Here Come the EVs
The 2011 Nissan Leaf
And why you’ll want a control system for your new electric car.
The age of the EV—or electric vehicle—has dawned. This could mean big things for your electronic home.
The much-anticipated Chevy Volt and Nissan Leaf EVs have officially launched. The $33,000 Leaf and $41,000 Volt are two of the first all-electric vehicles—or almost all-electric, in the case of the Volt, which uses a gas-powered backup generator. Yes, Tesla has had a $100,000-plus electric sports car for a couple of years, but this is the first time several mass-market automakers have ramped up serious EV offerings.
Ford is reported to have five battery-based vehicles in its pipeline, including battery-electric versions of the Transit Connect van and a new 2011 Focus.
Some new cars will be all-electric EVs, and others will be plug-in hybrid electrics (PHEVs). The plug-in part is how they differ from today’s gas/electric hybrids like the Toyota Prius. And that’s both good news and bad news. Good because you can run the car on an electrical charge and potentially never have to fill up with gas; bad because the electrical charge limits the range of these vehicles.
The Leaf will only take you about 47 to 100 miles on a complete charge, so it’s best used for running local errands and most commutes. GM claims a 25-to-50-mile range for the Volt’s battery range and more than 300 miles with its gas-powered assist. Ranges are expected to increase as electric battery storage technology progresses, but we’re unlikely to see the 400-mile tank of gasoline range from full EVs any time soon.
Charging these cars also takes time. A 110-volt charge from a standard wall outlet could take 12 to 18 hours. Most car companies will offer optional 240-volt chargers, which will require an electrical installation and can do a complete charge in three to five hours.
That’s still a whole lot of time and inconvenience, but there are technologies targeted at minimizing this. Eaton Corp., for example, is producing 500-volt chargers for quickie 15-minute charges at fuel stops, restaurants and other popular stops along the road.
Then there’s Evatran, whose Plugless Power “proximity” charging system charges the vehicle’s batteries wirelessly via a parking block that sits under the nose of the car and gets its juice from a nearby control console. You could have a parking block in your garage, for instance, and just pull up and start charging, no inconvenient cord to get out. If Evatran has its way, you’ll also see these all over public spaces. After all, says Evatran’s Rebecca Hough, who wants to get out and plug in an electrical cord in the rain?
GE, too, has a WattStation designed to complete a full charge in four to eight hours. GE also says its WattStations have smart-grid enabled technologies that could help utilities manage the impact of EVs on the electric grid.
Smart Grid Cars
Electric utilities are eyeing the EV with great concern, and with good reason. A big part of the utilities’ smart grid initiatives is designed to reduce peak power loads that occur when most people use energy, such as from 3 p.m. to 8 p.m. We come home, turn stuff on, and bam, there’s a peak load. Add 240-volt EV chargers in every home—or even some of them—and you’ve got a massive electrical demand.
This is partly why utilities want to institute programs like time-of-use pricing, in which electric rates during peak periods like 3 p.m. to 8 p.m. will be more expensive, and demand response, in which the homeowner voluntarily allows the utility to turn down or shut off appliances like air conditioners and EV chargers to avoid instituting brownouts or having to buy expensive power elsewhere.
A solution to this problem could come in the form of a charging unit equipped with some type of communications technology, such as ZigBee, so it can receive signals from a two-way smart meter, with which homes on the smart grid are being equipped. EVs, too, already come with on-board charging options.
But will this be enough to enable your EV to charge automatically less expensive times? It’s likely that you would also need a processor in your home to manage your charging preferences and that can receive signals from your mobile device so that you can change your charging options. You may also need that processor to make sense of the rate information coming from the utility. All of this will be best facilitated by a home energy management or control system.
This system will keep track of all your home’s energy use, automatically shutting off appliances, devices and electronics that aren’t needed, and keep track of the production from alternative sources of energy such as solar electric panels.
It could also help you move energy around. Smart grid advocates look to technology called V2G, for vehicle to grid. It’s two-way power, meaning your home energy management and control system could at times borrow power from your electric car’s battery to power something in the house, instead of buying expensive power from the utility to do so.
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