How would you like to take some lawn waste, use it to heat your hot tub for 18 monthsandbe left with a huge pile of rich compost at the end of the project?
It sounds like the last scene from Back to the Future, right?
Well, Tom Bartels of Durango, CO is a very inventive gardener and has figured this out. The best part is that its a project that anyone can do with enough space and time to assemble it. The materials are all readily available, no flux capacitor necessary.
How It Works
You know how compost gets hot as it decomposes? Most gardeners would be familiar with that effect but few have ever considered harnessing that heat for any real purpose. But it can be done.
Tom uses a large quantity of wood chips (and a few other minor ingredients) to power his off-the-grid hot tub. It ends up being a 6 foot tall compost pile that he insulates with leaves. The hot tub itself is insulated only with straw bales and a foam topper.
He uses an electric pump to circulate the closed-loop system, which costs him a whopping $3.27 per month in electricity. Hook it up to a solar panel and it would be totally off the grid!
Consistently Hot Water in Freezing Weather
The water temperature in the hot tub stays between 104 to 110 degrees Fahrenheit all day, every day. Any time he wants to take a dip, the water is piping hot, without fossil fuels used to heat the 250 gallons of water.
All his data collection for the project was done over 2 months from mid-December to mid-February in Colorado with nighttime temperatures in thesingle digits.
Tom estimates that this heat production will continue for 18 months (!) after which the temperature will decline due to the compost maturing.
Pays for Itself in Year One
The cost to set all this up was about $700, mostly for the pump and pipes. But get thisthe market value of the organic compost is $700-$1,200!
So it pays for itself (or more) in the first year; every year thereafter is effectively free because the pump and piping are reusable and the wood chips that provide the fuel are waste material that landscaping companies are happy to get rid of.
Use It for Anything
Tom made a hot tub but what he created is just a system that produces heat from yard waste. You could use that heat for any purpose including:
Heating a house using a radiant floor
Heating a green house
Heating aquaponic fish tanks
And more; its limited only by your imagination…
Want More Info?
You can get complete details on how to create this system for free, fromToms website. He teaches this method in one of hisfree webinars.
Sabrina Wilson is a natural health enthusiast and a staff writer for the Organic Daily Post. Originally from Boston, MA, she is a recovering Lyme disease sufferer who attributes her recovery to naturopathic remedies and an obsessively clean diet. Find similar posts on Twitter @organicdailypst
Disclaimer: The views expressed above are solely those of the author and may not reflect those of Care2, Inc., its employees or advertisers.
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