It's crazy. It'll never work. They cost too much. They'll crack. They're too delicate. You'll slide off them. Oil companies will never let it happen.

Scott Brusaw, an electrical engineer from Idaho, has heard it all before. Over the past eight years, skeptics (like this one) have been telling him his concept for solar roadways — replacing America's roads with solar panels, creating a power grid where pavement used to be — won't work. But Brusaw suddenly has a reason why it will — actually, 2.2 million of them.

Solar Roadways' crowdfunding campaign, which closed on Monday, raised $2.2 million — more than double what Brusaw was seeking — in just two months. The campaign, the most popular in Indiegogo's history, attracted more than 48,000 backers from all 50 states and 165 countries.

"It's been humbling," Brusaw, 56, told Yahoo News. "Really, really humbling."

The success can be attributed, in part, to a cheeky seven-minute video ("Solar FREAKIN' Roadways!") that has been viewed more than 16 million times on YouTube.