Michigan-based Great Lakes Electric has a solar hot water product with evacuated tubes that allows for creative building-integrated solar hot water. By releasing the restriction of roof mounting, as with typical solar hot water products, GLE’s unit allows for more innovative placement and ends the worries of roof penetrations and units looking like large black rooftop tarps.
These evacuated tubes are made of two concentric tubes, the center filled with water in the collector pipe and a second to form the vacuum. The vacuum gap between the collector pipe and exterior allows for a reduction in heat loss over flat pane collectors.
Evacuated tubes generally outperform traditional solar hot water designs in cloudy or cold conditions while flat pane systems typically have the efficiency edge in direct sunlight conditions. (Similar to the comparison between the thin film amorphous silicon (peel and stick) solar vs traditional PV panels).
When designing the system it should be placed in a location with East – West exposure to allow for full day solar collection. With larger diameter evacuated tubes compared to most other evacuated tube manufacturers, the system requires less installation area by allowing it to mount vertically.
GLE’s introductory unit retails for $2,500 and produces approximately 56,600 BTUs per day. With four different standard sizes GLE can select the proper unit for your hot water load. The system is recommended for any hot water need, such as pool heating, domestic water heating and radiant floor heating.
Photo Credits: GLE Solar.