Agence France-Presse: President Barack Obama Tuesday announced the largest modernization of the US electricity grid in history, in a 3.4-billion-dollar bid to launch a new era of renewable energy consumption. The president toured the largest solar energy plant in the United States to unveil the program, under which 100 firms, manufacturers, utilities and cities were awarded grants worth from 400,000 to 200 million dollars. The new plan will help build a nationwide “smart energy grid” to cut costs …