In brief: Elon Musk's latest secret project is a large grid battery in Texas designed to increase its electrical grid stability. And while it's not the first nor the only grid storage system Tesla has ever built, this could be a boon for the company's ambition to become a decentralized electric utility.

Tesla's energy business grew 200 percent year-over-year in Q4 2020, and the company deployed a whopping 1,584 MWh of energy storage over those three months. Elon Musk's dream is to see Tesla Energy become a distributed global utility that will eventually outgrow the automotive business. To that end, the company has pushed hard for the adoption of its Powerpack and Megapack installations.

Slammed by several electrical outages last month by a record-breaking hard freeze, millions of Texans experienced one of the disadvantages of the state's independent electrical grid. The winter storm exemplified the need to connect to other US electrical grids and reform grid management practices in preparation for future extreme weather events.

According to a Bloomberg report, Tesla created a subsidiary registered as Gambit Energy Storage LLC to silently build a 100-megawatt energy storage system in Angleton, Texas. It's essentially a large battery array designed to power 20,000 homes on a hot summer day. The Electric Reliability Council of Texas (ERCOT) is evaluating a proposal to start commercial operation by June.

For years, Musk has been interested in expanding into residential energy storage. In 2015, he proudly announced the Powerwall, a home battery system that has yet to make a real dent in the market despite being available for years in select Tesla-branded Home Depot selling spaces. While the Gambit project is not the first grid energy storage system built by Tesla, it shows its commitment to the energy business just as much as it is to the electric vehicle business.

In 2017, Tesla unveiled a 100-megawatt grid storage system built in South Australia to store the surplus electricity generated by a wind farm. The company's Powerpack and Megapack systems for utility storage have been in use for years near substations and in small towns, saving millions of dollars in the process. Those are relatively small systems, but Tesla and PG&E are currently building a 182.5-megawatt system at an electric substation in the San Francisco Bay Area, which could become operational by the end of this summer.

Image credit: Bloomberg