Ann: Chairman's Address to Shareholders, page-33

I know my motivations are not the only valid ones, but I think mass adoption by domestic consumers will need it to make economic sense first. That begins to happen around $1500 for me. Environmentally, it’s actually better to feed into the grid, offsetting carbon production at the time of production, than it is to lose the round-trip-efficiency losses in a battery, so there’s no motivation for me there. I have other uses for the money I’d be wasting than using it to thumb my nose at the government - for example donating it to an environmental charity gets your message across better, is tax deductible, and I’m sure they’d be able to use $5k quite effectively.  

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