Private equity group Terra Firma just spent big money on solar power generation, acquiring Italy's largest solar power company for 670 million euros ($1.05 billion U.S.), according to the Financial Times.

It's the third big renewable energy deal for the U.K. investment firm, which specializes in buyouts of large businesses that are in need of a new direction.

The takeover of the Rete Rinnovabile from Terna, Italy's national grid operator, will give Terra Firma control of an estimated 10 percent of Italy's solar power market, which has been on the rise despite a general global slowdown in renewable energy spending due to the economy.

The Italian government recently set long-term tariffs for solar power providers that make the technology appealing to investors.

Terra Firma previously bought out Everpower, a U.S. wind farm developer, for $350 million in December 2009. The firm also owns Infinis, a business that generates power from landfill gas. Infinis is now the U.K.'s biggest producer of renewable energy and is exploring other clean energy sources such as wind.

The deal to buy Rete Rinnovabile is expected to be completed by March 2011. Reuters reports that Terna will reinvest the proceeds of the sale in future energy projects, including solar power.