Poll: Should EV Charging Stations Bill by the Hour or kWh?

The CSMonitor has an article about what is considered "fair" to charge to electric car drivers when they recharge their batteries at commercial charging station. I would have thought that the obvious solution would be to bill by kWh with a reasonable premium above local electricity rates to provide an incentive and pay back the equipment, but apparently some prefer to charge by the hour, like for example $2/hour or $1/hour.

This has the benefit of being simpler to understand than kWh-based prices, but it doesn't seem fair since electricity costs vary by location and even by time of day in certain places, and different electric vehicles will draw different amounts of electricity per hour.

So I'm curious to know what you, dear reader, think. Would you rather see charging stations charge by the kWh or by the hour? Or maybe something else (please explain in the comments)?

Of course, I'm sure we'll also see many business provide free electricity in their parking lots to attract customers (as a kind of loss leader). If that becomes widespread enough, it might be possible for many electric car drivers to get a good portion of their electricity for free!

Via CS Monitor, ABG

See also: Ford C-MAX Energi Plug-in Hybrid to be Priced at $30k After Tax Credit

Poll: Should EV Charging Stations Bill by the Hour or kWh?
The industry is still trying to figure it out...

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