Over the past decade, the cost of a solar electric system (solar PV) has dropped significantly. With the advent Made-in-WA solar components as a result of a higher cost-recovery Production Incentive rate paid to WA property-owners who install grid-tied solar, and the numbers of homes with new solar systems in our state has skyrocketed.
You too can get clean renewable solar electricity to meet a portion of your annual energy needs.
How Much Electricity Do You Use?
When determining what solar PV can do for you, the first question is how much electricity do you need? That is, how many kilowatt hours per year of electricity do you currently use? If your home is all-electric, then in may not be possible or cost-effective to offset 100% of your electric bill, but if you heat your home with gas or another fuel, then you have much lower need for electricity. Before you call a solar installer for a bid, gather up your electric bills and figure out your usage. Then the solar system can be tailored to both your site and your usage.
Evaluating Your Home for Solar
Sunlight is the fuel for all solar technologies, and the term solar resource refers to identifying how much of it is available in a given collector area. Three significant factors affect the power output that you can expect from a roof or ground mount solar installation: direction the roof is facing, shading, and roof pitch.
- Direction: South-facing is ideal. Southeast and southwest facing roofs will still receive a lot sun. East and west facing will receive less, but may still receive enough sun. Roofs that face north facing will not receive enough of solar resource to make sense.
- Shading: Solar panels should have direct access to the sun, with little to no shading, for 6 hours of direct sun year-round. Common things that may reduce sunlight are shade from buildings, trees, hills or roof features like large chimneys.
- Pitch: The ideal roof is between 20 and 35 degrees, though steeper and flatter roofs may still work.
- Sufficient space is also a factor. When designing solar for a particular roof, the panels must be arranged not to cover up vents, skylights, chimneys, etc. Often the limiting factor on system size is the available roof space.
- You can learn a lot about your site’s possible power output from the PV Watts website where you put in your address then draw a solar system on your roof and see what is possible.
For an accurate cost estimate of solar for your home, a solar installer should visit your home to measure solar exposure and roof space, evaluate your electric breaker panel, evaluate your site, make a plan for panel locations, wire runs, inverters, production meter, and any other components. They will discuss with you any site specific concerns or factors that affect cost.
- The solar installer will design options for you taking into consideration things like fire code requirements for distance from the peak of the roof.
- After the site assessment, the solar installer should provide a proposal with system options, estimated power output for each option, diagram or text explaining the rooftop plan, prices and terms of the contract.
- The solar proposal should estimate for you the annual and long term savings on your electrical bill, as well as payments to you from incentive programs and tax benefits so you can see the long term benefits, the upfront costs, and payback time period (return on investment) The following incentives apply if the home owner qualifies:
- 30% federal income tax credit.
- State of Washington Production Incentive – paid at a per KWH rate for the solar electricity your system produces before any gets used. Annual maximum of $5000. Program ends 6-30-2020.
- Net Metering – electric bill savings.
- System size <10 KW is sales tax exempt.
- Additional incentives that your utility may offer.
If your residence is governed by a Homeowners Associations (HOA's), visit this page of resources about Solar & HOA's.
Learn more about the Solar Incentives for Washington homeowners.
Price & Financing Your Purchase & Installation
Residential size solar systems (under 10 KW) are currently state sales tax exempt. System prices range from around $15,000 to $45,000 depending on system size, specific components, complexity of installation and other factors. So, it is about the same as buying a new car.
These financial institutions, based in Washington, specialize in solar-specific loans for home-owners:
Another option is to utilize a Home Equity Line of Credit on your existing home loan.
The Clean Energy States Alliance in partnership with the federal Office of Energy Efficiency & Renewable Energy published a free guide to help homeowners navigate the complex landscape of residential solar PV system financing. Download the complete Homeowners Guide to Solar Financing (PDF).
Hiring a Contractor
Do your homework. Call more than one installer and get several bids before choosing a company to install solar on your property. Review our list of Consumer Questions!
- Once you and your chosen installer agree on the system details, either you or your installer must apply for the necessary building permits per city ordinance, utility interconnection, and incentive paperwork for annual incentive checks. Your installer will create a line diagram which is part of the application.
- Once your utility approves your interconnection, an installation typically lasts one to three days for residential rooftop; longer for ground mount.
- On the last day of installation, Washington Labor & Industries (L&I) conducts an electrical inspection.
- Within five to thirty days, your utility will install a new production and net meter and then your solar system begins producing power.
- You probably want to add your solar system to your home-owners insurance policy.
- Use your paid invoice to document your purchase to get your federal tax credit.
- Apply annually to receive your annual cost-recovery Production Incentive payment by check.
- Check the system at least monthly to make sure it is working.
- Clean the solar panels at least annually or more often if you notice dust and pollen accumulating. Follow manufacture’s guidelines.
International Fire Code dictates how much of the roof can be covered with solar panels and how close the panels can go to the ridgeline. Click for more information.