State regulators have re-issued approval for a controversial solar power plant in the Southern California desert after its opponents claimed it had no business being licensed in the first place, Reuters reports.

Permission to construct the $2 billion Calico plant was reinstated by the California Energy Commission to Tessera Solar after the commission pulled back permission last month. The California Unions for Reliable Energy opposes the plant because it believes the environmental impact will be damaging.

Reinstating approval permits Tessera Solar to begin construction and the company hopes to do so by the end of the year in order to capitalize on incentives including coverage of 30 percent of the cost via a federal cash grant project.

Opponents also have 30 days to file challenges to the project's approval. The Sierra Club and Californians for Reliable Energy told commissioners they are considering a legal challenge based on defense of desert tortoises and additional wildlife.

Calico is projected to have 26,540 solar dishes called Suncatchers. Each Suncatcher is 40 feet high and 38 feet wide.