There is no shortage of ideas as to how consumers will recharge electric vehicles, andMotor Co. has been closely monitoring all potential options, says Nancy Gioia, director of hybrid-electric vehicle programs.
Charging EVs and plug-in hybrid-electric vehicles via a household outlet or employing a battery-swap technique, in which owners trade in depleted batteries for fully charged units, are two of the leading ideas among auto makers, utility companies and suppliers involved in the burgeoning electric-vehicle industry.
Gioia says battery swapping is an “interesting” concept, but there are potential pitfalls that must be overcome.
“A lot of EVs, because of the size of batteries and energy density, may have liquid cooling, and that (cooling) loop has to break to change (a battery). It’s a difficult thing to do,” she tells Ward’s.
Battery swapping also is impractical because of the logistics involved. Under most scenarios put forth by proponents, a consumer would have to drive to a location similar to the neighborhood oil-change store, where they would trade in their old batteries.
However, many auto makers likely will use their own unique battery packs, making it difficult for a battery-swap outlet to keep the correct batteries in stock, Gioia says. Additionally, battery packs are expected to change year to year as technology improves.
also is studying the fast-charging concept, in which EV drivers would plug in at stations operated by municipalities or privately owned companies recharging in a fraction of the time it would take using a household outlet.
Gioia says fast charging may be possible in the future, but there are pitfalls associated with the procedure currently being proposed. Fast charging “drives additional hardware requirements into the vehicle because of the high current flow. That means we have to beef up some components in the vehicle, which would add costs.”
Ford is looking at battery charging in three phases. Level one would be through a typical 110-volt outlet, level two would utilize a 220-volt power source and level three would be fast-charging.
Gioia says not only would fast-charging drive up the cost of EVs and PHEVs, it also would cost far more to construct the necessary stations, compared with the cost of household charging.
Most home-charging setups would require 1.5 kW-3.5 kW in power and cost $500-$1,200 for a 220-volt outlet to be installed. In comparison, a fast-charging unit would require 50 kW of electricity at a cost of $50,000.
Additionally, early generation battery-cell technology may not be able to handle the rigors of fast charging. “We want to make sure any type of fast-charge doesn’t degrade the life or performance of cells,” Gioia says, noting the technology probably won’t be viable until at least second-generation EVs hit the road.
Ford, which next year plans to launch a battery-electric version of its Transit Connect small commercial van, followed by the 2011 production launch of the Focus EV and a PHEV in 2012, has developed its own recharging system designed to “talk” with the nation’s electric grid.
Developed in conjunction with 10 utility companies, two research firms and the U.S. Department of Energy, the system will be installed on Ford’s test fleet of plug-in hybrid Escape cross-utility vehicles.
The technology allows the vehicle operator to program when to recharge the vehicle, the length of the charge and the utility rate. For example, an operator could choose to charge only during off-peak hours, when electricity is cheaper, or when the grid is using renewable energy.
The system would interact with so-called “smart meters,” which are being installed by utility companies across the world, Gioia says. Southern California, alone, is expected to have 5.2 million smart meters in place by 2010.
Utilities are “moving toward smart meters in the house or office building to help control energy flow more intelligently,” she says, adding meters can be programmed to tell consumers when it’s most economical to run a major appliance such as a dishwasher or dryer.
“You program smart meters for when you want to (use energy), and it gives warnings if you’re going to run at a higher rate.”
Smart meters also will allow for a greater proliferation of electrified vehicles in the future. Currently, the nation’s electric grid is insufficient to handle large numbers.
“With every PHEV or EV, when you’re plugged in, it’s equal to about the whole (electric) load of a house,” Gioia says. “So if you had a street with 10 houses and five of those households had plug-ins, all of a sudden it’s equal to 15 houses. We recognized the need for load leveling and the opportunity to adjust when to recharge.”
Owners of Ford vehicles could communicate with smart meters wirelessly via an in-vehicle touch-screen-navigation interface.
“We found through this project that it ultimately ends up being a low-cost solution,” says Gioia. “Other solutions that allow (this type of) interface are being developed, and some exist but require a subscription or other data-based interface.
“So if a customer has the hardware in their car and wirelessly connects with no fee, it’s the lowest-cost solution. That’s what we developed and demonstrated. It’s all about putting the control of energy in the customer’s hand.”
The technology now is being perfected, but Ford has yet to announce a rollout date or pricing for the system. The auto maker would be open to licensing the technology to other auto makers but presently has no plans in place to do so.
“We’re defining protocol communication in terms of how we use it, and that will be unique to us,” Gioia says.
“But we want an open architecture. We can’t have unique architectures for Ford cars and other cars. If someone wanted to license it, we would consider it. But the key is (whether) they can write their own (software) with an open protocol.”