The cost of a complete commercial solar installation is usually $1.70 to $3.00 per watt before incentives. For a U.S. business, that means a small or complex rooftop project may cost more, while a large, straightforward installation may cost less.
| System size | Typical installed cost before incentives |
|---|---|
| 50 kW | $125,000 to $175,000 |
| 100 kW | $210,000 to $300,000 |
| 250 kW | $425,000 to $600,000 |
| 500 kW | $750,000 to $1.05 million |
| 1 MW | $1.3 million to $1.9 million |
These budgetary estimates cover a complete photovoltaic system, including panels, inverters, racking, engineering, installation and electrical work. They exclude batteries, unusual structural repairs, financing costs and tax incentives.
The latest publicly reported U.S. commercial solar system price was $1.77 per watt in the second quarter of 2026. The U.S. Department of Energy's 2025 benchmark for a 250 kW commercial PV system was $1.95 per watt without battery storage.
What Does a Commercial Solar System Cost by Size?
Commercial solar costs by size generally fall as the system gets larger. Engineering, permitting, mobilization and other fixed costs are spread across more generating capacity.
| Commercial project | Planning price per watt | Approximate total cost |
|---|---|---|
| Small rooftop, 25 to 50 kW | $2.50 to $3.50 | $62,500 to $175,000 |
| Medium rooftop, 100 kW | $2.10 to $3.00 | $210,000 to $300,000 |
| Warehouse or school, 250 kW | $1.70 to $2.40 | $425,000 to $600,000 |
| Large commercial rooftop, 500 kW | $1.50 to $2.10 | $750,000 to $1.05 million |
| Large commercial or industrial, 1 MW | $1.30 to $1.90 | $1.3 million to $1.9 million |
These are planning ranges, not fixed quotes. Local labor rates, roof conditions, utility requirements and equipment availability can change the final price.
Does the Price Include Solar Panels Only?
A commercial solar quote usually covers the installed PV system, not the panels alone. Depending on the project, the quote may include:
- Solar panels or modules
- String or central inverters
- Racking and roof attachments
- Electrical conduit, wiring and switchgear
- Engineering and system design
- Structural assessment
- Permits and inspections
- Utility interconnection
- Construction labor
- Monitoring equipment
- Commissioning and warranties
For comparison, distributed-generation module prices were approximately $0.37 per watt in Q2 2026. That figure excludes most project-level installation costs.
How Much Does Commercial Solar Cost With Battery Storage?
Battery storage can add several hundred thousand dollars to a medium-sized commercial project. The final cost depends on the battery's energy capacity, power rating, controls and installation requirements.
The Department of Energy's 2025 benchmark compares a representative 250 kW commercial rooftop system with and without storage:
| System | Benchmark price |
|---|---|
| 250 kW commercial PV without storage | $1.95 per watt |
| 250 kW PV plus 500 kWh battery storage | $2.96 per watt |
Under those assumptions, the solar-only system costs approximately $487,500. The solar-plus-storage system costs approximately $740,000. The DOE model represents a specific school rooftop design using domestic-content equipment, so actual project prices will vary.
Battery storage may help a business:
- Reduce demand charges
- Shift solar energy into evening hours
- Provide backup power
- Reduce exposure to time-of-use electricity rates
- Participate in utility or grid programs
A battery is not automatically a good investment. The financial case depends on the utility tariff and the business's hourly electricity use.
What Factors Affect Commercial Solar Installation Cost?
System Size
Larger systems usually have a lower cost per watt. A 50 kW project may carry high design and permitting costs relative to its size. A 1 MW project can spread those costs across more capacity and use larger equipment more efficiently.
Roof Condition and Structure
A roof that needs replacement before installation can add substantially to the project cost. Structural reinforcement may also be necessary for an older building or a roof with limited load capacity.
A sound, flat commercial roof is usually simpler to work on than a steep, irregular or heavily obstructed roof.
Electrical Service and Interconnection
The utility may require upgrades to transformers, switchgear, protection equipment or service capacity. Interconnection studies, trenching and off-site utility work can add costs that are not apparent from the panel count alone.
Location and Labor
Commercial solar prices vary by state and metro area. Labor, permitting, inspection requirements, prevailing-wage rules, freight, local electrical standards and utility procedures all affect the final quote.
Recent U.S. price increases have been linked to higher structural, electrical, transportation and EPC costs, even as module prices declined.
Equipment and Sourcing
Domestic-content requirements, tariffs, inverter availability and the selected racking or module technology can change the installed price. A lower panel price does not always produce a lower total project cost if the equipment increases engineering, freight or installation work.
Rooftop, Ground-Mount or Carport Design
- Rooftop systems use existing building space but may require roof work or structural upgrades.
- Ground-mounted systems can be easier to orient and maintain but require land, foundations, trenching and civil work.
- Solar carports generate electricity while covering parking spaces, but they usually have higher structural costs than rooftop systems.
Are Commercial Solar Tax Incentives Included in the Cost?
The prices above are before incentives.
As of September 25, 2026, the federal Clean Electricity Investment Credit under Section 48E has a 6% base credit. The credit can increase to 30% when prevailing-wage and registered-apprenticeship requirements are met. Additional bonus amounts may apply for qualifying domestic content, energy-community locations or other eligible conditions.
Federal timing rules also affect eligibility. IRS guidance states that the Section 48E credit termination provisions apply to applicable solar facilities placed in service after December 31, 2027, when construction begins after July 4, 2026. A tax professional should confirm eligibility before the business reduces its expected project cost.
State incentives, utility rebates, accelerated depreciation and transferable tax credits may also affect the economics. Their availability depends on the business location, ownership structure and project eligibility.
What Should a Commercial Solar Quote Include?
An apples-to-apples commercial solar quote should show:
- System size in kW DC and kW AC
- Installed cost per watt
- Total project price before incentives
- Panel, inverter and racking specifications
- Engineering, permitting and interconnection costs
- Roof repairs or structural work included or excluded
- Battery capacity and controls, if applicable
- Operations and maintenance costs
- Production estimate and assumptions
- Equipment, workmanship and roof warranties
- Financing rate, lease payment or PPA price
- Change-order terms and expected completion date
The most useful starting comparison is the total installed cost divided by system capacity. Also compare the expected annual electricity production and the utility rate the system will replace.
The panel brand matters, but it does not determine the project's value on its own.
Bottom Line
Commercial solar pricing is a project budget, not a panel price. Start with the installed cost per watt, then account for roof work, interconnection, labor, equipment, storage and incentives.
Before signing, obtain at least three itemized proposals and confirm what each one includes.