Inside a sprawling single-story office building in Bedford, Massachusetts, in secret room known as the Growth Hall, the future of solar power is cooking at more than 2,500 °F. Behind closed doors and downturned blinds, custom-built ovens with ambitious names likeFearlessandIntrepidare helping to perfect a new technique of making silicon wafers, the workhorse of today’s solar panels.

If all goes well, the new method could cut the cost of solar power by more than 20% in the next few years.

This humble wafer will allow solar to be as cheap as coal and will drastically change the way we consume energy,” says Frank van Mierlo, CEO of 1366 Technologies, the company behind the new method of wafer fabrication.

In Jan. 2015, Saudi Arabian company ACWA Power surprised industry analysts when it won a bid to build a 200-megawatt solar power plant in Dubai that will be able to produce electricity for 6 cents per kilowatt-hour.

The price was less than the cost of electricity from natural gas or coal power plants, a first for a solar installation.

The recent record-setting low-cost bid for solar power in Dubai harnesses thin-film cadmium telluride solar modules made by US manufacturer First Solar.

While solar power is just starting to reach grid parity, wind energy is already there.