Electric-drive vehicles for peak power in Japan

Electric-drive vehicles (EDVs), whether based on batteries, engine-electric hybrid, or fuel cells, could make major contributions to the electric util ity supply system. Computer-controlled power connections from parked EDVs w ould provide grid power from on-board storage or generators. Kempton and Le tendre conclude that, in the United States, battery EDVs can be cost-effect ive as a source of peak power (Kempton and Letendre, 1997) or as spinning r eserves (1999). This option is even better matched to urban Japan, where ve hicles are typically parked throughout peak electrical demand periods. Usin g Ministry of International Trade and Industry (MITI) forecasts for the num ber of zero emission vehicles in 2010, we estimate the maximum potential po wer from EDVs in the Kanto region (which includes Tokyo) at 15.5 GW, 25% of Kanto's 1998 peak demand. This paper calculates the cost to provide power from five current EDVs - both battery and hybrid vehicles - and compares th ose costs to current purchase rates for independent power producers (IPPs) in Japan. Battery characteristics are calculated from current manufacturer- provided data as well as the California Air Resources Board (CARB) projecti ons. Given current vehicle battery costs and current utility purchase rates , no vehicles would be cost-effective peak power resources. Given CARE proj ections for batteries, the Nissan Altra is cost-effective as a utility powe r source. Using projected IPP purchase rates for peak power and CARE batter y projections, the Nissan Altra and Toyota RAV4L EV are cost-effective. The net present value to the electric grid could be near 300,000 yen ($US 2500 ) per vehicle. If utilities take advantage of this opportunity to purchase peak power from vehicles, it would make the electric grid more efficient, e nlarge the market for EDVs, lower urban air pollution, and facilitate futur e introduction of renewable energy. (C) 2000 Elsevier Science Ltd. All righ ts reserved.