After nearly collapsing last month, the previously unrevealed construction of a secret mega-battery connected to an ailing electric grid showed that Tesla founder, Elon Musk, is getting into the epicenter of the United States energy economy.

According to Bloomberg, Musk is silently getting into the Texas power market after the revelation of the gigantic battery, marking the move as Tesla Inc.'s first major foray into the energy market of the U.S. Based on the report, a subsidiary of Tesla registered as Gambit Energy Storage LLC is quietly building a more than 100-megawatt energy storage project in Angleton, Texas, which is a town, estimated 40 miles down south of the city of Houston.

Tesla's Secret Mega-Battery

Moreover, the secret mega-battery could power around 20,000 homes on a hot summer day. On-site workers are keeping the equipment undercover as they discouraged onlookers. However, the Tesla logo could be seen on the workers' hard hats and supported by the public documents that the company is behind the said project.

The property record currently filed with Brazoria County shows that Gambit shares the same address as a Tesla facility close to its auto plant in Fremont, California. A filing with the U.S. Securities and Exchange Commission lists Gambit as a subsidiary of Tesla. But executives from Tesla did not respond to the numerous requests for comment when asked.

However, Tesla's shares gave up early gains on Monday, after falling 6 percent to $562.31 as of 3:17 p.m. in New York. The fall in the past four days totals to around 20 percent so far this year.

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On the other hand, as winter storms pummeled Texas last month, leaving millions of individuals without power for days, Musk tweeted and mocked the Electric Reliability Council of Texas, also known as ERCOT, which is a nonprofit group that manages the flow of the electricity in more than 26 million customers in the area, posting 'Not earning that R.' The 49-year-old Tesla founder and CEO recently moved in the state as his various companies have expanded its operations in Texas, Independent reported.

The secret mega-battery is a battery-storage system built by Gambit, a subsidiary of Tesla, registered with ERCOT and sits adjacent to a Texas-New Mexico Power substation. Senior director of system planning at ERCOT, Warren Lasher, shared that the project has a proposed commercial operation date of June 1. But the duration of the battery remains unclear, while ERCOT could not comment on the project's capability.

While Musk's company is known for its sleek, battery-powered electric vehicles, it has always been more than just a car company. Its official mission is to accelerate the transition of the world into sustainable energy.

In storing the electricity produced by solar and wind, utility-scale batteries are needed. They can also become lucrative opportunities as battery owners can sell it back to the grid when the electricity prices are high, Interesting Engineering reported.

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