Comment Actual data from the FAQ (Score 4, Interesting) 58
From https://www.masscec.com/massce..., they expect to draw 3kW - 10kW for 3 hours, for a total draw of 9 kWh - 30 kWh.
We have a Kona EV with a 65 kWh battery, which we limit to 80% charge to maximize battery life. Their expected draw is 14% - 46% of battery life. With our existing V2L adapter, the Kona can specify the minimum battery level where it will cut off. If we set it to cut off at 60%, then they could have 20% of the battery, but no more. 60% is enough for all our expected driving for a couple days, so I'd be comfortable with that. But also, odds are that the power drain event will be in the evening, and there'll be plenty of time overnight to recharge back to 80%.
Lithium batteries don't like being charged all the way to 100% or drained to 0%, but running them back and forth between 60-80% won't measurably damage them for thousands of cycles.
If the software were better, we'd be able to say, "We want to be back at 80% at 5AM. And in any case, we want to keep at least 60% of our battery for our own needs - driving, V2L for our own house in a power failure, etc. Within those constraints, you're welcome to the rest of the power, but we're selling it at $0.60/kWh. If you *really* want power, we'll go from 60% to 40%, but it'll cost you $1.00/kWh below 60%." And then the grid could decide whether it's willing to pay our price, and how much it wants.