At the end of June 2007 we installed a solar hot water system from Butler Sun Solutions . It is a closed loop antifreeze system that heats water in our existing propane hot water heater using a Solar Wand heat exchanger. We have four Fireball 2001 collectors from ACR Solar International for a total of about 40 square feet of collector area. On the left side of the collectors is a small 21 W Uni-Solar photovoltaic module that powers the Ivan Labs EL-SID pump, which moves the antifreeze fluid through the collector loop.
The system was largely installed by Lucas Christy of Solar Gain Services
of Center Colorado (719-588-3044) with help from Frank. Luke did a
very professional job, as can be seen in the following pictures:
Collector front view
Collector side view
Collector back view
Top of tank components
The hot water tank has since been insulated with an R11 fiberglass blanket
and some Thermax rigid insulation.
We are monitoring the performance of our Butler solar hot water system by measuring temperatures of the top of the hot water tank and of the collector return loop (before it enters the Solar Wand). The temperature probe on the top of the tank is on the outside of the inner tank under some insulation, but it presumably is still cooler than the actual water temperature. The temperatures are measured every five minutes (along with the solar basement temperatures). The solar hot water temperatures for the past three days may be viewed on this graph . From the nightly tank cooling rates we determined that the Newton's Law of Cooling time constant is more than four days. The additional tank insulation is important for keeping the water hot through cloudy days.
The hot water tank temperatures are summarized with this daily average graph:
Click on the graph for a larger version.
