Before you begin your solar journey, consider how long you plan to stay in your current home. If you’re thinking of moving soon, be sure to check out Moving with Solar Panels FAQ for helpful tips. 

Understand your home’s energy use

• Review your electricity bills: Gather the last 12 months of electric bills and calculate your average daily usage in kilowatt-hours, kWh. The standard range for solar home systems is 5-10 kWh.
• Get a home energy audit: Request a professional energy audit from your utility, or conduct a DIY audit to identify opportunities to save energy before going solar. 

Reduce energy use and improve efficiency

• Efficiency first: Identify and complete any energy efficiency upgrades before installing solar. This could include insulation, sealing air leaks, or upgrading windows.
• Upgrade appliances: Replace outdated appliances with energy-efficient models. Look for the EnergySTAR label.
• Consider heat pumps: If your heating and cooling system is due for a replacement, energy-efficient heat pumps can significantly reduce electricity usage.

Check out energy efficiency tips for ideas on how to lower at-home energy consumption.

Energy Efficiency tips from Safe Electricity 

How to set up a home solar energy system

There are four steps to follow as part of setting up a solar energy system at home: 

1. Choose your type of solar energy system
2. Check your roof for solar readiness
3. Estimate the size of your solar energy system
4. Plan for how you’ll pay for your solar panels

1. Choose your type of solar energy system

Deciding early on if you want to integrate battery storage is important. Even if you don’t install it now, considerations need to be integrated early on to make it possible later. This can also help determine the size of the solar energy system. 

Check your roof for solar readiness

• Roof age: Solar panels last 15-20 years. If your roof will need replacing soon, consider upgrading it before installing solar to avoid extra costs later.
• Sun exposure: Ensure your roof receives enough sunlight year-round. South-facing roofs without significant shading are ideal. 

Solar energy system options

• Grid-connected: Solar panels are directly tied to the grid. During the day, solar energy is used first. If the panels produce more than is needed, the excess is sent back to the grid, often earning credits through a system called net metering.
  • Read more about net metering below.
  • During a power outage, this solar system automatically shuts down. This safety feature prevents electricity from flowing back into the grid, which could put utility workers at risk while they complete repairs.
  • For grid-connected systems, the solar panels do not need to generate 100% of your home’s energy usage. Making your generation goal between 50-75% of your annual electricity usage is a good place to start, since electricity usage varies by season and time of day.
• Grid-connected and battery storage: Solar panels are still connected to the grid, but the battery can store excess energy. If there’s a power outage, the system automatically disconnects from the grid and continues to operate independently. The battery provides backup power, and the solar panels can keep charging it throughout the day.
• Off-grid: Completely independent from the grid. It relies entirely on solar panels and batteries to supply electricity. This requires careful planning to ensure energy needs are met year-round. Unless you’re in a rural or remote area, this is uncommon. 

3. Estimate the size of your solar energy system

Use this formula to estimate the system size needed to meet your solar generation goal:

System Size (kW) × Peak Sun Hours/Day × 365 Days × Panel Efficiency (0.80) = Annual kWh Production

Example Inputs for Illinois:

• Peak Sun Hours: 4 to 4.5 hours/day
• Efficiency Factor: Use 0.80 to account for long-term panel degradation (20%), shading, snow, and hot weather
• Annual kWh Production: Multiply your average annual energy usage by your desired offset percentage (e.g., 0.75 for 75%)

To find system size (kW): Rearrange the formula

System Size (kW) = Annual kWh Production ÷ (Peak Sun Hours × 365 × 0.80)

4. Plan for how you’ll pay for the solar panels

• Buy outright: You own the system and get the full financial benefits.
• Lease: A third party owns the system, and you pay a fixed monthly amount for the system.
• Power Purchase Agreement: You pay for the electricity the system produces, not the system itself.

Regulatory processes

1. You’ll need to work with your utility and local government to make sure the system is interconnected to the grid, and that the right permits are secured. 

2. Submit an interconnection application to your utility company. The application includes the technical specifications of the solar system and compliance with net metering requirements.
3. Whether you live in town or a rural area, it is likely that permits will be needed prior to the installation of your solar array. Always check with your city or county offices to verify what permits are needed, as it varies by jurisdiction.
4. Necessary permits may vary depending on whether the array is a roof-mounted system or a ground-mounted system.
   1. Types of permits can include building permits and electrical permits. In rural areas, building permits are sometimes referred to as zoning permits to indicate that the permitted use is allowed in your property’s zoning district.
5. Generally, your solar contractor will acquire the necessary permits, but make sure to clarify this with them or ask that the responsible party for the permits be named in the contract.
   1. If the contractor states it is your responsibility to acquire the permits, you will need to get documentation from the contractor to submit with the permit application(s). Typical documentation includes:
      1. A one-line diagram of the electrical components
      2. Specifications for the solar panels that will be installed on your property
      3. A site plan showing the location of the array–this is typically needed even if the array will be roof-mounted.
         1. The site plan will show how close a ground-mounted array is to the property lines or what structure a roof-mounted array is being placed on.
6. Familiarize yourself with the standards for solar installation in your city or county.
   1. Regardless of whether you acquire the permits or the contractor does, if some component of the installation is in violation of the community’s code of ordinances, it will fall back on the property owner to remedy the issue.
7. The homeowners’ Solar Rights Act protects homeowners rights to install solar panels if your home is subject to a homeowner’s association, common interest community association, or condominium unit owners' association.
   1. If your property is subject to one of the above associations, you may need to obtain an approval letter.

Find a solar installer

1. Obtain bids from several contractors.

Request quotes from at least three certified solar installers. Consider the price, equipment quality, warranties, and customer reviews.

2. Compare costs by calculating the price per watt. 

Here is an example of how to get an apples-to-apples comparison between two systems, a 5 kW and a 6 kW:

• System A: 5 kW (5,000 watts) system priced at $15,000
   $15,000 ÷ 5,000 watts = $3.00/watt
• System B: 6 kW (6,000 watts) system priced at $17,000
   $17,000 ÷ 6,000 watts = $2.83/watt

3. Schedule a professional site assessment

• This evaluates roof orientation, pitch, and structural integrity, and accounts for local weather patterns and shading issues.

Final steps

• Final Inspection: Your local building department must inspect the system to ensure it meets Illinois state electrical codes and safety standards.
• Utility Interconnection: Once approved, your installer will coordinate with the utility company to install a bi-directional meter (to measure electricity sent to and drawn from the grid) and finalize the connection to the grid.
• This process typically takes up to 10 business days after inspection approval

Solar system maintenance 

• Panels require minimal maintenance over their 20-30+ year lifespan. Panels are usually installed at an angle where snow will slide off naturally, but in areas with heavy snowfall, manual removal may be needed to maximize winter performance.
• Most modern systems include online monitoring tools that allow electricity production to be tracked in real-time.
• Routine inspections every 1-2 years by a qualified technician are recommended to check wiring, inverter performance, and panel condition. 

What if I move after installing solar panels?

Here are some questions to consider when moving after installing solar.

• Do you own or lease the system? Ownership usually makes resale easier, as you can include the system in the home sale. If you lease or have a Power Purchase Agreement, you’ll need to coordinate with the solar company, and potential buyers may need to qualify to take over the agreement.
• Is your new home suitable for solar? If you’re thinking about relocating the system, ask whether your new roof is structurally and directionally suitable. Also, consider whether the local climate and incentives support solar. In many cases, it’s more practical to leave the system in place.
• What are the costs and risks of moving the panels? Physically relocating a system can be costly and might damage your panels or your roof. Keep in mind that holes from mounting equipment may be visible after removal, or discolored shingles.
• Will solar help or hurt your home sale? A well-maintained solar system can be a selling point and may increase your home’s value. However, buyers unfamiliar with solar may have questions about maintenance, warranties, or agreements. Having clear documentation and recent performance data can help.