Renewable energy opportunities have historically fallen as the "little brother" to mainstream energy sources such as coal and natural gas. Although some advancements have been made in the storage arena, the cost to supply the same power needs all-in just weren't comparable. However, Tucson Electric signed a deal this past week to supply solar and storage at 4.5 cents per kilowatt-hour over the next 20 years. "That's less than half the price of retail electricity power and a price low enough to compete with natural gas, coal, and nuclear power head to head in wholesale markets for what some might call 'baseload' power." The economics of this deal have the potential of exponential growth for solar energy around the world so long as the cost to produce & store it stays below other energy sources.