if you want to improve the electricity grid, you really have to have good, cheap storage.
I'm interested in that point as my personal view has changed. Why do you think cheap storage is needed to
improve the grid? (I think the Grid in the UK is better developed than in the USA [but I don't know that for a fact] so that may be a factor?)
I used to think that PowerWall was needed "now". I've changed my view to storage not being needing at all until the production from renewables exceeds demand (which I think is quite a long way off). Up to that point power companies can turn off other sources when renewable supply is high; we may not be well endowed, currently, with generation equipment which can be turned on-and-off, and Solar and Wind would be wasted if not used, but presumably over the next decade we could concentrate on building fossil fuel generating power that can be run stop/start. Currently when the Number One Soap finishes / goes to an advertising break, and people start boiling kettles, over here in the UK we fire up instant-start power-stations (Gas Turbine I think) to cope with the demand. Presumably similar problem in USA, although time-zone spread may mean that peak power, for evening cooking etc. on winter evenings, may be spread and less dramatic than in UK? We buy power from France etc. (one hour time difference to us) to help with that, but across the time zones of the USA perhaps there is a much better "opportunity"?
I also think that once we have smart metering, and my power company can tell my house to "adjust" its usage, that peak-power requirement will a) be reduced (e.g. my fridge & freezer will turn off for a while) and also b) my car battery's energy can be "sold" back to the grid. So when I get home at, say, 6PM to 10PM I can sell the remaining power from my car battery and from 10PM to 6AM it can re-charge - using cheap rate overnight electricity (currently at least 50% cheaper here in the UK) as excess is produced (currently from always-running generators, but in future increasingly from Wind). Perhaps car batteries are the only/majority? storage requirement we will need, going forwards?
I read somewhere that in June or July last year the solar panels on people's houses produced 99% of the domestic electricity usage at that time. That leaves out all the business usage, plus we have almost zero AirCon in domestic houses in the UK, and no lights on in the house on a summer's day
, and everyone was out at work ... but still! it seemed to be more to me than I would have guessed
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Actually ... in a couple of years time Autonomous vehicles will be here, and I will no longer own a car and just summon an Uber Autonomous Vehicle when I need one, so the fleet size will reduce to match the maximum number of concurrent, shared, journeys and perhaps the opportunity to use car batteries to augment the grid will go away, or diminish. All the Uber vehicles will park up somewhere when demand slopes off in the evening, but their software will have optimised vehicle usage to select a vehicle for a journal to use up battery energy optimally so that it returns to base for recharging "empty". Ergo none available to put back into the grid.
There again, I suppose that that software model could easily be changed if the price of selling back to the grid was higher than the, subsequent, cost to recharge. no Uber vehicles to be found at 8PM because they've all found somewhere to plug in and SELL their battery contents to the grid at a better price than Punters are paying for a ride!