Activities relating to energy in China have focused on identifying opportunities for early CCS action and exploring the relevance of the CBTL concept to China.
Opportunities for early CCS action
The urgency of widespread deployment of CCS technologies for coal power generation in China is underscored by the huge growth rate for coal power—almost 100 GW of new coal capacity was added in 2006, equivalent to almost 1/3 of total installed capacity for coal power in China in 2004—and the fact that CCS is much less expensive for new power plants that for retrofit strategies at existing power plants.
Our activities in this area over the past year have been largely in conjunction with international meetings.
In April 2007, Larson gave an invited talk in Beijing at a workshop on CCS and enhanced oil recovery (EOR) organized jointly by BP and PetroChina. Larson’s presentation emphasized the relatively low costs of CO2 from coal gasification systems and the potential attractiveness of utilizing such CO2 for EOR.
In May 2007 Williams participated in a Joint Workshop on the Industrial Alliance for IGCC and Coproduction and CO2 Capture and Storage in Beijing, cosponsored by the Energy Technological Innovation Project at Harvard and the Institute of Thermo-Engineering Physics of the Chinese Academy of Sciences. Williams was asked to review CO2 capture activities in the U.S. In his presentation he described the U.S. petcoke IGCC with CCS projects coupled to enhanced oil recovery (BP Carson Refinery project in California and Goldman-Sachs Lockwood Project in Texas) and growing US interest in coal to liquids technology coupled to enhanced oil recovery. He also showed how over the last two years all power generation capital costs and thus CO2 capture costs have escalated dramatically as a result of the worldwide scarcity of steel, copper, cement, etc., and skilled construction labor. And he highlighted the findings of earlier CMI research (Meng, Williams, and Celia, 2007) that plants making ammonia from coal represent attractive opportunities for early CCS demonstration projects in China.
In November 2007 Williams was invited to participate at the World Bank in a Roundtable on Innovative Strategies to Accelerate the Development of Clean Energy Technologies. The Roundtable was intended to solicit advice relating to the World Bank Group’s Clean Energy for Development Investment Framework Action Plan, which outlines some of the key activities the Bank intends to undertake in the area of mitigating greenhouse gas emissions and helping client countries adapt to changes in climate. Williams highlighted the potential opportunities for demonstration projects using the relatively low-cost CO2 available at plants that make methanol, dimethyl ether, or ammonia from coal. This World Bank group was especially interested in the ammonia plant opportunities highlighted in our earlier work (Meng, Williams, and Celia, 2007).
Is CBTL with CCS relevant to China?
There have been many proposals for building coal to liquids (CTL) plants in China, and for none of these is CCS being planned. As a result, the fuel-cycle-wide GHG emission rate would be approximately twice the rate for crude oil-derived fuels. So finding a way to get CCS underway for coal synfuels is important for mitigating climate change. However, even if CCS were to be carried out at CTL plants, the GHG emission rates would be no better than for crude oil-derived hydrocarbon fuels replaced.
As an element of our collaboration with Li Zheng’s group at the BP-Tsinghua Clean Energy Center in Beijing, we have begun to explore the prospects for extending to China the concept of making low GHG-emitting synthetic fuels from coal + biomass (CBTL) with CCS. Professor Li hosted a 12-month visit by Cathy Kunkel3 at Tsinghua University beginning in the fall of 2006. During this period Kunkel, supervised by Larson and interacting with Prof. Li and others at Tsinghua, gathered data and carried out preliminary analyses relating to these coal/biomass coprocessing strategies for low-carbon liquid fuels supply in China—considering as feedstocks both crop residues (from agriculturally-rich Shandong Province) and mixed native prairie grasses (from Inner Mongolia). Both regions have coal resources.
For crop residues4 the focus has been on developing a comparative analysis of alternative cooking fuel strategies for rural households—motivated largely by concerns about severe adverse health impacts of indoor air pollution from the direct burning of coal or crop residues for cooking. The analysis is comparing health impacts, cooking fuel costs, and GHG emissions for six cooking fuel strategies: (i) direct coal burning, (ii) direct crop residue burning, (iii) burning pelletized crop residues in cleaner-burning stoves, (iv) burning dimethyl ether (DME) produced from crop residues via gasification, (v) burning DME produced from crop residues + coal via gasification, and (vi) burning DME from coal via gasification. For the options involving coal, both CO2 venting and CCS approaches are being considered. This analysis includes developing models of the logistical costs of crop residue collection and delivery under conditions for Shandong Province.
The case of Inner Mongolian prairie grasses used for coal/biomass-based synfuels production involves developing an extensive biogeophysical database for Inner Mongolia that includes current grassland yields, potential yields if degraded lands are restored, the locations of major coal deposits and potential underground CO2 storage sites, and other relevant data. Grasslands account for about 40% of China’s land area, and 30% of China’s grasslands are in Inner Mongolia—much of which are heavily degraded and the restoration of which is a high political priority in China. Although yields on restored grasslands in Inner Mongolia are low (~1.5 tonnes per hectare per year on average) preliminary calculations suggest plausibly attractive economics for farmers growing grasses for energy relative to what they are doing with the land at present—if the oil price is high and the value of CO2-equivalent GHG emissions is high (at least ~ $30/t CO2).
A new dimension of the China grasslands work is interest in these issues on the part of an internationally known ecologist, Jianguo (Jingle) Wu (a faculty member at Arizona State University), who works on the ecology of Inner Mongolian grasslands restoration (and is originally from Inner Mongolia). A meeting took place in Beijing in March 2007 involving Wu, Kunkel, Li Zheng, Gary Dirks (CEO of BP Asia and a personal friend of Jingle Wu), and Steve Wittrig (who manages BP’s academic research investments in China). Larson, Kunkel and Williams prepared background materials for the meeting, and at the meeting Dirks expressed strong interest in exploring further the idea of utilizing grassland biomass for liquid fuels. He suggested trying to pique the interest of the Shenhua Corporation, which is planning the construction of several coal-to-liquids plants in China and is already building the first one in Inner Mongolia. Subsequently (in April 2007), as a result of arrangements made by Jingle Wu, Larson and Kunkel met with key researchers at the Institute of Botany of the Chinese Academy of Science (Beijing) and at the University of Inner Mongolia (Hohuhot), the two leading centers for research on restoration of degraded grasslands. The purposes of these meetings were to collect data and establish contacts for possible future collaborations.
During the coming year, Larson will lead efforts to finish and publish the two pieces of analysis that were initiated with Kunkel5 and to search for an outstanding candidate to take up residence with Prof. Li’s Group to continue the work Kunkel began.
3. Princeton ’06 graduate with high honors in physics.
4. Of which ~ 360 million tonnes are potentially available annually for energy in China.
5. Who in the fall of 2007 started graduate work in physics at Cambridge University, UK.