sierraclub.org - sierra magazine - may/june 2009 - innovate
Innovate | For Plugged-In Living
By Myron Levin
When an ice storm doused the lights in Harvard, Massachusetts, John Sweeney (left) didn't wait for help from utility crews. During the four-day outage, he transformed the battery of his hybrid Toyota Prius into an emergency generator to power his home.
Sweeney hooked up an inverter to convert the direct current (DC) from the Prius battery to the alternating current (AC) used by homes. About every half hour, the gas engine switched on for roughly five minutes to recharge the battery. Over four days, Sweeney used 17 kilowatt-hours of electricity, and the Prius burned about five gallons of gas. (Sweeney figures a nonhybrid vehicle, idling constantly, would have consumed about 80 gallons of gas.)
A 50-year-old electrical engineer, Sweeney has long been obsessed with efficient energy use. His interest goes back to the 1970s gas crisis, when he designed a hybrid vehicle for a college project. Sweeney and his wife, Mary, live part-time on a sailboat, running the microwave and other devices with wind turbines and batteries. At home, smart meters gauge the power use of appliances, enabling the Sweeneys to cut their electric bill by $50 per month. Wiring the Prius was not too difficult, Sweeney says, but that's an electrical engineer speaking.
Sweeney's friends were skeptical when he bought the Prius, but for him the choice was simple. It was whether to give his money to "somebody who's going to change the way of doing things or to the oil companies." Thanks to his backup generator with floor mats, some of those friends have now seen the light.
Infographic: Funnel Inc.; photo: Lisa Aciukewicz