Phoenix Journal · Energy & Efficiency
Not the brochure number - the real one. Why self-consumption decides the return, how to size a system, when a battery is worth it, and the tax relief that changes the sums.
Solar and storage
Solar gets sold to hospitality operators with a big round savings figure and a short payback. The honest version is more useful: whether panels pay on your site turns almost entirely on how much of what they generate you actually use yourself - and that depends on when your kitchen is busy.
The physics is not in dispute and the technology works. What varies wildly, site to site, is the money. So rather than a brochure number, here are the four questions that decide whether solar and battery are worth it for a hospitality site, answered with 2026 figures.
The core question
Often yes, but for one specific reason. Every unit you generate and use on site displaces a grid unit you would have bought at roughly 25 to 27 pence. Every unit you export instead earns a Smart Export Guarantee rate of only around 8 to 12 pence. So a unit used on site is worth two to three times a unit exported - and self-consumption, not panel count, is what drives the return.
This is where hospitality has a genuine edge. A kitchen with a strong daytime load - a cafe, a lunch-led operation, a hotel with all-day covers - can use 70 to 90 percent of what its panels make without any battery at all, because demand naturally lines up with generation.
Sizing and storage
Size generation to roughly match what you consume across a year, then cap it at what the roof physically holds - about 6.5 square metres per kilowatt-peak. In 2026 a typical commercial rooftop installs at roughly £700 to £1,100 per kilowatt-peak, less per unit at larger scale, and generates around 950 kilowatt-hours per installed kilowatt-peak a year in central England. Oversizing just pushes more generation onto the export meter at the low rate, which lengthens payback.
Batteries earn their keep differently. A battery stores midday surplus for your evening service, lifting self-consumption toward 90 percent - exactly what an evening-led restaurant needs. Commercial storage runs around £200 to £450 per kilowatt-hour and cells typically need replacing at around year twelve, so it is a second investment layered on the first. If you already self-consume most of your generation because you are busy in daylight, a battery adds cost for modest gain; if you export a lot because your covers are in the evening, it is where the case gets interesting.
Two practical checks decide most borderline cases. First, get your installer to model against your actual half-hourly consumption rather than an annual bill estimate - the shape of your demand, not its total, is what sets self-consumption and therefore payback. Second, factor the roof itself: age, pitch, orientation and any shading, plus whether a structural survey will trigger remedial work before panels go on. A south-facing pitch at thirty to forty degrees yields best in the UK, while an east-west split flattens the generation curve, which can actually suit a kitchen that trades morning and evening.
Tax and export
Treat export as a bonus, never the business case. Export income at 8 to 12 pence is real but small next to the 25-pence-plus you save by self-consuming. Build the case on avoided purchase and let export sweeten it. Solar is also one lever among several - it pairs naturally with the measures in reducing a hospitality carbon footprint.
The tax side is where operators leave money behind. The Annual Investment Allowance lets a profitable business deduct 100 percent of qualifying solar spend in year one, up to a one-million-pound cap - so the effective cost is roughly 75 percent of the headline for a main-rate corporation-tax payer. One myth worth killing: full expensing does not apply to solar. Panels are special-rate plant, so above the cap you get a 50 percent first-year allowance, not 100. Rooftop solar is also exempt from business rates until 2035.
Questions
It can be, but the maths is tighter than for a daytime operation. Evening-led kitchens generate solar at midday and use it at night, so more is exported at the low Smart Export Guarantee rate. A battery, which stores midday surplus for evening service, is usually what makes the case work in that pattern.
For most installations, yes - it allows a 100 percent first-year deduction up to a one-million-pound cap. Above that cap solar gets a 50 percent first-year allowance rather than full expensing, because it is classed as special-rate plant. Confirm the current position with your accountant before you model it.
Typically four to seven years before tax relief, and often under four for a profitable business once the Annual Investment Allowance is applied. Self-consumption is the biggest single lever - a site that uses most of its generation on site pays back far faster than one that exports heavily.
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