The company that drew attention after sending huge electricity bills to customers after last month's blackout-causing winter storm in Texas has filed for bankruptcy protection.

Griddy Energy sold power to consumers at wholesale prices plus a $9.99 monthly fee. Its rates skyrocketed during the February deep freeze, when state grid operators raised wholesale prices.

The company blamed its situation on the Electric Reliability Council of Texas, which operates the power grid in most of the state. Griddy said ERCOT kept wholesale prices at the state's legal cap — $9,000 per megawatt hour — for too long.

"The actions of ERCOT destroyed our business and caused financial harm to our customers," Griddy CEO Michael Fallquist said in a statement.

Griddy said in a filing Monday in the southern district of Texas bankruptcy court that it has assets worth up to $10 million and liabilities of up to $50 million.

Prices began to spike as last month's Arctic storm approached Texas and many power generators shut down for various reasons — wind turbines froze, and frozen natural gas wellheads prevented some gas-fired power plants from receiving fuel.

Griddy warned customers that they would face price increases and told them to attempt to switch to another provider, but some who didn't were hit with bills in the thousands of dollars.

The Texas attorney general is suing the company, which is headquartered in Playa Vista, California.