Rising food and labour costs have put intense pressure on grocery margins. As a retailer that competes on price, our client must keep operational overheads low, and savings on energy are savings that can be passed directly to customers. A supermarket that stays open seven days a week, refrigerates thousands of products around the clock, and runs lighting, tills, and air conditioning has large fixed energy costs, whether sales are up or down.
Our client understands this better than most. The UK’s fourth-largest supermarket has committed to net-zero emissions by 2035, targeting a 90% absolute reduction in Scope 1 and 2 emissions against a 2019 baseline. It already purchases 100% renewable electricity through REGO certificates, but the company views on-site generation as a means to take firmer control of its energy sources while gaining greater transparency around performance data.
Carbon3 is part of making that happen. We are an approved supplier on our client’s national solar framework, which is an agreement that gives the retailer a single, reliable delivery partner for its nationwide rollout, and gives Carbon3 a long-term pipeline to plan and resource against.
The challenge
Many store roofs required structural or waterproofing remediation before solar could be installed safely. Our client also needed a rapid, scalable delivery model that could be deployed across dozens of stores without disrupting trading. Because their stores consume most of their energy during the day, solar would only be effective if it was integrated cleanly with existing electrical systems and optimised for high daytime self-consumption.
How Carbon3 delivered it
Carbon3 delivered a two-stage programme across our client’s estate. First, we carried out structural assessments and completed roof remedial and reinstatement works on eight sites, ensuring every roof met the correct load-bearing, safety, and waterproofing standards before any solar equipment was installed.
Once each roof met specification, our team progressed to installation across the remedial sites and an additional thirteen stores that required installation only.
We scheduled construction carefully to avoid disruption to shoppers and staff, coordinating with store operations teams so work happened during quieter periods or outside trading hours. We also produced detailed energy-yield models for each site, showing our client how much energy would be generated during peak daytime opening hours and ensuring strong payback from day one.
In total, Carbon3 has now completed solar installations across 24 stores, adding over 2,544kWp of new solar to the estate. A further 16 sites are in the pipeline.
The Whitehaven store
Whitehaven is a strong illustration of what a well-designed rooftop system delivers for a standard supermarket format. Carbon3 installed a 144.55kWp solar PV system, designed, surveyed, and commissioned end-to-end by Carbon3’s in-house team.
The store will now save over 31 tonnes of CO2 per year, and £34,000 in energy savings.
That £34,000 is the expected saving every year, from the point of commissioning. For a single store, that is a meaningful and recurring reduction in operating cost, and money that goes back into margin rather than to the grid.
The wider programme
Each installation can supply up to 30% of a store’s annual energy needs. Because their stores operate mainly during daylight hours, the majority of that solar energy is consumed on-site giving the maximum financial benefit, as very little is exported back to the grid. This directly reduces grid dependence at the times energy is most expensive.
Our client’s national real estate director Jonathan Neale has said the programme has expanded to cover more sites than originally planned, with ongoing investment making operations more resilient while continuing to deliver value for customers. All new store builds will also come fitted with solar as standard.
Why supermarkets continue to work with Carbon3
Carbon3 has proven we can safely prepare and upgrade retail roofs at scale, install large solar systems with minimal operational disruption, and deliver cost savings aligned with supermarket trading patterns. The integration of remedial works, solar design, and installation under one delivery model gives supermarkets a single partner for nationwide rollout without subcontractor chains, coordination overheads, and gaps between the survey and the system going live.
The feedback from site reflects that:
“This project has now been successfully completed, and that’s down to the effort, professionalism and teamwork shown by everyone on site. The quality of the finished store is a real credit to the Carbon3 engineers. It’s been great working alongside such a dedicated group that take immense pride in what they do. Thank you again for your contributions and for helping to deliver the project safely and to a high standard.”
— Owen, Site Manager.
Find out more about this case study and other work we’ve done for large retail clients by contacting us today.
