Workers Stephen Janota, left, and Matt Bart, install Solar Service Inc. photovoltaic (PV) solar electric panels on the roof of a home in Park Ridge, Illinois, U.S., on Tuesday, Sept. 10, 2013. Solar panels are the next granite countertops: an amenity for new homes thats becoming a standard option for buyers in U.S. markets. Photographer: Tim Boyle/Bloomberg via Getty Images