Bloomberg recently reported that six out of the 10 largest homebuilders are incorporating solar panels in new construction. It's cheaper to do it as the home is being built, and homebuyers can roll the cost into their new mortgages. Should investors care? In this video, Fool.com contributor Aimee Duffy explains what investors need to know about the partnership between homebuilders and solar manufacturers, and how this story indicates important change in other sectors as well.