Removing my old solar augmented heating system

In 2001 my ex-wife and I purchased this property in rural Maine that included an open two-story barn that I converted into a heated and insulated workshop. Moving from California to Maine I was well aware I would need a heating system, but wanted to keep the carbon footprint as low as practical. With that in mind I super insulated the building with a combination of spray in foam and fiberglass resulting in R30 walls and R40 roof insulation.

Original solar collectors in 2003

I then designed a hydronic heating system that included in-floor heating and radiators upstairs.  The heat source came from a Bosch Aquastar propane heater and 4 large 4 x 8' solar water collectors. I was not particularly impressed with the contribution from the solar collectors and my propane bills were relatively substantial over the years. So a few years later I installed a wood stove as a backup heating system which worked out really well. I now use it whenever the temperatures outside drop below 20°F.  I now purchase about one cord of fire wood per year and augment that with wood that I harvest from my own property and other places.

new solar electric panels installed bottom right

In November 2021 I self installed a MrCool heat pump system designed to heat the entire building using only electricity which is mostly renewable thanks to my substantial solar array and renewably sourced utility electric supply. I then removed the solar collectors and replaced them with six solar panels, you can see a video about this process here.  As part of the removal process, I had a great deal of left over copper pipe that I was able to sell to a recycling company for over $130.  I also sold the four large solar collectors to someone who could make good use of them.

I kept the interior plumbing and heating system thinking that I could use it as a backup.  But in the last few years I have not used it so I decided to decommission it.  The large insulated tank seen in the picture is an 80 gallon water heater used as the solar thermal heat storage tank.  And of course there is a great deal of copper plumbing parts, pressure tank, and the propane boiler.

I took everything apart very carefully so that the copper could be recycled and other parts could be reused.  I literally saved every nut bolt and screw along with wire nuts and every other small component and put them back into my storage system.

 

There is a local guy who recycles metal as his side hustle, so he came by with his large trailer and hauled off all the parts that could be recycled.  I'm sure he made some good money on all that.

Here is a view of my utility room all cleaned out.  I'm now waiting for the propane utility company to disconnect the line so I can remove the boiler.  I'm hoping to find a buyer for this well used, and well loved Bosch Aquastar unit that is still working great.  The interesting feature about it is that it does not require any electricity to operate so it's optimal for off grid situations.

 

Here are before and after views of the manifold and PEX plumbing that feeds into the floor.  I left the PEX in place just in case a future owner chooses to install a radiant heating system in the floor.  Here is how I installed the PEX.

As someone who is committed to living sustainably, I am invoking the 4 R's - Reduce, recycle, reuse, repair.  So in addition to scrapping out the metal I also donated some of the useful plumbing parts to the Habitat for Humanity Re-store near me so that someone else can use them.  And I'm also selling some of the more valuable parts such as the pumps on eBay as they are in good usable condition.  All in all, very little went into the trash. 

It was sad to say goodbye to all of this equipment because it took me many, many weeks to design and install back in 2001.  Back then, heat pump systems were not common and very expensive.  What has happened over the intervening years is that solar power system installers are also now installing mini-split heat pump systems because it is a natural pairing.  Heat pumps are very efficient and have the benefit of both heating and cooling.  

While heat pumps are relatively expensive, and installation costs can range from $5000-$10,000, I installed my own heat pump system in the workshop at a cost of less than $2000 and another larger system in my home for less than $2800.