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One of the leading alternatives for producing clean power from coal -- Integrated Combined Cycle Gasification (IGCC) technology faces a precarious future due to rising capital costs and regulatory uncertainty. A process of gasifying coal that allows capture of carbon dioxide emissions, IGCC has tremendous potential for meeting future baseload generation demand but project momentum has slowed dramatically in 2007, according to a new study from Emerging Energy Research (EER). Despite delays or cancellations of several prominent IGCC projects in 2007, 48 projects with a combined capacity of over 25,000 MW remain in the global IGCC pipeline, according to EER.

The effects of combined driving and vehicle-to-grid (V2G) usage on the lifetime performance of relevant commercial Li-ion cells were studied. We derived a nominal realistic driving schedule based on aggregating driving survey data and the Urban Dynamometer Driving Schedule, and used a vehicle physics model to create a daily battery duty cycle. Different degrees of continuous discharge were imposed on the cells to mimic afternoon V2G use to displace grid electricity. The loss of battery capacity was quantified as a function of driving days as well as a function of integrated capacity and energy processed by the cells. The cells tested showed promising capacity fade performance: more than 95% of the original cell capacity remains after thousands of driving days worth of use. Statistical analyses indicate that rapid vehicle motive cycling degraded the cells more than slower, V2G galvanostatic cycling. These data are intended to inform an economic model.

After safety, the longevity of the batteries in a plug-in hybrid is the greatest unknown. Can a plug-in hybrid’s battery pack retain the bulk of its energy capacity over 10 years of daily use and more than 4000 full-discharge cycles? (For a deeper look at the challenges facing plug-in hybrid batteries, see “Lithium Batteries Take to the Road”.)[ LINK: http://www.spectrum.ieee.org/sep07/5490 ] As Don Hillebrand of Argonne National Laboratory, in Illinois, said tartly, “Batteries are the showstopper.” Periodic demands from the grid, even for only a small fraction of the battery’s stored energy, would clearly affect the cells’ life span—but no one has data on how much. Another open issue is the development of creative financing models for replacement battery packs costing several thousand U.S. dollars even after mass production is achieved. Third-party battery leasing could be one answer, if combined with a secondary market for batteries whose performance has fallen below automotive levels. Carmakers, electric utilities, and large consumer-financing groups are quietly batting around these notions to see if they can build a financial model that makes sense for all three parties.