We have this in CA. I have Tesla batteries and they promote wanting me to enroll my batteries into a larger grid so their capacity can be used during higher load events.
I thought it was a novel idea when I heard about it.
I love this. It’s basically an edge cache for power, with an enormous amount of side benefits - smooths out solar power, smooths out the duck curve, and allows the grid to size closer to the average load and absorb the spikes at the edge, instead of cascading into the core.
There was an article earlier about the distribution challenges that come from large workload fluxes, too - tl;dr is the transmission lines get less efficient under higher load, so smoothing out the demand curve to the end user also raises the efficiency of the entire grid.
And as someone points out below - the proliferation of EVs also helps this, because they can act as a “deep” reservoir so the local residential batteries can be much smaller - more buffers than something expected to run the house for more than a couple hours, so that makes the whole setup even cheaper, depending on when and where the EVs are getting charged.
I live just over the border in Massachusetts and we have something similar, called ConnectedSolutions. It is essentially the same kind of program except that the benefit is a 0% loan on the battery purchase. I have a 15kW battery that allows me to power the entire house overnight without drawing from the grid. When the power company wants to draw from my battery, they send me a notification through my battery’s app. I can opt out some fixed number of times, too. And, just as when my solar runs net negative, the power company pays me (in bill credits) whenever the virtual power plant draws power.
> I always wonder what happens when these things catch fire
If you're hoping someone will chime in to tell you they have magic firefighting foam inside them or something, I regret to inform you that what happens if it catches fire is exactly what one might naively expect from large lithium batteries.
As a consumer, would you want the extra usage on your battery? Those extra cycles have to cause some additional degradation to the system, but I do not know how much.
> As a consumer, would you want the extra usage on your battery?
I feel like this is likely going to be a non-issue in practice. Because these batteries are rated to last at least 10 years either way. And by that time, the cost of replacement will be dramatically cheaper.
Net metering rates are pretty poor, so I would guess not much outside of extreme grid instability. Although, you then might want to selfishly hoard the juice for yourself.
I thought it was a novel idea when I heard about it.
There was an article earlier about the distribution challenges that come from large workload fluxes, too - tl;dr is the transmission lines get less efficient under higher load, so smoothing out the demand curve to the end user also raises the efficiency of the entire grid.
And as someone points out below - the proliferation of EVs also helps this, because they can act as a “deep” reservoir so the local residential batteries can be much smaller - more buffers than something expected to run the house for more than a couple hours, so that makes the whole setup even cheaper, depending on when and where the EVs are getting charged.
Distributed power storage/generation has been a thing for a century and it’s finally economical enough to be mainstream.
This was the whole pitch of the solarcity/tesla solar tiles + power wall a decade or more ago.
also
Titanic Sinks Four Hours After Hitting Iceberg
If you're hoping someone will chime in to tell you they have magic firefighting foam inside them or something, I regret to inform you that what happens if it catches fire is exactly what one might naively expect from large lithium batteries.
I feel like this is likely going to be a non-issue in practice. Because these batteries are rated to last at least 10 years either way. And by that time, the cost of replacement will be dramatically cheaper.
But given they are NMC chemistry, you probably wouldn't want to cycle them a lot for the grid (or just your home).