Installing commercial solar PV is only the beginning of the business case. As explored in our earlier Commercial Solar PV Systems: What Energy Managers Should Compare buyer’s guide, businesses need to consider much more than how many panels can physically fit on a roof. Once a system is operational, another question becomes increasingly important: How much of the electricity being generated is the organisation actually using effectively?
Solar generation is not the same thing as solar value. Businesses can improve returns by matching electricity demand more closely with generation, monitoring performance, considering battery storage and understanding when consuming, storing or exporting solar electricity creates the greatest value.
Understand Your Solar Self-Consumption
A commercial PV system might generate electricity when a building needs it, when demand is low or when nobody is there at all.
Consider two organisations with identical solar arrays.
Business A consumes most generation on site during working hours.
Business B has relatively little daytime demand and exports much of its electricity.
The arrays may generate exactly the same number of kWh, but their financial performance can differ.
This makes self-consumption — the proportion of generated solar electricity used on site — an important metric.
Solar ROI Principle
Don’t only measure how much electricity the panels generate. Measure what happens to that electricity afterwards.
Compare Generation with Your Demand Profile
The starting point is understanding when electricity is being consumed.
Energy managers should compare solar generation with half-hourly or similarly detailed consumption data where available. Look for:
- Morning demand
- Daytime baseload
- Lunchtime peaks
- Afternoon demand
- Evening consumption
- Weekend usage
- Seasonal differences
A warehouse operating throughout daylight hours may naturally consume a high proportion of its solar generation.
An office with low weekend occupancy could export considerably more on Saturdays and Sundays.
Understanding these patterns reveals where optimisation opportunities exist.
Shift Flexible Loads into Solar Hours
Not all electricity consumption has to happen at a fixed time.
Some processes may be moved towards periods of strong solar generation without affecting operations.
Depending on the organisation, flexible loads might include:
- EV charging
- Water heating
- HVAC pre-heating or pre-cooling
- Battery charging
- Refrigeration processes
- Pumps
- Certain manufacturing processes
Rather than allowing solar electricity to leave the site while buying electricity back later, organisations may be able to move appropriate demand into the generation window.
Energy Management Insight
Sometimes the cheapest way to store solar energy is not to store it at all: it is to move electricity demand to the time the energy is being generated.
Monitor Whether the System Is Performing Properly
Optimisation depends on knowing what the PV system is actually doing.
Energy managers should monitor:
Generation: How much electricity is being produced?
Consumption: How much is being used on site?
Export: How much leaves the site?
Import: How much electricity is still being purchased?
Performance monitoring can also help identify underperforming panels, inverter issues or unexpected changes in output.
Providers including DCC Energy, Energy Efficient Solutions Group, Prolectric Services and Trident Utilities operate across different areas of commercial energy management, infrastructure and renewable-energy services where understanding generation alongside wider consumption can support better decision-making.
Consider Battery Storage
Battery storage can increase the flexibility of commercial solar PV.
Instead of immediately exporting surplus electricity, a battery can store some of that energy for use later.
For example:
12pm: PV generation exceeds site demand.
Battery charges.
5pm: Solar output falls while site demand remains high.
Battery discharges.
Potential applications include:
- Increasing solar self-consumption
- Reducing peak grid demand
- Supporting time-of-use optimisation
- Providing flexibility
- Supporting resilience in appropriately designed systems
Solutions from businesses such as Wattstor demonstrate how solar, storage and energy-management technologies can be combined to optimise when organisations generate, store, consume and trade electricity.
Wattstor – https://wattstor.com/
Don’t Assume Every Solar Project Needs a Battery
Battery storage can improve some solar projects significantly.
That does not mean every commercial PV installation needs one.
A site already consuming almost all its solar generation during the day may gain relatively little additional self-consumption from storage.
Energy managers should assess:
- Surplus solar generation
- Evening demand
- Electricity tariffs
- Peak demand
- Battery capacity
- Expected cycling
- Capital cost
- Battery lifetime
The question is therefore not:
“Should we add a battery?”
It is:
“What problem would the battery solve?”
Connect Solar with EV Charging
Fleet electrification can create a valuable new source of flexible daytime demand.
Where vehicles are parked at a workplace or depot during solar-generating hours, charging can potentially be aligned with PV output.
Instead of every vehicle immediately charging at maximum power when plugged in, smart charging can help schedule demand around:
- Vehicle departure requirements
- Solar availability
- Site electrical capacity
- Electricity tariffs
This can turn EV charging from an additional electrical load into part of the organisation’s wider energy-management strategy.
Use Building Controls to Increase Self-Consumption
Commercial buildings contain other flexible electrical loads.
HVAC is an obvious example.
Rather than waiting until a building becomes too warm and then cooling it when solar generation has fallen, an organisation may sometimes be able to use controls to pre-cool appropriate spaces while renewable electricity is abundant.
The same principle can apply to other controllable systems.
This requires careful operational planning (comfort, production and building requirements should always come first) but it illustrates an important shift:
Solar optimisation is not only about the solar system. It is about how the rest of the site responds to it.
Understand the Value of Export
Using solar electricity on site is not the only way it can create value.
Eligible generators in Great Britain can receive payments for electricity exported to the grid through the Smart Export Guarantee (SEG). Ofgem states that eligible solar PV installations up to 5MW can participate, subject to scheme requirements.
Ofgem – Smart Export Guarantee – https://www.ofgem.gov.uk/environmental-and-social-schemes/smart-export-guarantee-seg
Tariff rates, contract lengths and other terms vary between SEG providers, so businesses should understand the export arrangements available to them.
Energy managers should therefore compare the value of:
Consume now | Store for later | Export
The best option can change according to electricity prices, export arrangements, battery state and site demand.
Look at Solar as Part of a Wider Energy System
Commercial PV becomes more valuable when it is considered alongside the organisation’s other energy assets.
That might include:
- Battery storage
- EV charging
- Building management systems
- Heat pumps
- Energy monitoring
- Flexible loads
- Grid connection
Providers such as Egg, Two Blues Solar and Wattstor operate across combinations of solar, storage, EV infrastructure and energy optimisation.
The opportunity is to move from managing individual technologies towards coordinating them.
Review Performance After Installation
The assumptions used in a solar business case should not disappear into a spreadsheet once the project is commissioned.
Energy managers should periodically compare:
Forecast generation vs actual generation
Expected self-consumption vs actual self-consumption
Expected savings vs actual savings
Expected export vs actual export
If performance differs materially from the business case, investigate why.
Perhaps consumption patterns changed.
Perhaps generation is below expectations.
Or perhaps surplus generation reveals an opportunity for batteries, EV charging or load shifting that was not originally available.
A Practical Commercial Solar Optimisation Checklist
Energy managers should ask:
- How much electricity is the PV system generating?
- What proportion is consumed on site?
- When does surplus generation occur?
- Which loads could move into solar-generating hours?
- Is the system performing against forecast?
- Could EV charging absorb daytime generation?
- Would building controls provide additional flexibility?
- Is there enough surplus electricity to justify battery storage?
- What value can exported electricity generate?
- Can solar, storage and flexible loads be managed together?
- Are savings tracking against the original business case?
Frequently Asked Questions
What is solar self-consumption?
Solar self-consumption is the proportion of electricity generated by a PV system that is used directly by the organisation rather than exported.
Does battery storage improve commercial solar ROI?
It can, particularly where significant surplus solar generation occurs at times when site demand is low. The business case depends on load profile, tariffs, battery utilisation, capital cost and other factors.
Can businesses be paid for surplus solar electricity?
Eligible generators can receive payments for electricity exported to the grid through arrangements including the Smart Export Guarantee, subject to eligibility and supplier terms.
Can EV charging increase solar self-consumption?
Potentially. Where vehicles are available to charge during solar-generating hours, smart charging can help align electricity demand with on-site renewable generation.
Product Guide
DCC Energy
Energy business operating across commercial energy and renewable solutions, supporting organisations with their wider transition towards lower-carbon energy.
Website: https://www.dccenergy.com/
Egg
Provides renewable-energy technologies including commercial solar PV, battery storage and EV charging solutions.
Website: https://crackingenergy.com/
Energy Efficient Solutions Group
Supports organisations with energy-efficiency and renewable-energy projects, including commercial solar PV and related technologies.
Website: https://www.eesg.co.uk/
Prolectric Services
Renewable-energy technology specialist providing solar and battery-powered solutions for commercial and infrastructure applications.
Website: https://prolectric.co.uk/
Trident Utilities
Energy-management consultancy supporting businesses with procurement, energy data, sustainability and wider utility-management requirements.
Website: https://tridentutilities.co.uk/
Two Blues Solar
Commercial solar specialist supporting organisations with the development and delivery of solar PV projects.
Website: https://twobluessolar.com/
Wattstor Ltd
Energy-management technology provider combining battery storage, renewable generation and intelligent energy optimisation to help organisations manage distributed energy assets.
Website: https://wattstor.com/
From Solar Generation to Solar Value
The business case for commercial solar does not end when panels begin producing electricity.
The next stage is optimisation:
generate → consume → shift → store → export → measure
The right balance will differ from site to site.
For some organisations, the greatest opportunity may be shifting existing demand. For others, it could be EV charging, battery storage or better export arrangements.
The common objective is to make each kWh of solar generation work as effectively as possible.
The Energy Management Summit connects senior energy professionals with carefully selected suppliers through pre-arranged one-to-one meetings, providing an opportunity to explore commercial solar PV, battery storage, energy management and wider decarbonisation solutions.
Related Reading
This article follows our earlier Commercial Solar PV Systems: What Energy Managers Should Compare buyer’s guide, covering system sizing, site assessment, panel and inverter selection, warranties, monitoring, installation and supplier evaluation.
Together, the two articles move from designing and procuring the right commercial solar PV system to maximising the financial value of the electricity it generates.
Sources
- Ofgem – Smart Export Guarantee – https://www.ofgem.gov.uk/environmental-and-social-schemes/smart-export-guarantee-seg
- Ofgem – Smart Export Guarantee Supplier List – https://www.ofgem.gov.uk/guidance/smart-export-guarantee-supplier-list
- Ofgem – Guidance for Generators: Co-location of Electricity Storage – https://www.ofgem.gov.uk/guidance/guidance-generators-co-location-electricity-storage-and-hydrogen-production-under-ro-fit-rego-and-seg-version-62
- GOV.UK – Smart Export Guarantee – https://www.gov.uk/government/publications/smart-export-guarantee-seg-earn-money-for-exporting-the-renewable-electricity-you-have-generated
- Energy Saving Trust – Smart Export Guarantee Explained – https://energysavingtrust.org.uk/advice/smart-export-guarantee/
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