The National Academy of Sciences will weigh in on the debate over plug-ins and electric vehicles soon, and the news is not comforting.

The study states that adding batteries to a plug-in will add $5,900 to the cost of a car in 2035, said Daniel Sperling, a professor of civil engineering and the founder of the Institute for Transportation Studies at UC Davis, during a presentation at the Almaden Institute taking place at IBM's Almaden labs.

The batteries in fully electric cars will add $14,400 to the price of a car in 2035, the study states, according to Sperling. The study isn't out yet, he said. It will be released later this summer.

Diesel cars will carry $1,700 to the price of a car. Cars powered by hydrogen fuel cells, meanwhile, will have an additional cost of $5,300.

Regular gas cars, meanwhile, will cost about the same as they do today. A car that costs $19,600 today will cost $21,600 in 2035.

I'll have some more on Sperling's talk in a bit. He's a supporter of electric cars. "Almost everyone agrees that electric drive trains are the future," he said.

Still, the price remains a major impediment. Electricity also will have to come from cleaner sources for these cars to help keep atmospheric carbon dioxide at the 450 parts per million level in the future. Charging a car in a coal state doesn't really cut emissions. Sperling is also the somewhat rare supporter of continued research in hydrogen – it might work, after all.

Costs aside, research and policy directives need to be implemented to de-carbonize the transportation sector. Left to their own devices, oil companies will put their research and development dollars into synthetic fuels like coal-to-liquid. If you count unconventional fuels like tar sands, "there is almost unlimited fossil fuels for under $100 a barrel," he said.

"Unless we have policy intervention, that is what we will go back to," Sperling added. "The oil companies, left alone, will invest in unconventional oils."

Image of Daniel Sperling courtesy UC Davis.

Tags: almaden institute, batteries, electric vehicles, evs, ibm, national academy of sciences, oil, oil companies, plug-ins, transportation