http://techcrunch.com/2015/04/30/tesla-powerwall-home-battery/#.rbnqyk:wN2u I would love to see this work.
Yep. I looked at solar panels for my house, but the position of my roof is such that not enough panels could be installed for savings over time to cover the cost. I'll look at it again as the prices go down. As for the battery, I'm not sold on it yet because in theory, excess electricity produced by a home solar plant is sold to the grid. That's a feature of the economic analysis, and one that people won't want to renounce.
Yeah but you sell at wholesale rates and buy at retail. Better to store it, depending on the cost of storage, and use it yourself. You could probably program it to sell any excess you can't store. The other interesting use would be as a power backup, and to arbitrage rates, i.e. charge at off-peak low rates and discharge (use) when rates are higher (if the power companies offer this plan) or even sell it back to the power company when rates are higher (I doubt this would be profitable). I haven't read enough to know how many KWhours storage you get for what cost. I'm sure it's spendy.
I'd be curious about this, my house is south facing with nothing but the odd tree blocking the view, so if I can have solar panels (there's a covenant on the building as I live in a Ye Olde Bit of Merrie Englande and they'd like to keep it that way) this could be of use when the subsidy dies off for selling the leccy back to the grid. There's also storage capacity and life cycle of the battery, if you're going to empty the battery overnight and charge it during the day its efficiency will drop off quicker than one with a partial charge/discharge iirc, and we've new battery tech on the horizon, so it could be quite expensive to get one that'll be superseded 2 years later.
Here are more details from a US viewpoint. wapo article I'm guessing with inverter and associated wiring/controls installed it's about $7,000 USD (not including the cost of any solar panels). It would have 10KWh storage which is about 1/3 the average us consumer's daily use (yeah we're pigs). Where it might be interesting is not to store solar energy but as a power backup. People here spend that much or more on natural-gas powered electrical generators. With conservation during a power outage (ice storm or hurricane) it might last 5 days running the fridge and some lights. If you mitigated the cost with solar (don't know over how long it would take to recover costs, probably too long) it might be more interesting. The storage capacity degrades with time. It's the same tech used in his cars and other electric or hybrid cars. I think after 10 years it would have 50% capacity.
I've never heard of a generator that runs on natural gas. I grew up in the country, so we didn't have that newfangled pipeline stuff.
Oh, and for a point of comparison, we have a 960 ft^2 house (including the basement it's double) and use a max of ~600 kwh per month now that we ditched the electric furnace.
