NEW YORK (TheStreet) -- Shares of SunEdison , a U.S. solar panel maker and power plant developer, are up 2.23% to $22.90 in pre-market trading today after the company bought Solar Grid Storage LLC for an undisclosed sum to combine battery technology with its projects that generate renewable energy, Bloomberg reports. Solar Grid has four projects in operation and is developing at least three more this year, Solar Grid Storage CEO Tom Leyden told Bloomberg.