A Base Case for Solar Panels on Industrial & Logistics Units in the UK

One of the most practical applications of solar energy lies in harnessing the vast roof space of large warehouse buildings. Across the UK, there are over 2.24 billion square feet of warehouse space in units over 50,000 square feet — a significant real estate footprint that can be utilised to host solar generation.

The typical 300-watt solar panel, which represents a mid-standard panel on the market, occupies around 16.5 square feet of roof space. In most industrial settings, around 75% of the roof area is usable for solar panel installation, once you account for spacing, equipment, and safety margins. Based on this, you can fit roughly 45 panels per 1,000 square feet of usable roof. Applied at scale, this translates to an enormous number of solar panels across the UK’s logistics property stock.

To understand the energy potential, we can attain a conservative estimate with the following formula for daily output: Daily kilowatt-hour (kWh) production equals the panel wattage multiplied by the location’s peak sun hours, multiplied by a 0.75 efficiency factor (to account for losses in the system), and then divided by 1,000 to convert from watt-hours to kilowatt-hours. In the UK, a realistic average for peak sun hours is about 3 per day, given the country’s latitude and weather conditions. Applying this to a 300-watt panel: 300 × 3 × 0.75 / 1000 = 0.675 kWh per panel, per day.

If we scale this calculation across the total usable roof space (75% of the 2.24 billion sq ft total), we end up with approximately 1.68 billion square feet of solar-ready roof area. Dividing this by the 16.5 sq ft required per panel gives us just over 101 million panels. If each of these produces 0.675 kWh per day, then the total daily energy generation potential is around 68.3 million kilowatt-hours. This is a remarkable amount of clean electricity generated using existing commercial rooftops.

This kind of solar deployment carries wide-reaching benefits. From a financial perspective, it can significantly reduce operational energy costs for occupiers, or generate additional income through feed-in tariffs or power purchase agreements. From an environmental perspective, it drastically cuts carbon emissions, helping landlords and tenants meet their net-zero and ESG commitments. And strategically, it enhances energy resilience, reducing reliance on the grid and supporting a more distributed and secure energy system. Pair renewable self-generation with on-site battery storage, energy resilience is improved even further, and ROI's can be much shorter.

The United Kingdoms Warehousing Association’s Clare Bottle supports the rise of solar panels by highlighting a crucial message: warehouses are not just the backbone of the UK economy, driving growth, serving fast-changing consumer needs and offering quality employment nationwide; they’re also an overlooked opportunity in the shift to renewable energy.

UKWA’s 2022 research revealed a striking fact: ‘installing solar panels on just a portion of existing warehouse rooftops could double the UK’s solar capacity’. Since then, the number of warehouses has only increased, and so has the demand for electricity, fuelled primarily by the rise of robotics, automation, EV fleets, battery-powered machinery and Data Centres. Generating clean energy directly at the point of use will play an essential part in meeting the rising demand. Yet, despite the potential, only around 5% of warehouses currently have solar installed, largely due to the difficulties in delivering rooftop solar arrays. 

In conclusion, this base case illustrates the vast, underutilised potential for solar power generation across the UK’s industrial and logistics property sector. Even with conservative assumptions on sun exposure and panel density, the numbers point to a meaningful opportunity to decarbonise one of the country’s most space-rich asset classes. That said rooftop solar is not always deliverable and Ground Mounted solar (amongst other technologies) provide equally attractive benefits.