Willett Kempton

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As the light vehicle fleet moves to electric drive (hybrid, battery, and fuel cell vehicles), an opportunity opens for “vehicle-to-grid” (V2G) power. This article defines the three vehicle types that can produce V2G power, and the power markets they can sell into. V2G only makes sense if the vehicle and power market are matched. For example, V2G appears to(More)
Vehicle-to-grid power (V2G) uses electric-drive vehicles (battery, fuel cell, or hybrid) to provide power for specific electric markets. This article examines the systems and processes needed to tap energy in vehicles and implement V2G. It quantitatively compares today’s light vehicle fleet with the electric power system. The vehicle fleet has 20 times the(More)
Executive Summary Electric-drive vehicles can become an important resource for the California electric utility system, with consequent air pollution, system reliability, and economic benefits. We refer to electric power resources from vehicles as "Vehicle to Grid" power (V2G). The economic value of some forms of V2G appear high, more than enough to offset(More)
The history of empirical research on the SapirWhorf hypothesis is reviewed. A more sensitive test of the hypothesis is devised and a clear Whorfian effect is detected in the domain of color. A specijic mechanism is proposed to account for this effect and a second experiment, designed to block the hypothesized mechanism, is performed. The effect disappears(More)
Grid-Integrated Vehicles (GIVs) are plug-in Electric Drive Vehicles (EDVs) with power-management and other controls that allow them to respond to external commands sent by power-grid operators, or their affiliates, when parked and plugged-in to the grid. At a bare minimum, such GIVs should respond to demand-management commands or pricing signals to delay,(More)
World wind power resources are abundant, but their utilization could be limited because wind fluctuates rather than providing steady power. We hypothesize that wind power output could be stabilized if wind generators were located in a meteorologically designed configuration and electrically connected. Based on 5 yr of wind data from 11 meteorological(More)
Wind power resources on the eastern U.S. continental shelf are estimated to be over 400 GW, several times the electricity used by U.S. eastern coastal states. The first U.S. developer proposes to build 130 large (40 story tall) wind turbines in Nantucket Sound, just outside Massachusetts state waters. These would provide 420 MW at market prices, enough(More)
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(More)
This paper describes a method for assessing the electric production and value of wind resources, specifically for the offshore environment. Three steps constitute our method. First, we map the available area, delimiting bathymetric areas based on turbine tower technology, then assess competing uses of the ocean to establish exclusion zones. From exclusion(More)
Access to an undefined variablmne which has never been assigned a valu-an be detected by automatic means. However, today’s compilers do not detect undefined variables comprehensively, and the environment dependence of these errors often allows them to evade normal testing procedures. Language standards for Pascal, Modula-2 and Ada specify the circumstances(More)