If you’re building a new home or refinancing, the economics are very attractive. Including the price of a solar water heater in a new 30-year mortgage usually amounts to between $13 and $20 per month.
The federal income tax deduction for mortgage interest attributable to the solar system reduces that by about $3–$5 per month. So if your fuel savings are more than $15 per month, the solar investment is profitable immediately. On a monthly basis, you’re saving more than you’re paying!
To get the full benefits of a solar heater you must have an area for the solar collectors that is large enough and has the proper exposure to the sun. A flat roof is ideal because the collectors can usually be oriented to face the sun directly very easily. If you install the collectors on a pitched roof, the ideal direction the roof should face is south.
The collector area required will depend on the daily amount of hot water use, the type of collectors used, the orientation of the collectors and your geographic location. If you consider a standard “package”, you should be sure it is sized appropriately for your specific installation.
Installation Conditions For A Solar Water Heater
If you choose a “Passive” solar water heater, the storage tank(s) will be on the roof. In this event, simple structural bracing may be required. Active solar systems do not normally require structural calculations or roof bracing, because the weight of the collectors is well within normal roof load limits.
An “Active” solar water heater uses a small pump for solar collector circulation, and does not require a tank on the roof. A “Passive” solar heater depends on thermosyphon action, so does not use a pump, but tanks(s) must be on the roof.
Operation & Maintenance
Your solar water heater should be supplied with operation and maintenance instructions. You will find that there is little, if anything, for you to do once the installer has started your system and checked its operation for the first time. Properly designed solar water heaters are completely automatic and are left in operation year-round. Active systems have a small electronic control with one or more indicator lights to let you know if there is a malfunction. Be sure the instructions specify how your system is protected from freezing! Freeze damage is possible anywhere in California.
Shopping For A Solar Heating System? ~ Know exactly what you are getting and for what price, and make sure you are dealing with a licensed solar energy contractor.
1. Get specific details on how collectors will be attached to the roof, are they structurally attached through into rafters, and are they elevated to allow for proper drainage, to prevent roof rot and debris buildup.
2. Get a dimensioned scaled sketch or drawing showing the number and location of collectors and schematic diagrams showing plumbing and control arrangements.
3. Get specification sheets and warranties on collectors and control. The manufacturers warrant these items.
4. Get a copy of the certified solar test ratings for the collectors, or a written statement listing the certification.
5. Make sure the control has an Underwriters Lab (UL) label. This can be confirmed by the manufacturer’s specification sheet or literature.
6. Make sure the work contract specifies the manufacturer, model, and size of the solar panels and the exact model number of the control.
7. Make sure the collectors have current approval of the city or county, if required, or IAPMO approval otherwise.
8. Specify a date when the installation is to be completed.
9. Specify who is responsible for clean-up after installation.
10. Specify exactly what is to be done before progress payments are made, and when final payment is to be made.
11. Specify that the installer will demonstrate how the system is operated and will provide written operating instructions.