Starting a venture-funded company is hard. Starting a venture-funded car company is probably a lot harder, as Tesla, Fisker, and Coda have likely found out.

But one area that may make sense for venture funding is the electric-vehicle charging station business. A number of companies, including Coulomb Technologies, have entered the space backed by Silicon Valley venture capitalists, and more are on the way.

A new entrant is GridBot, which unveiled its prototype charging station at last week's GreenBeat 2010 conference as part of the GreenBeat startup competition. Electric cars and their impact on the electric grid were discussed at length there.

GridBot married a deceptively simple concept--that of the parking meter--to a recharging station: Users tell the station how long they plan to recharge, which president Richard Donnelly told us at the event no other charger company has included.

That information is transmitted back to the utility or charging-station operator, which allows it to offer the station up for other vehicles to reserve future time slots for charging. Utilization can go up, and drivers are reassured that they can drive close to the limit of their battery pack because they know where and when they'll be able to recharge.

The GridBot also displays real-time electricity rates, which may cause drivers to recharge only as much as they need if power is particularly expensive during peak demand periods.

We did ask Donnelly, about the parking meter analogy: What happens if electric-car drivers "stuff the meter," just as drivers do with cars parked in limited-time parking zones. Did GridBot have a way to prevent drivers returning time and again at the end of their charge to key in another hour or two?

He admitted that they hadn't addressed that issue yet.

GridBot didn't win the startup competition, but it's an encouraging sign of rapid innovation in the field of electric vehicle recharging stations.

[VentureBeat GreenBeat]