Guardian: The global deployment of renewable energy from wind, solar and biofuels grew in 2012 but the income from the sector remained flat due to the plummeting costs for solar photovoltaic panels. The revenue for the three technologies increased by 1% globally to $249bn in 2012, according to the Clean Energy Trends 2013 report released on Tuesday by renewable energy research firm Clean Edge. "We always knew each doubling of [solar PV] installation would reduce prices about 18%," the Clean Edge founder,...