To get a handle on whether solar is right for your house, consider your roof, your energy use, and your estimated cost and payback period.
1. Is your site suitable for solar?
The orientation of your roof and shading by nearby trees will determine how much solar energy you can potentially generate. Additionally, the condition (age) of your roof depends on whether PV panels are a good investment before you replace your roof. Google’s Project Sunroof is a simple, fast way to get started. Enter your address and you’re on your way.
2. How much energy do you use and need?
Identify how much energy you’re currently using and how that might change in the future to determine the size of your system. A home energy assessment (see “Learn about your house”) can help you flesh this out.
- To determine current electricity use, look at your electricity bills for the past 12 months;
- Consider plans that will increase future electricity use (e.g., an addition, an electric car, a heat pump);
- Consider energy efficiency upgrades to reduce the size of system you need.
3. How many solar panels do you need and what will it cost you?
To estimate solar potential on your roof and the costs, savings, and payback period of a photovoltaic system, the Department of Energy recommends two websites listed below.
- Energy Sage, for free estimates, financial analysis, and contact information for qualified installers in the area; and
- PVWatts, the National Renewable Energy Lab’s online tool for consumers to calculate energy production and costs.