Scientists calculate future benefits of electric vehicles
22 Nov 2016 by qmwwwtqmqt.d qmwwwtqmqt.d
Electric vehicles that run on batteries instead of hydrogen fuel cells are more likely to be environmentally friendly in the future, according to researchers from California and Munich.
The scientists were looking to understand which mode of transport was most cost effective including the cost of infrastructure for the vehicles. Researchers created a number of scenarios for the town of Los Altos Hills, near Stanford University in California.
Markus Felgenhauer, doctoral candidate at the Technical University of Munich and lead author, said: “We looked at how large-scale adoption of electric vehicles would affect total energy use in a community, for buildings as well as transportation. We found that investing in all-electric battery vehicles is a more economical choice for reducing carbon dioxide emissions, primarily due to their lower cost and significantly higher energy efficiency."
Electric vehicles are found either in the form of plug in cars with rechargeable batteries or fuel cell vehicles that convert hydrogen gas into electricity. Both these cars do not emit carbon when driven.
Neither are completely emissions free as battery vehicles require electricity, which is usually generated from fossil fuels, and hydrogen fuel is derived from natural gas with carbon dioxide as a by-product. Although there is a device called an electrolyzer, that uses solar generated electricity to split water into hydrogen and oxygen, this is both expensive and energy intensive.
Los Altos was chosen as it was “distinguished by an unusually high solar-generation capacity in the county with the highest share of electric vehicles in the state,” said Felgenhauer. The scenarios were imagined 10 to 20 years from now when battery and fuel cells vehicles are expected to be more widely used.
Felgenhauer said: “To be cost competitive, fuel cell vehicles would have to be priced much lower than battery vehicles. However, fuel cell vehicles are likely to be significantly more expensive than battery vehicles for the foreseeable future. Another supposed benefit of hydrogen - storing surplus solar energy - didn't pan out in our analysis either. We found that in 2035, only a small amount of solar hydrogen storage would be used for heating and lighting buildings."
The research was published in Energy.
