The Best Solar Companies in Illinois of 2023

Illinois may not be known for its sunshine, but that doesn’t mean homeowners can’t save big on energy bills by installing a solar system. These are the best solar companies in Illinois for homeowners ready to make the switch.

By Sabrina Serani | Published Jun 21, 2023 12:04 PM

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The Best Solar Companies in Illinois Options


Switching to solar has a medley of benefits for homeowners and the environment—even in states such as Illinois that have less than 200 days of sun on average per year. This is because solar panels keep producing energy even when there’s cloud cover. By installing a solar array, Illinois residents can benefit from lower energy costs and reduce fossil fuel dependency. But solar is a fast-growing industry, and it’s smart for homeowners to research their options before signing a contract with a solar company in the Land of Lincoln. Here, we’ve compiled a list of the best solar companies in Illinois, along with some tips to help Illinois homeowners navigate the solar installation process.

  1. BEST OVERALL: SunPower
  2. RUNNER-UP: ADT Solar
  5. ALSO CONSIDER: StraightUp Solar
The Best Solar Companies in Illinois Options


What to Consider When Choosing One of the Best Solar Companies in Illinois

There are many factors to ponder when contemplating the installation of solar panels and searching for a top-notch solar company in Illinois to undertake the task. In this context, we have emphasized several paramount aspects that homeowners will want to take into account throughout this endeavor.

Home Location and Roof Type

The primary consideration for homeowners thinking about installing a solar array is their home—specifically, the direction the home faces, the roof angle, and the roof material.

In the northern hemisphere, it’s optimal to install solar panels on a south-facing roof. Because of Earth’s tilt, the sun travels in a slightly southern path—not straight across the sky. A south-facing roof ensures that a home receives the maximum amount of sunlight year-round. Southeast and southwest are the next best possibilities for a home’s orientation, as those roofs will still capture some of the southerly path of the sun. However, it’s possible to mount panels on roofs facing other directions; the power generation may just not be as optimal.

A 30- to 45-degree mounting angle ensures optimal sun exposure for solar panels. If a roof is flat, solar panels are typically mounted on tilting brackets to bring the panels up to 30 degrees. Extremely steep roofs can still have solar panels mounted, but it may not be possible for the panels to capture enough sunlight for the home to become energy independent.

It’s possible to mount a solar array on any kind of roof material—but some types may be easier to work with than others. Composite shingles are durable and hold up well to the installation process, and standing seams on metal roofs minimize the amount of drilling and modifications needed. Tile roofs can present a bit more of a challenge; since each tile has some irregularities, it may take more time (and cost more in labor) to install a solar array.

Type of Panels and Efficiency

The two main types of solar panels used for powering homes are monocrystalline and polycrystalline. Monocrystalline is more efficient (meaning it is able to turn more sunlight into usable electricity) but also more expensive, while polycrystalline is more affordable but compromises power production. It’s possible to tell the difference between the two by the color: Monocrystalline panels will be pure black, while polycrystalline panels appear blue. The type of panel a homeowner opts for will ultimately come down to their budget and power-production goals. An experienced Illinois solar installer can help a homeowner make the right decision.

One distinction to note is that the efficiency of an individual solar cell is not the same as the efficiency of a panel. A solar cell is part of a solar panel, and a cell could have over 40 percent efficiency on its own. However, entire panels will have lower efficiency. Monocrystalline panels typically max out around 23 percent efficiency, while polycrystalline panels reach an efficiency of about 16 percent. Researchers at the National Renewable Energy Laboratory have created a solar panel with almost 40 percent efficiency, but this technology isn’t yet ready for the public.

There’s another type of panel to note: thin film. These panels are (as the name suggests) thin, flexible, and lightweight, but they’re even less efficient than polycrystalline. Thin-film solar panels also have the shortest lifespan of 10 to 20 years compared to the 25-year-plus lifespan of their monocrystalline and polycrystalline counterparts. Because of their lower efficiency, more would be required to power a home fully—and most roofs won’t have the space to accommodate the number of panels required. However, thin-film panels can be used as supplemental power production and are beneficial for homes that have unusually shaped roofs that may not be suitable for traditional panels.

On-Grid vs. Off-Grid

Another decision that homeowners have to consider when installing a solar system is whether or not they want the home to be connected to the local power grid. A home with a solar panel array still connected to the municipal grid is called on-grid or grid-tied. If it’s cloudy and the solar system can’t produce enough electricity to power the home fully, a grid-tied home can still pull power from the grid. However, if there’s a local power outage, the home can’t rely on its solar array—a grid-tied home will also experience an outage. This is a safety precaution so that electricity is not flowing into lines that utility technicians may be working on.

Off-grid homes are completely energy independent, meaning they’re responsible for generating all the power the home needs. Off-grid homes often rely on solar batteries to store excess energy and power the home during the night or when there’s cloud cover. Off-grid homes can still have power if there’s a local outage. However, the home will be without power if the battery backups are depleted and the panels can’t produce any electricity.

Some regions and homes are better suited for off-grid solar systems than others, and an experienced installer can help homeowners make the decision.

Financing, Rebates, and Tax Incentives

The average cost to install a solar system in Illinois is about $16,000, and not every homeowner has that lump sum of money readily available. The financing options available to a homeowner will, in part, depend on where they live. In Illinois, homeowners have three financing options: a solar loan, a solar lease, or a power purchase agreement (PPA).

  • Solar loan: A homeowner borrows money from a lender or solar developer to purchase and install a solar system. In this situation, the homeowner owns the system, but it’s still subject to a lien or lender security interest. Homeowners with one of the best solar panel loans are eligible for tax incentives. However, not every homeowner will be eligible for a loan, and the homeowner is totally responsible for any maintenance costs.
  • Solar lease: A homeowner enters into a contract with a solar leasing company or developer. The homeowner makes regular payments and, in exchange, receives the energy the panels produce. Some contracts may require the homeowner to make a down payment. At first, the lease payments are often less than the value of the power being generated. However, payments for solar leases often escalate as time goes on. Eventually, the cost of the payment may be greater than the value of the power being produced. This option is attractive because there’s little to no up-front cost and the solar developer is in charge of any maintenance. However, homeowners may not be eligible for tax incentives, and there may be restrictions if a homeowner wants to add new construction (e.g., if the homeowner wanted to build a new addition that would block the panels from getting light).
  • Power purchase agreement (PPA): A PPA is similar to a solar lease. The solar company buys and installs the solar system, and the homeowner pays the company per kilowatt-hour (kWh) for the energy that’s produced. A homeowner typically pays less for the solar energy than they would buying the equivalent amount from the utility. However, the PPA rate generally increases over time. The advantages and disadvantages are similar to those of a solar lease.

There are no state solar incentives available in Illinois, but homeowners can still access the federal investment tax credit (ITC). For solar systems installed between 2023 and 2032, homeowners are eligible for a 30 percent tax credit. So, for example, if the solar system cost $10,000, the homeowner can obtain a $3,000 reduction on their federal income taxes. Solar leases and PPAs do not qualify for this credit.


Like traditional home improvement projects, solar arrays often come with a labor warranty to cover any issues resulting from the actual installation work. These labor warranties can last anywhere from 10 to 25 years. The panels themselves will also come with equipment warranties, often for about 25 years. Finally, many solar companies in Illinois offer performance warranties, wherein the solar system is guaranteed to output a certain level of energy for the guarantee term, often 20 to 25 years.

Customer Support

Top-rated solar companies with multiple avenues of customer support often have better customer experience rates, as it’s easier to get in touch with a representative when there are questions or issues. Offering customer support over the phone is standard for many of these companies, but sometimes it can be difficult to get a real person on the line in a timely fashion. Some solar customers may prefer to email the company so there is a digital paper trail of conversation.

Our Top Picks

We’ve evaluated dozens of professional installers for solar in Illinois to find the ones that are the best of the Prairie State. We consider these five to be the top solar companies in Illinois.

Best Overall

The Best Solar Companies in Illinois Option SunPower

Why It Made the Cut: SunPower stands as one of the largest solar installation companies in the nation, and its reputation is well deserved. This company manufactures some of the finest solar panels available in the market.

For homeowners seeking the most effective solar panels, SunPower is highly recommended. The company’s exclusive Maxeon monocrystalline panels boast an impressive efficiency rating of 22.8 percent, which happens to be the highest in the market. These panels hold the prestigious Cradle to Cradle certification, demonstrating SunPower’s commitment to sustainability by considering factors such as material health, product circularity, social fairness, water and soil stewardship, as well as clean air and climate protection.

To assist homeowners in visualizing how a solar array would appear on their residences, SunPower offers an interactive design-studio feature. The panels themselves are streamlined and inconspicuous, thanks to the integration of microinverters that do not contribute any additional visual bulk. Interested customers can easily contact the company via telephone.



  • Type of panels: SunPower Maxeon monocrystalline
  • Payment options: Buy, finance, lease
  • Guarantee: 25-year complete-system and labor warranty
  • Customer support: Phone


  • High 22.8 percent efficiency rate
  • Generous 25-year complete system and labor warranty
  • Cradle to Cradle–certified equipment
  • Interactive online design-studio feature
  • Sleek solar panel design with built-in microinverters


  • Customer service only available by phone


The Best Solar Companies in Illinois Option ADT Solar

Why It Made the Cut: ADT Solar provides the dependability associated with its parent security company, ensuring round-the-clock monitoring and an assurance of power production.

Recognized primarily as a security company, ADT expanded its operations into the solar industry through the acquisition of Sunpro Solar in 2021. ADT Solar presents a remarkable power-production guarantee that spans 25 years, safeguarding the solar system’s ability to consistently generate energy throughout this extensive period. The inclusion of 24/7 solar monitoring is instrumental in promptly notifying homeowners in the event of any system malfunctions, preventing surprises when the electricity bill arrives and revealing a lack of power generation.

ADT Solar installs high-quality panel brands such as Q Cells, Silfab, and Canadian Solar, ensuring the utilization of top-tier components. Furthermore, the company offers energy storage solutions, although specific details regarding panel and battery warranties can be obtained by contacting a representative. In situations where roof repairs are necessary prior to panel installation, ADT Solar’s affiliated company, Buildpro, possesses the expertise to handle such tasks.



  • Type of panels: Q Cells, Silfab, Canadian Solar
  • Payment options: Buy, finance, lease
  • Guarantee: 25-year power-production guarantee
  • Customer support: Phone, email


  • Generous 25-year power-production guarantee
  • 24/7 solar monitoring
  • Additional roofing repair services available


  • Warranty information on battery not readily available online

Best Bang for the Buck

The Best Solar Companies in Illinois Option Tesla

Why It Made the Cut: Tesla may not immediately be associated with affordability, but the company’s price-match guarantee challenges that notion.

Renowned for its groundbreaking and visually appealing sustainable technology, Tesla also excels in the realm of solar solutions. Customers have the option to purchase or finance conventional solar panels or opt for the sleeker and more compact solar tiles, which are seamlessly integrated into the roof like shingles. These proprietary solar tiles are particularly suitable for individuals who prioritize both solar energy adoption and aesthetic appeal. To obtain a quick and convenient price estimate, customers can utilize Tesla’s online instant quote feature. Furthermore, Tesla extends a price-match guarantee on a per-watt basis, assuring customers that they will receive a competitive offer aligned with recent quotes for comparable solar systems.



  • Type of panels: Tesla monocrystalline, Tesla solar roof tiles
  • Payment options: Buy, finance
  • Guarantee: 25-year performance guarantee, 10-year comprehensive warranty
  • Customer support: Live chat


  • Traditional solar panels and sleek solar tiles available
  • Generous price-match guarantee
  • Instant online quotes available


  • No solar lease option

Best Financing Options

The Best Solar Companies in Illinois Option Blue Raven Solar

Why It Made the Cut: Blue Raven Solar’s BluePower Plus+ financing presents an attractive opportunity for customers, combining the advantages of solar panel leasing with the long-term returns of ownership.

Although the company does not offer a stand-alone lease option, selecting this financing plan brings noteworthy benefits. After the initial installation, customers can enjoy 18 months of free solar power, resulting in potential savings amounting to thousands of dollars. Blue Raven Solar emphasizes that this financing plan enables customers to cover 33 percent or more of their system cost without any up-front expenses.

Moreover, Blue Raven Solar offers the exclusive Smart Start program. Through this program, customers can extend the promotional period of 18 months by an additional 42 months, maintaining consistent monthly payments for a full 5 years. This allows homeowners to embrace solar panel installation while benefiting from a guaranteed low monthly payment.

The company provides customers with a complimentary energy-saving kit, comprising a smart thermostat and an LED light package. This kit aids in reducing annual heating and cooling costs by an average of 20 percent, contributing to enhanced energy efficiency for homeowners.



  • Type of panels: Monocrystalline (various manufacturers)
  • Payment options: Buy, finance
  • Guarantee: 25-year manufacturer warranty, 10-year labor warranty
  • Customer support: Phone, email


  • Flexible and relatively affordable BluePower Plus+ financing option
  • Money-saving Smart Start program available
  • Complimentary energy-saving kit


  • No solar lease option

Also Consider

The Best Solar Companies in Illinois Option StraightUp Solar

Why It Made the Cut: Customers looking for a standout local solar installer will appreciate StraightUp Solar’s commitment to sustainable building practices and convenient repair and maintenance offerings.

StraightUp Solar operates in Illinois and Missouri and installs high-quality Tier 1 panels, and customers have the option to purchase or finance their systems. The company also performs any repairs or ongoing maintenance the solar array may require after installation. This is a convenience to homeowners since they won’t have to find a separate company to perform these tasks. StraightUp Solar also holds a Pearl Certification; this certification gives homeowners peace of mind that their solar installation is a solid investment and that the company has a commitment to high-quality and energy-efficient building practices.



  • Type of panels: Unspecified Tier 1 panels
  • Payment options: Buy, finance
  • Guarantees: 10-year labor and power production warranty
  • Customer support: Phone, email


  • Solar repairs and maintenance offered
  • Pearl-certified member with commitment to green building practices


  • No solar lease option

Our Verdict

We chose SunPower as our Best Overall pick because of its high-efficiency solar panels, Cradle to Cradle certification indicating environmental responsibility, and user-friendly online design studio. ADT Solar took the Runner-Up spot thanks to its impressive 25-year power-production guarantee and roofing services through Buildpro.

How We Chose the Best Solar Companies in Illinois

In order to identify the top residential solar companies in Illinois, we conducted a comprehensive analysis based on various criteria. Initially, we assessed each company to ascertain the extent and nature of guarantees or warranties provided. Furthermore, we thoroughly examined the available payment options, assessing the companies that offered purchasing, financing, and leasing alternatives. Another crucial aspect considered was the quality of customer service, particularly the communication channels available for customers to address any inquiries or issues regarding their solar systems. Lastly, we looked for distinctive features that set a solar company apart from its competitors, including innovative financing choices, convenient online quoting systems, and supplementary services offered.

Before You Work With One of the Best Solar Companies in Illinois

Before finalizing a contract with a solar energy company, it is imperative for homeowners in Illinois to conduct thorough research and identify a company that aligns with their requirements. While many customers are likely to discover suitable options among the featured best solar companies in Illinois, others may need to explore beyond this list to find their ideal match.

Regardless of whether a homeowner chooses a company from the provided selection or opts for a different company altogether, it is crucial to ensure a comprehensive understanding of the contract agreement. Homeowners will want to carefully review the contract to confirm that the arrangement includes an adequate number of panels arranged in a manner that meets their energy needs, fits within their budget, and adheres to their preferred installation timeline. It is also advisable for homeowners to seek clarification regarding the functioning of the solar panels, contingency plans in case of system overproduction, and the optimal financing alternatives available. Reputable solar companies will readily address any inquiries posed by customers to the best of their abilities, demonstrating their commitment to exceptional customer service.

Cost of Working With One of the Best Solar Companies in Illinois

While the exact cost of solar panels for homes will vary from customer to customer, Illinois homeowners can expect to pay an average of $3.20 per watt of power. This means a homeowner will pay around $16,000 to install a 5-kilowatt solar system on their home. That cost can rise to an average of $32,000 for a larger 10-kilowatt system. However, some of these costs can be offset by taking advantage of available tax credits. The federal government offers a residential clean-energy credit for homeowners who install solar panels. This can decrease the total cost of the system by up to 30 percent. With the full tax credit applied, this can decrease the cost of a 5-kilowatt system to $11,840 and the cost of a 10-kilowatt system to $23,680.

The Advantages of Working With One of the Best Solar Companies in Illinois

The best solar companies in Illinois offer various benefits to customers who opt to work with them. Homeowners can often choose from various financing or leasing options, which can make solar panel installation more accessible. They may also be able to get a free quote online, which can help them gauge their approximate cost to install solar panels on their home. In addition, many of the best Illinois solar companies offer the following advantages:

  • Robust guarantees on equipment and labor;
  • 24/7 solar monitoring through a user-friendly app; and
  • High-quality solar panels from reputable solar manufacturers.


The decision to install solar panels can be a tough one, since the cost is high and customers might wonder whether the project is worth it. The following frequently asked questions and their answers can help Illinois homeowners get a better idea of the benefits of solar panels.

Q. Is Illinois a good state for solar?

Due to the rising cost of electricity in the state, it can be a good idea to go solar in Illinois. There are many advantages to going solar, including saving money on energy bills and reducing fossil fuel consumption.

Q. What is the average cost of solar in Illinois?

The average cost per kilowatt is $3.20, making the average cost for a 5 kW system $16,000. While this may seem like a costly investment, the savings on energy bills will likely make a solar installation worth it; Illinois Solar for All estimates that homeowners save an average of $1,000 per year on energy bills with a solar array.

Q. Is solar tax-exempt in Illinois?

Solar is not exempt from tax in Illinois.

Q. Does Illinois offer free solar panels?

No, there is no program for free solar in Illinois.

Q. Does Illinois buy back solar energy?

Yes, there is net metering in Illinois where the utility company will buy excess energy produced.

Q. How long do solar panels last in Illinois?

In general, solar panels last about 25 years.

Sources: Current Results, EnergySage