A Tesla subsidiary registered as Gambit Energy Storage LLC is quietly building a more than 100 megawatt energy storage project in Angleton, Texas, a town roughly 40 miles south of Houston. A battery that size could power about 20,000 homes on a hot summer day. Workers at the site kept equipment under cover and discouraged onlookers, but a Tesla logo could be seen on a worker’s hard hat and public documents helped confirm the company’s role.

I'll predict success if Elon Musk is behind it. I had always been skeptical about Musk in the past years but what he has done with SpaceX is absolutely brilliant.

A mega pack sized battery to support our grid.

Tesla Is Plugging a Secret Mega-Battery Into the Texas Grid

https://www.bloomberg.com/news/feat...-secret-mega-battery-into-the-texas-grid

He'll be able to pay $25 per megaWatt/hr to charge it up, then sell that same electricity back into the grid at $1250 to $9000 per megaWatt/hr during shortages - per current ERCOT/TxPUC rules.

2020 was the first full year that Tesla Energy and Storage generated sales from its industrial scale megapack battery. Without more detailed disclosure, it’s going to be difficult to tell the degree to which the product is carrying or being carried by the residential storage and solar businesses. Such a condition contributes to the efficiency of the message, keeping the story centered on whichever division is experiencing the most success at any given moment, and how it might contribute to a bold clean-energy future, rather than getting bogged down in details like whether or not it makes money, or the size of the addressable market.

Chemical batteries aren’t the only available solution for grid-scale energy storage and, given their limited lifespan and potential to catch fire, they might not be the best one, either. Most of the active grid energy storage in the world right now, 97% of it, is comprised of pumped-hydro storage plants. Pumped hydro power storage is accomplished by using excess grid energy to pump water from a reservoir up into a higher reservoir, then using gravity to run it back into the lower reservoir through a turbine when the energy is needed. Pumped hydro projects are literally ten times larger than chemical grid battery arrays, on average, and run on gravity and water, which don’t wear out the way cells do.

Someone help me with what I am missing:

100 megawatts is 100,000 kW.
100,000 kWH of storage capacity / 20,000 homes = 5 kWH available per home.

So, about 30 to 60 minutes per home.