For some years already, Nevada's political leaders have talked about making the state a Mecca for solar energy. It would diversify the economy with a high-tech industry and it would take advantage of our unending sunshine. The County Commission recently gave the green light to a new solar project near Laughlin. Critics decry the waste of government resources for a new and unproven industry. A new report from the Brookings Institution promises to give an accurate count on green energy. So what is the future of the green economy in Southern Nevada and elsewhere in the nation? Is the glass half full or half empty?