Sizing Your System
Selecting the appropriate solar energy system depends on factors such as the site, design, and heating needs of your house. The local climate, the type and efficiency of the collector(s), and the collector area determine how much heat a solar heating system can provide. It is usually most economical to design an active system to provide 40%–80% of the home’s heating needs. A small system providing as little as 30% of your hot water can be very efficient and cost effective! If the budget is tight, consider getting a smaller system. More panels can be added later. The important thing is to take that important first step to go solar!
General Sizing Guidelines
Skyline1, 2 and 3 Systems for 75 to 90% coverage in warmer, sunny areas, use two 10-01 collectors or one 20-01 collector (20 square feet) for each two to three people in the household. For example, a family of 4 should have four 10-01 collectors or two 20-01 collectors (40 square feet).
Skyline4 and 5 for 60 to 70% coverage in areas subject to hard freeze and a lot of clouds, start with four 10-01 or two 20-01 collectors for the first two people and then two 10-01 collectors or one 20-01 collector for every additional two people. For example, a family of 4 should have six 10-01 collectors or three 20-01 collectors (60 square feet).
TROPICAL and TEMPERATE SYSTEMS may allow you to use your existing electric water heater for open-loop systems 1, 2 and 3, or you can add a low-cost water heater for solar storage to your existing water heater. You need at least 1 gallon of storage for each square foot of collector area. It is desirable that your storage tank be at least 50 gallons of storage for up to 40 square feet of collector area, although a 40-gallon water heater can work well with up to 30 square feet of collector area. Generally, the larger the water heater the better, up to 2.5 gallons per square foot of collector area in sunny areas.
FREEZE PROTECTED SYSTEMS 4 and 5 use an excellent Rheem / Rudd or Richmond (all the same manufacturer) 80 Gallon Storage tank with a very efficient 120 foot “wrap around” heat exchanger. For a closed-loop system using an existing tank or added standard tank, an optional system 4 “POWER ROD” or”DRAIN BACK” external heat exchanger is available. They use a second pump for the domestic water loop and a tank top “Quick Connect,” to the storage tank.