Introduction
For many organisations, investing in commercial ground mounted solar is no longer simply a sustainability initiative, it is a strategic infrastructure investment capable of reducing operating costs, improving cash flow and protecting against future electricity price increases.
Unlike many capital expenditure projects, a commercial ground mounted solar installation begins generating measurable financial returns from the day it is commissioned. Every unit of renewable electricity generated and consumed on site reduces the need to purchase electricity from the National Grid, creating immediate operational savings while supporting wider ESG and Net Zero objectives.
Because commercial ground mounted solar systems can be developed at larger scales than many rooftop installations, they often provide the lowest cost of generating renewable electricity. When designed as a private wire system to maximise on-site consumption, they can deliver exceptional long-term value and compare favourably with many traditional capital investments.
This lesson explains how Energy Gain develops a robust financial business case, enabling Finance Directors, Managing Directors and Boards to evaluate commercial ground mounted solar using recognised financial appraisal techniques.
Why Businesses Invest in Ground Mounted Solar
The financial benefits of commercial ground mounted solar extend far beyond reducing electricity bills.
Businesses typically invest to:
- Reduce operating costs.
- Improve long-term cash flow.
- Protect against electricity price volatility.
- Generate low-cost renewable electricity.
- Reduce Scope 2 carbon emissions.
- Improve ESG performance.
- Support Net Zero strategies.
- Increase energy resilience.
- Create a productive long-term business asset.
- Reduce dependence on imported electricity.
Unlike many infrastructure projects, the financial return is directly linked to an operational cost that most businesses already incur every day electricity.
Why Ground Mounted Solar Often Delivers the Lowest Cost of Renewable Electricity
Commercial ground mounted solar is frequently the most cost-effective form of commercial solar generation.
Unlike rooftop solar, there are no structural loading constraints or complex roof access requirements.
Unlike commercial solar canopies, there is no requirement for architectural steelwork, parking structures or extensive reinforced concrete foundations.
Ground mounted solar benefits from:
- Simpler construction methods.
- Larger uninterrupted array layouts.
- Efficient installation.
- Straightforward maintenance.
- Easier access for servicing.
- Scalable system design.
- Lower installation cost per kilowatt peak (kWp).
As system size increases, these efficiencies often reduce the overall cost of generation, resulting in a lower Levelised Cost of Energy (LCOE) than alternative commercial solar solutions.
System Type | Typical Capital Cost | Scalability | Typical LCOE | Maintenance Access |
Rooftop Solar | Low | Medium | Low | Moderate |
Ground Mounted Solar | Medium | Excellent | Lowest | Excellent |
Solar Canopy | High | Medium | Higher | Excellent |
While every project is unique, organisations with available land and high daytime electricity demand often achieve the strongest long-term financial performance from commercial ground mounted solar.
Understanding Electricity Demand
The financial performance of any commercial solar installation is determined by how the electricity generated is used.
Energy Gain begins every feasibility study by analysing:
- Half-hourly electricity consumption.
- Daily demand profile.
- Seasonal demand.
- Weekend operation.
- Existing renewable generation.
- Future electrical loads.
- Planned business expansion.
The objective is to maximise self-consumption rather than exporting electricity at lower export tariffs
EPC Insight
The most profitable commercial ground mounted solar installations are designed around the client’s electricity demand, not simply the amount of available land. Increasing system size beyond the site’s consumption profile may increase export volumes but reduce the overall return on investment.
Private Wire Solar
Private wire solar is one of the principal reasons commercial ground mounted solar delivers such strong financial returns.
Instead of exporting electricity to the National Grid, the electricity generated is supplied directly to the business through a dedicated electrical connection.
This enables organisations to offset electricity purchased at commercial retail rates rather than receiving lower export payments.
Private wire systems typically provide:
- Greater operational savings.
- Higher self-consumption.
- Reduced transmission losses.
- Improved return on investment.
- Greater energy security.
Battery Energy Storage
Battery Energy Storage Systems (BESS) can further improve the financial performance of a commercial ground mounted solar installation.
Stored renewable electricity can be used:
- During evening operations.
- During peak tariff periods.
- To support critical electrical loads.
- To optimise electricity imports.
- To support EV charging infrastructure.
Battery storage can also improve site resilience while reducing exposure to fluctuating electricity prices.
Electric Vehicle Charging
Many organisations are now integrating EV charging into commercial ground mounted solar projects.
As company vehicle fleets transition towards electric vehicles and employee charging demand increases, daytime electricity consumption naturally rises.
This enables a greater proportion of the renewable electricity generated to be consumed on site.
Benefits include:
- Increased self-consumption.
- Reduced grid imports.
- Additional operational savings.
- Future-proofed infrastructure.
- Reduced fleet operating costs.
Where businesses choose to charge for EV use, charging infrastructure may also generate an additional revenue stream.
Revenue from EV Charging
Commercial EV charging can strengthen the financial case by creating a secondary income stream.
Organisations may offer:
- Employee charging.
- Fleet charging.
- Visitor charging.
- Public charging.
Specialist Charge Point Management Operators (CPMOs) can administer:
- User registration.
- Billing.
- Payment collection.
- VAT administration.
- Customer support.
- Driver apps.
- Reporting.
Outsourcing these services reduces administrative burden while allowing businesses to benefit from additional charging revenue.
Project Insight - Maximising Return Through a Private Wire Ground Mounted Solar Extension
Goodwin Steel Castings – Steel Manufacturing 2 MWp
Following the successful installation of a commercial rooftop solar system, detailed energy monitoring confirmed that the client’s foundry continued to import significant amounts of electricity from the grid during daylight hours. With unused land available adjacent to the facility, Energy Gain worked collaboratively with the client to evaluate whether extending the project with a commercial ground mounted solar installation would strengthen the overall business case.
Using half-hourly electricity consumption data and advanced financial modelling, we demonstrated that a private wire ground mounted solar system could supply additional renewable electricity directly to the foundry, significantly reducing imported electricity while improving the overall return on investment. By maximising self-consumption rather than exporting energy to the grid, the client created a larger renewable energy asset that delivered greater long-term financial returns and enhanced energy resilience.
Understanding Financial Metrics
Every Energy Gain proposal includes recognised financial appraisal techniques.
Capital Investment (CAPEX)
The total investment required to design, engineer, procure, construct and commission the commercial ground mounted solar installation.
Annual Electricity Savings
The projected reduction in imported electricity based on the renewable electricity consumed on site.
Cash Flow
Annual cash flow modelling demonstrates how electricity savings accumulate throughout the operational life of the system.
Payback Period
The estimated period required for cumulative savings to recover the initial capital investment.
While widely used, payback should never be considered in isolation.
Net Present Value (NPV)
NPV measures the value created by the investment after considering the time value of money.
A positive NPV demonstrates that the project creates long-term shareholder value.
Internal Rate of Return (IRR)
IRR allows commercial ground mounted solar to be compared with other competing capital projects.
Many organisations use IRR when prioritising capital expenditure.
Levelised Cost of Energy (LCOE)
LCOE measures the average lifetime cost of generating electricity.
Commercial ground mounted solar frequently delivers the lowest LCOE because of:
- Efficient construction.
- Large-scale installations.
- Straightforward maintenance.
- Long operating life.
- High annual generation.
Sensitivity Analysis
Every financial model should consider uncertainty.
Energy Gain develops multiple scenarios to assess:
- Electricity inflation.
- Export tariffs.
- System degradation.
- Operating costs.
- Future demand growth.
This enables Boards to understand both opportunities and risks before approving investment.
Funding Options
Commercial ground mounted solar can be financed using several approaches.
Typical funding routes include:
- Outright purchase.
- Asset finance.
- Finance lease.
- Hire purchase.
- Power Purchase Agreements (PPAs).
Each option affects cash flow, ownership and accounting treatment differently.
Tax Considerations
Commercial solar investments may qualify for favourable tax treatment depending on prevailing legislation.
Finance teams should consider:
- Capital allowances.
- Corporation Tax.
- Plant and machinery treatment.
- VAT.
- Depreciation.
Professional tax advice should always be sought before making investment decisions.
The Cost of Doing Nothing
When evaluating commercial ground mounted solar, organisations should also consider the financial impact of delaying investment.
Continuing to rely solely on grid electricity may result in:
- Higher operating costs.
- Continued exposure to electricity price volatility.
- Missed opportunities to reduce carbon emissions.
- Increased pressure from customers and investors regarding ESG performance.
- Delayed progress towards Net Zero commitments.
The decision is often not simply whether to invest in commercial solar, but whether the long-term cost of inaction is greater than the cost of investing today.
EPC Insight
A commercial ground mounted solar installation should be evaluated over its full operational life rather than against a short-term payback target. When assessed using cash flow, Net Present Value (NPV), Internal Rate of Return (IRR) and Levelised Cost of Energy (LCOE), ground mounted solar often compares favourably with other infrastructure investments because it delivers predictable electricity savings for more than 30 years.
FAQ
Is ground mounted solar cheaper than rooftop solar?
Not necessarily in terms of total project cost, but it often has a lower cost per installed kilowatt and can deliver the lowest lifetime cost of renewable electricity where sufficient land is available.
Does battery storage improve ROI?
It can. Battery storage increases flexibility by storing excess solar generation for later use, particularly where electricity demand extends beyond daylight hours.
Can EV charging generate additional income?
Yes. Commercial EV charging can provide a secondary revenue stream while increasing on-site consumption of renewable electricity. Third-party charge point management providers can also manage billing and customer administration.
Should export income be the main objective?
Generally, no. Most commercial ground mounted solar systems achieve stronger financial returns by maximising self-consumption through private wire connections rather than relying on electricity exports.
Key Learning Points
After completing this lesson you should understand:
- Why commercial ground mounted solar often provides the lowest Levelised Cost of Energy (LCOE).
- How private wire systems maximise financial returns.
- The importance of analysing half-hourly electricity consumption.
- How battery storage and EV charging can strengthen the investment case.
- The financial metrics used by Finance Directors and Boards to assess commercial solar investments.
- Why the cost of doing nothing should form part of every business case.
Lesson Summaries:
- Lesson 1: What is commercial ground mounted solar?
- Lesson 2: Is your site suitable for ground mounted solar?
- Lesson 3: Building the financial business case
- Lesson 4: Engineering, construction, and grid connection
- Lesson 5: Operations, maintenance, and performance optimisation
Related Services:
Energy Gain ground mount service
Ground mount cost and savings calculator
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