*Corresponding author. Tel.: 001-302-831-0049; fax: 001-302-831-
6838.
E-mail addresses: willett@udel.edu (W. Kempton), tkubo@aceee.org
(T. Kubo)
Energy Policy 28 (2000) 9}18
Electric-drive vehicles for peak power in Japan
Willett Kempton!,*, Toru Kubo"
!College of Marine Studies and Center for Energy and Environmental Policy, University of Delaware, Newark, DE 19716, USA
"American Council for an Energy-Ezcient Economy, 1001 Connecticut Ave, NW, Suite 801, Washington, DC 20036, USA
Received 19 August 1999
Abstract
Electric-drive vehicles (EDVs), whether based on batteries, engine-electric hybrid, or fuel cells, could make major contributions to
the electric utility supply system. Computer-controlled power connections from parked EDVs would provide grid power from
on-board storage or generators. Kempton and Letendre conclude that, in the United States, battery EDVs can be cost-e!ective as
a source of peak power (Kempton and Letendre, 1997) or as spinning reserves (1999). This option is even better matched to urban
Japan, where vehicles are typically parked throughout peak electrical demand periods. Using Ministry of International Trade and
Industry (MITI) forecasts for the number of zero emission vehicles in 2010, we estimate the maximum potential power 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 "ve current EDVs * both battery and hybrid vehicles * and compares those 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) projections. Given current vehicle battery costs and current utility purchase rates, no
vehicles would be cost-e!ective peak power resources. Given CARB projections for batteries, the Nissan Altra is cost-e!ective as
a utility power source. Using projected IPP purchase rates for peak power and CARB battery projections, the Nissan Altra