patent pending retrofit system for replacing almost all of the owners' fossil fuel use, at a reasonable price.

EnergySage Customer
Quick Facts
Energy Needs Met

75% to 99%

of hot water


What You Need to Know


Retrofit, air to rock capture, extremely slow air to hot water transfer, roughly two days of heat storage capacity.

Other Benefits:

A larger version of this system provides both building heat on demand (at 6:00 a.m. before sunrise for example) and hot water on demand. A normal-sized retrofit system might displace 80% of total fossil fuel use. Most solar system retrofits go to 50% of hot water only. If the true environmental cost of petroleum is $12 or $15 per gallon, 80% or better solar displacement is the best way to go. Air and rocks are a maintenance-free medium except for mold. So, we eliminate the mold issue by never turning off the heat, never blowing moisture into the rock bed and never blowing air from the rock bed into the building. Problem solved! Air ducts are less efficient than water pipes, but it turns out that they're quite effective and solve a number of maintenance issues. Our patent-pending rock bed design takes 12 hours to warm a day's hot water in a tank, but it gets the job done. Our collector awning is hurricane-resistant because it spills wind gusts.

Maintenance Requirements:

In 40 years the fan might need replacement. Otherwise, absolute zero. That's a unique benefit that fossil fuels can never match.

My Motivation:

The market is wide open for a competitive solar retrofit that displaces 80% of fuel use. Nobody does this yet. A revolutionary solar system changes the world, while a million "me too" systems don't do that much. Which side of history will you have wanted to be on, in retrospect? If your only climate change goal is to make money, then your rule is, "the second mouse gets the cheese", but I'm no mouse.


If your deepest goal is to become a minor fashion statement, try the stuff off the rack at the store. If your deepest goal is to change the world, eventually you'll become the ultimate fashion statement and you'll put up with the fuss.

Open House Info:

We'll probably limit our hours between 1:00 and 4:00. We're not finished installing.

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