Knowledge Problem

Plug-in Hybrid Vehicles and the New York Electric Power System

Michael Giberson

The New York Independent System Operator – the folks the manage the electric power transmission system in the state – has released a report on the potential effects of plug-in hybrid vehicles (PHEV) on New York power systems  operations.  Given the very early stage of technology development – if there are any PHEV’s in the state now they are likely experimental research vehicles or hobbyist homebrews – a lot of the report comes down to saying “it depends on how things eventually work out.”

From the point of view of the power system, the most important issues concern how and where and when the vehicles recharge. As the report points out, consumer recharging choices will be significantly affected by retail rate designs. A flat rate means that consumers will not be dissuaded from adding to overall electric load at peak times, when the transmission system is congested and high-cost generation units must run to keep the system operating. Time-of-use rates or market-driven prices will encourage consumers to shift charging to off-peak periods.

The flat rate scenario will require additional investment in electric generation, transmission and distribution systems, while the more reasonable pricing systems may allow the power system to accomodate significant numbers of PHEV with little or no additional investment in supply-side capacity.

It should go without saying that smart grid systems (devices and commercial practices) could play a critical role in getting the most consumer value out of a PHEV.

The NYISO report draws from three much more detailed technology analyses, one by Oak Ridge National Laboratory, another by the Electric Power Research Institute  and the Natural Resources Defense Council, and the third by Pacific Northwest National Laboratory, and several other studies. Despite the tentative nature of the NYISO report, it provides a concise, readable introduction to the issues addressed at more length in the technical studies.  In addition, the NYISO report includes an extensive bibliography.

Not a bad place to start if you are interested in understanding these issues.

RELATED: EPRI and PJM conducted a “PHEV Summit” in January of this year, exploring these same issues.