180 Evacuated Tubes heat a 900 gallon heat storage tank with circulating Glycol. The 900 gallon tank heats domestic hot water and FHW heating. Generally, the backup wood/oil furnace only comes on intermittently from November-February. We have infinite storage of electricity thru PSNH for $12 a month but a only few days of heat storage in the heat storage tank thru winter. We put an 12KW electric "on demand" water heater on the output of the heat storage tank to keep the domestic hot water temp at 130 degrees. Works GREAT. You always know what your shower temp will be, no matter what the weather has been.

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Quick Facts
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Energy Needs Met


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Energy Needs Met


or more of space heating

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What You Need to Know


180 Apricus Evacuated Tubes on the South gable end of the house, mounted vertically. By mounting them vertically, you avoid drastic overheating problems in the summer, but keep high efficiency in the winter. Also, snow won't cover up the tubes if vertical.

Other Benefits:

With wood, then oil as a backup, there is never a worry about fuel oil cost od availability.

Maintenance Requirements:

none so far.

Efficiency or Sustainability Improvements:

Added a 12KW whole house hot water heater to the output of the heat storage tank. No matter how many overcast days or what the heating load is, domestic hot water comes in at 130 degrees. We have a massive electric storage at PSNH, but limited heat storage in the tank; so this works great!

My Motivation:

Wanted to be able to provide heat and hot water no matter what.

Experience with Installer:

Revision brought their Solar Army in for a week and did all the NH rebate paperwork perfectly.

Open House Info:

OCTOBER 5TH, 2013 from 8AM to 4PM Solar PV, Thermal and EV OPEN HOUSE 100% whole House solar electric, charging 4 electric cars, heating 4 garage spaces, heating a chicken coop, heating a cellar. PSNH pays us…with over 6 Megawatts “in the bank” Possible !00% thermal with wood backup. See “stick on” PV, Tracker PV, Rack PV, Xantrex XW system, Battery system and a microinverter system AC Coupled to the Battery system. See a Tarm 2200 Wood/Oil FHW boiler, a 900 gallon heat storage tank and 180 evacuated tube Thermal solar system. See a 2011 Tesla Roadster 2.5, a 2012 Tesla S Signature Performance and a Chevy Volt.

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