In Texas, an expanded renewable energy mandate finally got overwhelming approval by the state senate by a 24-7 majority.

Using the same Renewable Portfolio Standard that has made the state a national leader in wind power, the bill – SB541 – now offers an incentive to the solar power industry to expand under Texas’ wide skies and ever-present sunlight.

According to Sen. Kirk Watson (D-Austin) the bill – SB541 – encourages the development of solar energy plants, and builds on SB545, passed in April, which created a statewide rebate program for solar rooftop installations. Thus, SB541 represents the commercial level of solar capacity that will meet a mandate of 1,500 megawatts of renewable energy by 2020.

Together, the bills give Texas an around-the-clock baseload of renewable energy composed of solar energy during daylight, biomass and geothermal to take up the slack during cloudy days, and wind power, which generally maximizes capacity at night.

To facilitate grid connectivity, commercial-scale solar projects can be located beneath wind turbines, since Texas has already committed to a $5- billion transmission upgrade to serve proposed wind installations.

Texas is already home to two large solar manufacturing firms: Austin-based Applied Materials, the world’s largest maker of peripheral equipment for photovoltaic (PV) installations; and Brownwood-based Barr Fabrications, which made the steel supports for Nevada Solar One, the nation’s largest solar thermal power plant at 134 million kilowatt hours per year, or enough to power more than 15,000 households. Nevada Solar One officially went online May 13.

Approval of SB541 was triggered, according to some experts, by a report by Texas Public Utility Commission concluding that a failure to move away from fossil-fuel generation could cost the state’s ratepayers as much as $10 billion a year, or $27 a month, in carbon emission’s penalties, whether via the Waxman-Markey cap-and-trade provision or actual taxes.