Why a Brewery's Refrigeration Load Makes Solar Pay

Solar does not pay at a brewery because the roof is big or the panels are cheap. It pays because of one continuous, unglamorous electrical load that runs while the sun is up: refrigeration. Understand how your glycol chilling behaves through the day and you understand exactly why on-site solar earns its keep, and why the export meter is almost a distraction.

Start with the split: solar answers your power bill, not your gas bill

Be honest with yourself before you cost a single panel. Roughly 70% of the energy a brewery consumes is thermal, the wort boil, the hot liquor tank, steam, and space heating. That is gas or oil, and solar PV cannot offset it directly. Only about 30% of your energy is electrical, and that is the part a rooftop array actually touches.

If that sounds like a reason not to bother, it is the opposite. The electrical 30% is metered at commercial power prices, and within it sits a load profile that lines up almost perfectly with when solar generates. That alignment is the entire economic case. (If you are still weighing the thermal question, the honest answer lives on our is solar worth it for a brewery page, including the surplus-to-immersion and heat-pump routes for chipping away at the 70%.)

Your electrical load, ranked

A working brewery’s electricity divides roughly like this:

• Refrigeration and glycol chilling, around 35%. The single biggest slice.
• Packaging (canning, kegging, bottling), around 25%.
• Compressed air, 15-25%.
• Pumps, 15-20%.
• Lighting, 8-12%.

Packaging, air and pumps are real loads, but they are episodic, they run on brew days and packaging days and then stop. Refrigeration is different in kind. It is the one load that does not switch off.

Refrigeration is a baseload, not a spike

The glycol loop never sleeps

During active fermentation, the glycol chiller holds your fermentation vessels at temperature 24 hours a day, seven days a week. Yeast throws off heat as it works; the chiller pulls it back out continuously to keep the FVs on their profile. Then add cold crashing, bright-tank and cellar temperatures, cold-liquor make-up, and taproom cellar cooling. None of it clocks off at 5pm.

That means your refrigeration draws power all day, every day you have beer fermenting, and critically, right through the middle of the day when a rooftop array is at full output. You are not trying to catch a brief lunchtime peak. You have a guaranteed, always-on electrical baseload sitting underneath your generation curve, ready to absorb whatever the panels produce.

This is why breweries routinely achieve 75-90% self-consumption, the share of generated electricity used on site rather than exported. Most commercial rooftops that run 9-to-5 dump a big slug of midday generation to the grid because nobody is using it. A brewery with fermenters full has a fridge running to swallow it.

Why a self-consumed unit is worth roughly twice an exported one

This is the number that changes how you think about the whole project.

When you use a solar kWh on site, you avoid buying that unit from your supplier. The DESNZ Q2 2026 non-domestic average import price is around 25p/kWh; large half-hourly-metered brewery sites typically sit lower, in the 15-24p/kWh band once you strip out standing charges. Either way, that is what a self-consumed unit is worth to you, the price you did not pay.

When you export a solar kWh instead, you earn a Smart Export Guarantee (SEG) tariff. SEG rates are supplier-set and currently sit in a 12-16p/kWh range, Octopus cut its rate to 12p on 1 March 2026, which tells you the direction of travel. You can read the mechanics on Ofgem’s Smart Export Guarantee pages.

So a unit consumed on site is worth roughly 1.6 to 2 times a unit exported. Refrigeration is what lets you land on the right side of that trade: because the glycol load guarantees a large daytime baseload, the great majority of your generation displaces expensive imports rather than trickling out to the grid at half the value. Self-consumption is not a nice-to-have, it is the mechanism that makes the payback work.

There is a grid dimension here too. A brewery array is always a G99 connection (you will be drawing well over 16A per phase on three-phase 415V), and where the local network operator limits your export capacity, a G100 export-limitation scheme keeps you compliant while you consume behind the meter. In other words, the design already nudges you toward using power on site rather than exporting it.

Size to the fridge, not to the roof

The temptation is to fill every square metre of roof. Resist it. The right size is the one your daytime baseload can actually absorb.

Useful planning figures for UK breweries:

• Electricity intensity: 8-16 kWh per hectolitre (nano and very small craft sites run higher, 15-20+).
• UK yield: about 850 kWh per kWp per year.
• Roof area: roughly 6 m² per kWp.

Typical system sizes track brewery scale: nano 6-30kW, craft micro 20-50kW, growing craft 50-200kW, regional 250-750kW, and national sites 1MW and up. The craft microbreweries profile shows how a smaller site’s numbers shake out.

An array sized so that your midday generation is mostly swallowed by the chiller, packaging and compressed air will beat a bigger array that spills half its output to the grid at SEG rates. If you want to push self-consumption higher still, and shift some daytime generation to cover overnight fermentation cooling, a battery is the tool, but note that refrigeration already does most of the heavy lifting before you spend a penny on storage. Model your own mix with the savings calculator.

Scheduling flexible loads into the midday window

Refrigeration is your fixed baseload. Everything else on the list, packaging runs, CIP cycles, compressed-air duty, pumping, cold-liquor make-up, is at least partly movable. That flexibility is free extra self-consumption if you plan around your generation.

Practical moves:

• Run canning, kegging and bottling in the 10am-4pm window wherever your schedule allows. Packaging is your second-biggest load; overlaying it on peak solar keeps those units behind the meter.
• Time CIP cycles for the middle of the day. Cleaning is power-hungry and rarely time-critical to the hour.
• Shift compressed-air-heavy tasks and cold-liquor make-up into daylight.
• Bias brew-day activity toward the sunniest hours when the brewhouse schedule gives you the choice.

The principle is simple: your fridge guarantees you a floor of daytime consumption, and scheduling the flexible loads on top of it lets you soak up the surplus that would otherwise export cheaply. Breweries that do both routinely land near the top of the 75-90% self-consumption range.

What it costs, and what it pays back

Installed cost for commercial rooftop solar runs about £550-1,100 per kWp, smaller systems at the top of that range, larger arrays at the bottom. With brewery-grade self-consumption, payback typically lands at 4-7 years (nanobreweries at the longer end, regional sites the shortest, because scale drives both cost per kWp down and self-consumption up).

A few things sharpen the numbers, covered in full on our cost and grants and funding pages:

• Capital allowances. Solar PV is special-rate plant under HMRC’s capital allowances rules. It qualifies for the Annual Investment Allowance, 100% relief in year one up to £1m, but it is excluded from full expensing and the new 40% main-rate first-year allowance, so ignore any quote that claims those apply.
• VAT. Commercial solar carries 20% VAT, which is reclaimable if you are VAT-registered. The 0% rate is domestic-only, it does not apply to a brewery.
• Business rates. On-site solar and storage are exempt from business rates in England until 31 March 2035 (this is England-specific; Wales and Scotland differ).
• The CCA angle. The brewing-sector Climate Change Agreement can bring meaningful Climate Change Levy relief, and self-generated on-site solar sits outside CCL entirely. Larger breweries generally qualify comfortably; many small craft sites may not meet the energy-intensity threshold, so check eligibility with the BBPA rather than assuming it.

Common questions

Does solar cut my gas or thermal bill?

No, not directly. Solar PV offsets electricity, and around 70% of your energy is thermal (the boil, the HLT, steam). Panels attack the electrical 30%. You can route summer PV surplus into an immersion in the hot liquor tank, or pair with an industrial heat pump (COP typically 2.5-3.5), to nibble at the thermal side, but treat that as a bonus, not the headline.

Will I end up exporting most of my generation?

Not if the system is sized sensibly. Because refrigeration gives you a 24/7 daytime baseload, most breweries self-consume 75-90% of what they generate. Oversizing the array is what forces cheap export, so size to your fridge and flexible loads, not to your total roof area.

Do I actually need a battery?

Often not, at least to start. Refrigeration already delivers high self-consumption in daylight. A battery earns its place mainly if you want to cover overnight fermentation cooling with stored daytime solar, or if your DNO limits daytime export. Model it both ways before committing.

What SEG rate will I get for exports?

Expect somewhere in the 12-16p/kWh range, it is supplier-set and moving downward (Octopus cut to 12p in March 2026). That is precisely why the plan is to consume, not export: a self-used unit is worth the ~25p you avoid paying, not the 12-16p you would earn selling it.

Where to go next

The economics of a brewery array come down to one behaviour, your glycol chiller running through the middle of the day, and one decision, sizing to that load. Run your own figures on the savings calculator, then send us your half-hourly data and we will size to your actual fermentation profile via the quote form.