He asks the royal leather worker to cover his kingdom in leather, so wherever he walks, he will never stub his toes.
The leather worker pauses and then suggests to the king that if he covered his feet in leather he could walk wherever he chose, anywhere in the world.
This is the story about the first pair of shoes.
It's emblematic of the way many people look at renewable energy. Right now we are trying to cover the world with solar panels or wind turbines.
But what if we decided to look at the world as its own solar panel?
I'm talking about geothermal power and the good news is we already have the technology to tap into it.
So how big is U.S. geothermal power?...
MIT estimates that just 2% of the heat below the United States at depths of 3-10 kilometers would be enough to supply 2,500 times the nation's current energy needs.
The compelling part about geothermal energy is that it isn't as cost-intensive as solar or wind. It's also far more reliable - available 24 hours a day, 7 days a week at consistent, predictable levels.
That means more geothermal energy can be uploaded to the grid far more efficiently and on a larger scale than either solar or wind.
This technology is also proven and is already in commercial and industrial use west of the Mississippi and for residential applications around the globe.
And now, there are two factors that have the potential to put this clean energy resource on a level far beyond its previously limited scope.
Geothermal Power for Your HomeThere are two types of geothermal that work off the same underlying principle.
Residential geothermal - the kind you would run a house on, uses the "earth-as-solar panel" concept.
In this case, geothermal heat pumps take advantage of the solar energy stored just below the surface of the ground.
If you're a solar power fan, then consider this a passive solar unit because the earth is a highly efficient photovoltaic panel: 40% - 60% of the Sun's energy is directly absorbed into the ground.
In cold months the pump pulls the heat from the earth and heats your house. Residual heat is used to heat your water.
Conversely, in the summer months the heat is pulled from the house and pumped into the earth loop where it dissipates into the earth and the cool solution in the pipes acts as a refrigerant.
This video from GeoSystems does a good job of giving you an overview of the process.
Believe it or not, with geothermal energy, you can cut your heating and cooling bills by 70% and have virtually free hot water whether you live in southern Florida or northern Minnesota.
In fact, its potential for residential use is so strong both the Department of Energy and the Environmental Protection Agency have dubbed individual geothermal as "the heating system of the 21st Century."