SP: English Study Group

source: http://www.economist.com/sciencetechnology/displayStory.cfm?story_id=15434416

How will we recharge all the electric cars?

Jan 29th 2010 | From The Economist online

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

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

That would be a problem. Unlike the Prius and its ilk—which usetheir petrol engines, along with energy recovered from braking, torecharge their batteries while motoring—plug-in hybrids and pureelectrics have to be recharged direct from the grid. The popularassumption is that they will be plugged into a wall socket in thegarage 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 notglorified golf-carts, but cleaner and more frugal alternatives totoday’s petrol-powered family cars. When fully charged, the Volt (to becalled the Ampera in Europe) can travel 40 miles (64km) on electricpower, enough for three out of four commuters in America to get to workand back without needing to burn a single drop of fuel. Beyond thatrange, a 1.4-litre engine kicks in to generate electricity andsimultaneously propel the car and recharge its batteries.

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

One thing the new plug-ins and pure electrics have in common is abeefy lithium-ion battery pack that needs a lot of heavy charging. Atthe very least, that involves installing 220-volt wiring in the home.Trying to recharge a modern electric car with a standard American110-volt supply takes too long to be practical (up to 18 hours in thecase of the Leaf).

Of course, if not fully charged at night it may have to be rechargedduring the day—when electricity rates can be up to five times moreexpensive. Average peak rates in America are 33 cents a kilowatt-hourcompared with seven cents off-peak. Charging at the peak rate isequivalent 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 chargingtotally destroys any economic advantage an electric car may have.

At least the electricity companies ought to be pleased at theprospect of selling more power, day or night. In theory, rechargingelectric vehicles during off-peak hours should help utilities “fill thevalley”—the trough in electricity demand between midnight and six inthe morning, and thereby get better utilisation from their coal- orgas-fired generating stations. But, again, things are not quite as theyseem. No utility wants to run its network flat out. Schedulingmaintenance becomes difficult, which can lead to more frequentfailures. The net result is that additional capacity has to beinstalled at a cost that would not otherwise be justified.

A study done a few years ago by the Pacific Northwest National Laboratoryin Richland, Washington, suggested there was enough idle generatingcapacity in America to recharge three quarters of the country’s 230mcars if they were plug-ins of one sort of another—provided they onlyconnected to the grid during off-peak hours, and preferably in thecoal-rich midwest. But the vast majority of new plug-ins will belocated in a handful of urban centres on the east and west coasts,which, unlike the midwest, do not have huge reserves of cheap,coal-fired generating capacity. Nor can they import it easily from themiddle of the country, given the fragile nature of the grid.

Southern California Edison has been operating a fleet of 300electric vehicles to find out how customers will use and recharge them.Above all, it wants to make sure that a conversion to electric motoringgoes smoothly, unlike a previous attempt in the mid-1990s. Back then,California thought electric cars like the Honda EV+ and the GeneralMotors EV1 were the wave of the future, and thousands of publiccharging points were hurriedly installed in shopping centres, librariesand airports. But the enthusiasm collapsed when the motor industrysuccessfully lobbied the California Air Resources Board in 2001 to getit to relax a mandate requiring 10% of new cars sold in the state to beemission-free by 2003. With no need to worry about zero-emissionvehicles any more, GM and Honda promptly called in all their leasedelectric cars and crushed them.

This time the Californian utilities are being more circumspect. Theyare concerned about highly concentrated pockets of ownership and theeffects of everyone deciding to recharge their electric vehicles atonce—as they inevitably will do when they return home from work. Thelocal electricity system could be easily overwhelmed, and wider swathesof the grid brought to its knees in the process. Preparing for thismeans beefing up local transformers as well as installing heavy-dutywiring and smart meters in homes to provide early warning of networktroubles ahead. Sooner or later, those additional costs will have to bepassed on to customers.

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

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

Q1: How do you think about electric cars?

Q2: We know that the price of electric cars are more expensive than normal cars. However, if you have enough money, which kind of cars would you choose?