By IANS,
Washington : Plug-in hybrid electric vehicles could help reduce greenhouse gas emissions that fuel global warming, but the benefits are highly dependent on how the power system changes in future.
“Plug-in hybrids represent an opportunity to reduce oil consumption, leverage next-generation bio-fuels and reduce greenhouse gas emissions.”
The types of power plants installed in the next two decades will not only affect how much we can reduce emissions from electricity, but also from vehicles if we plan on plug-in hybrids playing a substantial role,” said Constantine Samaras of Carnegie Mellon’s departments of Engineering and Public Policy (EPP) and Civil and Environmental Engineering (CEE).
“We are finding that even when the impact from producing batteries are included, plug-in hybrids still produce slightly less greenhouse gases than hybrids that run only on gasoline. But plug-in hybrids could cut emissions in half if they are charged with electricity from low-carbon sources,” said Kyle Meisterling of EPP and co-author of the study.
Already, automakers have discussed plans to develop plug-in hybrids and California recently ruled that the auto industry must sell nearly 60,000 plug-ins statewide by 2014.
With the price of gas heading beyond $4 per gallon, interest in alternative vehicles continues to grow. Samaras and Meisterling also say plug-ins may allow greater use of the limited supply of bio-fuels because they use a lot less gasoline than regular cars.
The researchers found that life cycle greenhouse gas emissions from plug-in hybrids are about one-third less than a traditional gasoline-powered car. They also argue that with coal-fired electricity, emissions from plug-in hybrids are still lower than traditional cars, but are higher than ordinary hybrids.
The study was published in Environmental Science and Technology.