Juneau residents might soon see emission-free electric automobiles whirring along the eight miles of highway that connect the state capital's downtown area to the Mendenhall Valley where many Juneau residents live.
At least, that's the vision of Juneau electric utility Alaska Electric Light & Power.
With a small, isolated road infrastructure and all electricity coming from hydropower, Juneau is particularly well-suited for electric vehicle use, Tim McLeod, chief executive of the electric company, said at the recent Business of Clean Energy in Alaska Conference. In fact, a 20- to 30-mile range would probably be adequate for most battery-powered cars used in and around the capital, he said.
"Most of the travel is from valley to town and from town to valley," McLeod said. And, with a relatively mild climate, low temperatures should not unduly hurt battery duration, he said.
McLeod envisions a future in which U.S. electric lighting loads could drop by about 70 percent, presumably because of improved electric light technologies, while perhaps 75 percent of road vehicles run on electricity.
"From my perspective it's not just an environmental issue. It's also to preserve the wellbeing of my community," McLeod said.
"The power sector has substantial spare capacity," McLeod said. "If we charge vehicles off peak, then we can take advantage of the surplus capacity of the infrastructure."
In Juneau, McLeod thinks that the power infrastructure could easily be adapted to support widespread electric vehicle use. With about 32,000 people and assuming 80 percent of the population drives an average of 10,000 miles per year, Juneau residents in total probably drive about 250 million miles per year. A typical electric car power consumes 4 miles per kilowatt hour. That translates to a power demand of about 64 million kilowatt hours, a demand that could easily be met from some modest additional hydropower capacity, McLeod said.
Further, he said, the cost per mile of power for electric cars in Juneau likely could come in at about one-quarter the cost per mile of oil-based fuels. This would clock up an annual fuel savings of about $830 for a typical Juneau resident, McLeod said.
That cost saving would, however, have to be offset against the relatively high cost of buying an electric car.
AEL&P is developing an electrical power rate for a small trial of the Juneau electric car concept, to research the cost of the power supply service and determine whether that cost is acceptable to utility customers, McLeod said.
"We want an experimental electric vehicle rate to try to promote the use of a certain number of vehicles," he said. "We're thinking that the experimental rate will only be for 20 vehicles to start with."
The utility will apply an off-peak rate for vehicle charging, with each customer having a special vehicle-charging meter circuit.
"We think that the off-peak rate would be around 6 cents per kilowatt hour and we would make about a $500 contribution to the separate meter circuit," McLeod said, adding that the $500 contribution would avoid discouraging people from signing up because of the meter cost.
Each customer would fill in an annual survey to provide the utility with information about the number of miles driven, and customers would sign up for five-year service terms.
The public availability of battery charging stations also would encourage electric vehicle use -- the City and Borough of Juneau anticipates putting charging stations in some public parking garages, he said.
However, one potential hindrance to the introduction of electric cars would be a widespread switch from the use of oil to the use of electricity for the heating of buildings in Juneau.
Essentially, the use of electric space heating could crowd out the power supply capacity for cars while also pushing up the cost of electricity, McLeod said.