Solar is a strong investment on the right roof, but several efficiency measures pay back faster. Cutting demand first also shrinks the array you need, which lowers capex, eases the DNO conversation and improves the payback on everything that follows.
Warehouse and production lighting often runs 60+ hours a week. LEDs with daylight and occupancy control typically cut lighting load by 50 - 70%.
Leaks commonly waste 20 - 30% of compressor output. An ultrasonic survey and a fix programme is one of the cheapest kWh reductions available.
Heating and cooling fighting each other, or running out of hours, is extremely common. Controls and BMS tuning cost little and save immediately.
Variable speed drives on fans and pumps cut consumption sharply where load varies. Replacing oversized fixed-speed motors compounds the saving.
Door seals, strip curtains, defrost scheduling and head pressure control deliver large savings on cold storage sites before any generation is added.
Twelve months of half-hourly data exposes overnight baseload, weekend drift and demand peaks. It is the cheapest diagnostic you can run.
It reduces the size of the array, not the quality of the investment. A smaller system on a corrected load self-consumes a higher proportion of what it generates, which is exactly what drives payback. You spend less capital and keep a similar return.
Payback ranges here are typical UK commercial figures for planning purposes. Actual results depend on operating hours, tariff and existing equipment condition.