This is Planet Money from NPR.

This is so cute.

This is like a Hobbit House, Jillian.

This is really cute.

This grass all over the house.

This Hobbit House is perched on a hill in a tiny town in Northern Bavaria, Germany.

Picture like a, I don't know, like a little fairy tale log cabin.

Yeah, there are these flower boxes on every window.

It's literally built into the side of a hill. The roof is like covered in grass.

It's so good to meet you.

Guten Tag.

Guten Tag.

Will you come in?

Yes.

In this little Hobbit House, a regular sized man named Hans Josef Fell revolutionized the way the world gets its energy.

Hans Josef gives us a tour of his home, which is the most eco-friendly place I've ever seen.

He walks us over to the indoor greenhouse covered in plants with its own well.

This is a water from rain.

He takes us outside to a homemade pond where, apparently, Hans Josef swims every day.

Even in wintertime swimming, it protects you from diseases.

But the reason we are here is because of what's on top of the house.

Hans Josef walks us into the backyard so we can see onto his roof.

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