I would think that just charging $2/kWh during peak time would be enough to bring down peak load without using any batteries.
So they're being paid not just for not using this power at that moment, but being part of a system of "demand response" that lets the grid plan ahead and modulate demand.
They also do this with people's AC and various large industrial energy users.
But, time-of-use rates are a currently underutilized idea, and with greater computerisation, you can get more and more value from this on short-timescales.
You want to start with the low hanging fruit first, and EV chargers are that easy win as they are being installed now.
Is it not normal in the US to pay less for electricity at night and on weekends?
That's very common in the places (Netherlands and Switzerland) where I've lived, for as long as I can remember, and seems much more low-tech than using consumer batteries to supply back to the grid and paying them a custom rate.
https://www.utilitydive.com/news/an-emerging-push-for-time-o...
> A new idea is to vary the price of kWhs, making the price higher for residential customers during peak demand, and lower at other times, allowing for more precisely pricing kWhs at what they cost.
> With today's flat per-kWh rates, "customers who use the grid more during peak demand are underpaying for the costs of meeting that demand," Brattle Group Principal Ahmad Faruqui told Utility Dive. "Customers who use the same kWhs during off-peak times pay the same bill and are subsidizing the others. TOU rates can redress that inequity."
I will assent to these powerful features when there is a strong legal guarantee that it will be used to improve the world, not to juice up someone's q2 numbers by charging me more.
Remember that these are the same companies that by and large lobby against being able to sell solar power back to the grid.
Worse, they lobby against residential solar as a whole. I could install enough solar panels & batteries to cover 100% of my needs through the year, but unless I disconnect from the grid completely, I'd still pay about half of my current electric bill, without using any electricity from the grid. The utility company with local monopoly is specifically making sure as little residential electric is installed as possible.
It sounds fancy and pro-consumer, but in reality, we have some of the worst rates in the nation. Jon Oliver even did a recent bit about how ridiculous it is. (Search for "Jon Oliver SDG&E".)
$2/kWh is very expensive. I guess by paying the powerwall users you can limit how much you spend with them. Not sure with how much local granularity can you turn them on, but it definitely helps
Also, I imagine this is to get the power wall users 'hooked'. Then over next few years that $2 will turn into 20 cents.
Will the price go down in the future? Maybe. Is this a gimmick to get people hooked? Probably not, assuming Tesla isn’t paying end users more than they make to join in.