How will we recharge all the electric cars ?  

The Economist has an overly-negative look at the issues involved in recharging electric cars in the US - How will we recharge all the electric cars?.

IN THE ten years since hybrid electric vehicles first hit the highways and byways of America, they have come to represent 2.5% of new car sales. Yet, in places like Los Angeles, the San Francisco Bay Area and Washington, DC, every other car seems to be a Toyota Prius. That is because hybrids like the Prius have sold overwhelmingly where well-heeled early adopters reside.

Expect the new generation of “Post-Prius” electrics—plug-in hybrids like the Chevrolet Volt from General Motors and those relying only on a battery such as the Nissan Leaf—to end up nosing around the same upscale neighbourhoods. With more than a dozen plug-in and pure-electric models arriving in showrooms over the next year or so, sales are expected to outstrip even those enjoyed by the Prius and other hybrids in their early days. A couple of million of the new electric vehicles could be bought by early adopters during the first few years.

That would be a problem. Unlike the Prius and its ilk—which use their petrol engines, along with energy recovered from braking, to recharge their batteries while motoring—plug-in hybrids and pure electrics have to be recharged direct from the grid. The popular assumption is that they will be plugged into a wall socket in the garage late at night, taking advantage of cheap off-peak power. Unfortunately, things are not that simple.

For a start, the new generation of electric vehicles are not glorified golf-carts, but cleaner and more frugal alternatives to today’s petrol-powered family cars. When fully charged, the Volt (to be called the Ampera in Europe) can travel 40 miles (64km) on electric power, enough for three out of four commuters in America to get to work and back without needing to burn a single drop of fuel. Beyond that range, a 1.4-litre engine kicks in to generate electricity and simultaneously propel the car and recharge its batteries.

The medium-sized hatchback Leaf can carry five adults 100 miles on a single charge. To go farther, Nissan has put its faith in a network of rapid-charging stations it is developing with partners. The Leaf is expected to cost $25,000-30,000, about the same as a comparable diesel-powered car. But the battery pack will have to be leased separately (for around $150 a month).

One thing the new plug-ins and pure electrics have in common is a beefy lithium-ion battery pack that needs a lot of heavy charging. At the very least, that involves installing 220-volt wiring in the home. Trying to recharge a modern electric car with a standard American 110-volt supply takes too long to be practical (up to 18 hours in the case of the Leaf).

Of course, if not fully charged at night it may have to be recharged during the day—when electricity rates can be up to five times more expensive. Average peak rates in America are 33 cents a kilowatt-hour compared with seven cents off-peak. Charging at the peak rate is equivalent to buying petrol at $3.63 a gallon (80 cents a litre), instead of 77 cents a gallon off-peak, reckons Southern California Edison, a utility based in the Los Angeles area. In America, peak-rate charging totally destroys any economic advantage an electric car may have. ...

Much, of course, will depend on how quickly the new plug-ins and pure electrics become part of mainstream motoring. Generally speaking, it takes 15-20 years for a new technology to capture 10% of an established market, and a further 10-15 years for it to own 90%. That was the case when steam ships replaced clippers in the mid-19th century, and when petrol-engined taxis took over from horse-drawn cabs in the early 20th century. The same sort of lag occurred with the introduction in the 1970s of emission controls on cars. It takes years for the benefits of volume production to work their way through to the market, and for the supply chain to catch up.

If plug-in electrics follow a similar demand curve to other disruptive technologies, there could be 25m of them humming quietly around by 2025, and ten times that number by 2040. Hopefully, by then, the utilities will have learned to cope with recharging them.

Toyota announced on Monday plans to begin selling “several tens of thousands” of plug-in versions of its popular Prius hybrid in 2012 2011, as Hiroko Tabuchi reports.

In another article in The New York Times today, Matthew L. Wald describes how the rollout of so-called smart meters – which are promoted by electric utilities as a way to save ratepayers money over the long term because they allow for variable electricity rates – is meeting resistance from skeptical consumers, who do not appreciate the meters’ up-front price tag.

In many ways, these articles are about pieces of the same thing — the “smart grid” envisioned for the future.

These two new technologies, plug-in cars and smart meters, are both critical components of the smart grid. In the future, large numbers of automobiles are expected to run on electricity and recharge from a home outlet during the night. (That is true not just of the plug-in Prius, but also of other electric vehicles in the pipeline, like the Chevrolet Volt.)

Smart meters are expected to help encourage consumers to charge their cars at night, because they allow utilities to offer lower rates for electricity at off-peak times. Far less electricity is used at night, when most people are sleeping, than during the day, so power plants have spare capacity to charge automobiles. However, under the current system, there is little incentive to charge automobiles at night because most utilities charge consumers a single rate that stays the same, daytime or nighttime.