CFE agenda 011215 - Laserfiche WebLink

Browse Search

Coal - fueled electric cars sully air, too t Road Worrier Bruce Siceloff' A new' study finds that plug -in electric cars can be the dirtiest vehicles on the road — when they run on elec- tricity produced from the fa- vorite fuel of America's util- ities: coal. Nissan Leafs, Teslas and other electric cars have no tailpipes and no exhaust. But three University of Minneso- ta researchers looked at ,air pollution from the entire life cycles of plug-ins and other alternative cars. Their calculations includ- ed the pollutants produced when corn is grown and fer- mented for ethanol and when minerals are mined to make the big lithium -ion bat- teries that power plug -in cars. And for plug -in cars, they did the math on electric- ity derived from burning coal and from cleaner sources such as natural gas, wind and solar. The study, online at bit..ly /1xLuhDf, was pub- lished in December in the Proceedings of the National Academy of Sciences. It measured each car's produc- tion of ground ozone and fine particulate matter — two, unhealthy elements of air pollution, which kills more than 100,000 people in the SEE SICELOFF, PAGE 8A' SICELOFF CONTINUED FROM PAGE IA United States each year. The conventional gas car ranked in the middle of the pack when it was compared with 10 alternatives. Electric cars were the cleanest if they ran on electricity derived from renewable sources or natural gas. The dirtiest cars relied on coal -fired electricity or on ethanol. "If we adopt electric vehi- cles and power them with clean fuel sources, it can cause a large decrease in air pollution," the lead author, Christopher W. Tessum of the University of Minneso- ta's Engineering Depart- ment, said Monday. "If we power them with a dirty source, coal, it causes an in- crease in air pollution." For every 100 air pollution deaths attributable to gaso- line cars, Tessum and his col- leagues calculate the equiva- lent of only 26 deaths from plug -in cars, driven the same number of miles, that use electricity created from wind or solar power. Burning natural gas to make:that same electricity is almost as clean (50 deaths) - and, it turns out, much clean- er than burning compressed natural gas in the cars them- selves (89 deaths). The dirtiest cars The dirtiest picture was painted for plug -in cars with electricity produced entirely from coal — at 363 deaths on this scale, nearly four times deadlier than the average gaso- line car. This exaggerates the true picture, since coal is used to produce less than half the nation's electric power. Tessum and his colleagues reckon that 45 percent of our electricity will come from coal in the year 2020 - he points out that some projec- tions are lower and at that share they attribute 186 deaths'to these cars. As old power plants are de- commissioned, coal is be- 'coming a smaller part of the electric power supply. Duke Energy says coal is its top fuel source for North and South Carolina customers, currently a 31 percent share. Duke projects that coal will fall by 2029 to third place be- hind nuclear, and natural gas, accounting by then for 21 percent of its electricity. "If you look at the energy mix in North Carolina, there's also a lot of nuclear, which is carbon- free," said Duke spokesman Randy Wheeless. Gas- electric hybrid cars tir The News & Observer+ `If we encourage electric vehicles with clean electricity the gains are much higher.' CHRISTOPHER W. TESSUM UNIVERSITY OF MINNESOTA such as the standard Toyota Prius — the kind that don't plug into the electric power grid show up pretty well in the Min- . nesota study, with an estimat- ed 71 pollution- related deaths for every 100 deaths from gaso- line cars. Since consumers have more direct control over what car they buy than over the fuel source used to produce local electricity, the Minnesota study suggests that buying a thrifty hybrid car might be a good idea. , "Consumers, if they're con- cerned about the health im- pacts that come with pollution — things like asthma, heart dis- ease and the increased proba- bility of death - they can buy more efficient gasoline cars like the Prius," Tessum said. `But there's a ceiling for how efficient these' cars can be. If we encourage electric vehicles with clean electricity genera- tion, the gains are much high- er.,, Other studies have faulted . electric cars for substantial environmental damage, based on high levels of pollu- tion created in the manufac- ture of batteries that car own- ers recharge at their homes at night. Tessum said the Min- nesota study calculates much lower pollution levels from battery production. Siceloff: 919- 829 -4527 bruce.siceloffp newsobservercom or newsobserver.com /roadworrier Twitter: @Road_Worrier