L-M Residence: Solar Hot Water, PV, and Pool Heating
The Highlands, Shoreline, WA

The L-M family wanted to reduce their energy footprint and reduce usage of fossil fuels in their home in The Highlands. Being a wooded area, a careful site evaluation was conducted to determine expected outcomes and best locations for specific solar technologies. A 3-part solution was developed: Solar Domestic Hot Water (DHW), Solar Electric power, and Solar pool heating system. A professional roofing company was brought in to work with Northwest Mechanical on the shake roof installation. A 60-tube Apricus solar domestic hot water system ties into a 119 gallon stainless steel heat exchanger tank and a 119 gallon indirect fired hot water heater and Buderus high-efficiency boiler system. The solar differential controller activates the closed solar loop only when sufficient solar energy is available to heat the water in the solar tank. An existing chimney was used for both the boiler's new vent liner and the solar supply and return lines. This system was the first solar project allowed in The Highlands. The second phase of the project was the installation a 3.6 kilowatt solar electric system on another portion of the roof interconnected with the home and the grid using a Xantrex 3.3 inverter. 18 Sanyo 200 Watt modules were mounted on a Uni-Rac aluminum mounting system. Roof jacks and standoffs are uses on shake roofs to insure maximum water protection to the roof. The array was set up in multiple strings so that early morning shading issues would still allow the rest of the system to function well. Phase 3 was the installation of five unglazed Fafco 4'x12' SunSaver pool collectors to heat the backyard lap pool. Sensors for pool and rooftop temperatures are used to insure pool water is only sent to be heated in the collectors when the sun is shining and not at nighttime. Existing landscaping and sidewalks meant that the supply and return lines had to be underground, and the routing to the rooftop was put in an inconspicuous location. Northwest Mechanical also installed the high-efficiency boilers and indirect fired main hot water heater at this residence, providing an entire package of energy efficient and solar solutions.