NEW YORK (TheStreet) -- Warren Buffett stole headlines this week with the announcement that MidAmerican Energy Holdings, a Berkshire Hathaway (BRK.A) branch, was venturing heavily into the solar energy sector.Fans of the billionaire investor may be tempted to follow his company's lead and load up on alternative energy at this time. However, taking into consideration the current market environment, this is one Buffett-play I urge conservative investors to monitor from the sidelines. As of Thursday, the financial terms of Berkshire's latest deal have remained undisclosed. However, many have placed a $2 billion valuation on the southern California-based Topaz Solar Farm. Reportedly, upon its completion, the project will be one of the largest photovoltaic power plants in the world.