcSC0PZM While I am sending out YouTube links, you might also be interested in a video of my post-doc Julia Pongratz talking about a paper that came out yesterday on the mitigation potential of reforestation: Past land-use decisions and the mitigation potential of reforestation: Dr Julia Pongratz http://www . youtube .com/watch?v=Bmyek4gYEUk On Wed, Aug 3, 2011 at 12:01 PM, Rau, Greg < r...@llnl.gov > wrote: Thanks, Dave. Roger that. Full environmental cost/benefit accounting (and sustainability) for biomass is trickier than the current market euphoria would suggest. Abiotic carbon mitigation must also be considered, esp since this is the way nature will otherwise consume nearly all of our excess CO2. Meanwhile: BIOFUELS: Coal power plant in U.K. could become top renewable energy source (08/03/2011) The largest coal power plant in the United Kingdom could become the biggest source of renewable energy by burning more straw and other biomass, if government subsidies are increased. In the first half of this year, the Yorkshire-based Drax plant produced about 6 percent of the United Kingdom's total renewable power. Dorothy Thompson, chief executive of the power station, said Drax currently runs at 8 percent capacity but could achieve up to 50 percent with greater subsidies for biomass. "The level of financial support is inadequate to burn biomass in very large quantities at current market rates," she said. By burning carbon-neutral bio-waste instead of coal, the Drax facility could have a smaller carbon footprint than gas-fired power stations. If offered government support, Thompson said, the plant could be delivering renewable energy to t2 million homes by 2020. Meanwhile, U.K. government ministers are looking to move away from coal and cut carbon dioxide emissions while avoiding potential power shortages. Chris Huhne, secretary of state for energy and climate change, said, "Biomass is one of the cheapest ways of meeting our renewable energy targets, but the key issue is setting the level of support -- enough to deliver what is needed, but not too much, or that becomes an unnecessary price for the end-user to pay." Drax, which released its half-year financial report yesterday, was aided by a one-time £198 million ($323 million) tax credit. This will go a long way in converting the plant's coal-fired boilers to predominantly biomass generators. Huhne said the government will complete a review of its subsidy program by later this year (Fiona Harvey, London Guardian, Aug. 2). -- JP On 8/2/11 2:14 PM, "Dave Hawkins" < dhawk...@nrdc.org > wrote: > Two points. > > In the carbon mitigation option supply curve there are lots of options > that get minor to modest reductions at low costs per ton. But trying to > use these techniques to achieve large reductions typically escalates the > costs per ton, if large reductions are even technically achievable. So > the biomass/CCS comparison by the RAND engineer is an apples-to-oranges > comparison. > > Second, as my colleague Nathanael Greene points out, without > lifecycle-based accounting criteria for biomass used for energy > purposes, GHG emissions can increase for decades before the benefits of > the substitution of fossil fuels become large enough to pay back the > carbon debt produced by harvesting the carbon sequestered in biomass. > The US (and other countries) are not off to a good start in developing > sustainable accounting provisions for biomass use. Biomass producers > waged political war against EPA's attempts to implement full life-cycle > GHG accounting for biomass energy resources. > > Biomass use can be an important mitigation tool but it is important to > do it right. The lesson to date is just because it is technically > possible to "do it right" does not mean that it will be done right. > That's a lesson to keep in mind for (other) geo-engineering concepts > too. This is not an argument against geo-engineering; just a reminder > that making a concept effective in the real world involves more than > coming up with an effective technological approach. > > -----Original Message----- > From: geoengineering@googlegroups.com > [mailto: geoengineering@googlegroups.com ] On Behalf Of Rau, Greg > Sent: Tuesday, August 02, 2011 3:56 PM > To: geoengineering > Subject: [geo] CO2 mitigation via biomass-coal co-firing? > > "According to DOE's estimates, it would cost $94 per metric ton of > carbon dioxide to abate carbon emissions using carbon capture technology > in older, subcritical coal plants. In comparison, it could cost as > little as $16 per metric ton to abate carbon if 5 percent of coal supply > were replaced with locally sourced woody biomass." > > RENEWABLE ENERGY: Adding biomass to coal much less expensive than carbon > capture -- study (08/02/2011) > Tiffany Stecker, E&E reporter > Faced with increasing pressure to reduce carbon emissions, coal-burning > power plants may be better off adding biomass to the energy mix rather > than waiting for expensive carbon capture and storage technology, a > study suggests. > > Shrinking greenhouse gas emissions with biomass from forestry waste, > logging residues or commercially produced wood pellets costs a fraction > of what carbon capture and storage technology abatement would, states a > report from the RAND Corp. The report is the fourth in a series prepared > for the Department of Energy on the technical aspects of using biomass. > > According to DOE's estimates, it would cost $94 per metric ton of carbon > dioxide to abate carbon emissions using carbon capture technology in > older, subcritical coal plants. In comparison, it could cost as little > as $16 per metric ton to abate carbon if 5 percent of coal supply were > replaced with locally sourced woody biomass. > > Even if a plant chose to use pellets, about three times more expensive > than locally sourced biomass, it would cost about $56 per metric ton of > CO2 to abate the carbon emissions -- 40 percent less than for carbon > capture and storage. > > Even in the high-priced scenarios, "if you remove the [margin of > uncertainty], it's still reasonably priced as compared to carbon capture > and sequestration," said David Ortiz, lead author of the study and an > engineer at RAND. "It ends up still being a cost-effective way to do > this." > > The researchers assessed three different percentages of biomass supply > to replace coal: 2 percent, 5 percent and 10 percent. They applied these > three figures for three different biomass mixes. Woody biomass from > local sources costs $40 per dry metric ton. Factory-made pellets from > switch grass and corn stover cost three times as much -- $120 per metric > ton. A mix of both costs about $62 per metric ton. > > Carbon capture and storage technology involves capturing carbon > emissions from a plant and storing them underground. While pilot > projects are in operation around the world, the technology has yet to be > commercialized. > > Cutting renewable costs has its limits > The benefits of using biomass for renewable energy are visible. Wood is > plentiful, state and federal programs to promote the method are growing > and, compared to building infrastructure for wind turbines or solar > panels, combusting biomass is far less expensive. > > But older power plants can only accept up to 10 percent biomass, a big > limiting factor to the greenhouse gas-saving potential, said Ortiz. In > addition, grinding biomass for use in boilers requires additional energy > -- electricity that could instead be sold to utilities. > > Biomass can also slow down a plant's efficiency, all for less energy > output than burning coal. Even when burning high-energy density pellets > in a 5 percent mix, it would cost a plant an additional 6.9 cents per > kilowatt-hour. > > "You can't get around the fact that you're going to need additional > energy," said Ortiz. > > While many state renewable energy tax credit systems favor biomass > energy, Ortiz suggests that the rate be flexible according to feedstock > choice. > > "The cost of producing electricity in coal-firing is so variable on the > price of fuel that a renewable energy credit may all of a sudden not > become an attractive option," he said. > > Makes sense 'if you're going to burn it anyway' > The carbon savings of biomass have also been questioned by environmental > groups, which claim that carbon emissions from combusting wood has no > advantage over burning fossil fuels. A study commissioned by the state > of Massachusetts released last year found that switching from coal to > biomass could increase the state's carbon emissions 3 percent by 2050 > (Greenwire, June 11, 2010). > > Nevertheless, U.S. EPA ruled last month to allow biomass plants a > three-year exemption from regulations for greenhouse gas emissions. > > It could take up to 100 years for the world's trees to make up for > biomass emissions by sequestering carbon dioxide through photosynthesis, > said Nathanael Greene, director of renewable energy policy with the > Natural Resources Defense Council. > > The only time when woody biomass makes sense, he said, is if loggers > sell timber leftovers that would otherwise be burned in an open pit. > > "If you're going to burn it anyway, burning it in a power plant is > obviously better," he said. "But there's not much of that out there." > > "We shouldn't be making a choice between mountaintop removal and > chopping down forests," he added. "We have better options." -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To post to this group, send email to geoengineering@googlegroups.com . To unsubscribe from this group, send email to geoengineering+unsubscr...@googlegroups.com . For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en . -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To post to this group, send email to geoengineering@googlegroups.com. To unsubscribe from this group, send email to geoengineering+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en. -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To post to this group, send email to geoengineering@googlegroups.com. To unsubscribe from this group, send email to geoengineering+unsubscr...@googlegroups.com. 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