Size matters in solar physics. Scientists in Germany may have just unlocked the next generation of clean energy by generating record-breaking power on a piece of material larger than a postage stamp.

FIVE AT FIVE. ALL RIGHT. A LOT OF PEOPLE IN MASSACHUSETTS LEASE THE SOLAR PANELS ON THEIR ROOFS. IT’S A GREAT WAY TO AVOID THE BIG UPFRONT COSTS OF GOING GREEN. BUT WHAT HAPPENS WHEN YOUR SOLAR ...