Wind, solar and hydroelectric energy are not new, but these renewable sources only account for a small portion of the energy market. One reason is that storing all that power can be pretty difficult and expensive. But that could be changing.

Recently, a renewable energy company bought the rights to develop the largest solar farm in Texas. Now a massive energy storage project is underway in west Texas, aiming to pull off what Tesla founder Elon Musk managed to do in Australia last year – building a battery-powered system that can store large amounts of energy.

Rye Druzin, a business reporter for the San Antonio Express-News says that Musk’s battery in Australia is the size of a football field. Druzin thinks the battery in Texas will be a bit smaller. But it can “power a couple thousand homes for about four hours,” he says.

Druzin says that energy producers are concerned about the cost-effectiveness of using batteries.

“People are concerned about whether a $500 million investment on a battery would actually be able to pay itself off,” he says.

To test the batteries, Druzin says energy producers are investing in smaller versions of these batteries. This allows them to assess whether the batteries will work well before making larger investments.

“It’s a small amount but it’s one of those small steps toward what the future may look like,” Druzin says.

Written by Manu Schneider.