Phoenix Journal · Energy & Efficiency
The technology works - but standard units cannot make safe kitchen hot water, and the spark gap leaves running costs near parity. Where a heat pump earns its place, and where it does not.
Heat pumps
Heat pumps arrive in a commercial kitchen wrapped in a big savings figure and a net-zero headline. The technology is genuinely good - but the pitch and the plant room are two different places, and the gap between them is where operators get caught. Here is the honest comparison.
The question is rarely whether heat pumps work - they do. It is whether one is the right answer for a kitchen's hot water and heating, at what cost, and against what it replaces. Set the hype beside the reality and the picture gets a lot more useful.
The pitch
The sales case is clean and mostly true in outline. A heat pump moves heat rather than burning fuel, so it delivers three to four units of heat for every unit of electricity - an effective efficiency of 300 to 400 percent against a gas boiler's 90 to 95. It cuts on-site carbon, supports the sustainability credentials guests and procurement teams increasingly ask for, and in a hot-water-heavy operation like a hotel or a busy kitchen there is plenty of demand for it to serve.
All of that is real. What the headline leaves out is three things that decide whether the saving actually lands: temperature, price and plant.
The reality
Temperature. A standard air-source heat pump is designed to deliver water at 45 to 55 degrees - fine for underfloor heating, not enough for safe commercial hot water, which needs to reach around 60 degrees and above to control Legionella. Kitchen and dishwasher hot water needs a high-temperature unit, typically running a propane refrigerant to reach 70 to 85 degrees, which costs more and is a different specification from the domestic box people picture.
The spark gap. Electricity in 2026 costs roughly three to four times as much per unit as gas. A heat pump running at a coefficient of performance of three to four therefore lands roughly level with a good gas boiler on running cost - not the dramatic saving the headline implies. The carbon case is strong; the pure pounds-and-pence case is often close to a wash, and swings on your exact tariffs.
Plant. High-temperature units need space, a sensible outdoor location, and larger, well-designed hot-water cylinders to work efficiently. In a tight back-of-house that is not a given.
The honest verdict
None of that means don't - it means specify it for what it is good at. It works best running alongside an existing boiler rather than replacing it outright, covering the steady base hot-water load and leaving the boiler for peaks - a bivalent setup that hedges both cost and risk. It suits sites where hot water is the dominant, steady load, and it is at its best where there is waste heat to harvest: reclaiming heat rejected by walk-in freezers and chilled rooms to pre-warm hot water is close to free energy, and sits naturally alongside heat recovery in kitchen ventilation.
Where it disappoints is as a like-for-like boiler swap chasing a bill cut, on a cramped site with no room for the plant, or where the case was built on a domestic grant. The Boiler Upgrade Scheme is primarily for homes and small non-domestic buildings, and a typical commercial kitchen usually relies on capital allowances instead - so check current eligibility before you count on any grant. Read together with reducing a hospitality carbon footprint, the sensible move is usually to treat a heat pump as a strong carbon play and a break-even cost play, and size it accordingly.
One more reality check before signing off a scheme: model it on your own tariffs and demand, not a brochure average. The running-cost verdict swings entirely on the gap between your electricity and gas unit rates and the coefficient of performance the unit actually achieves in service - which is usually below the headline figure on the coldest days, exactly when demand peaks. Get those two numbers from your own bills and a reputable performance estimate, and the decision stops being a matter of faith and starts being arithmetic.
Questions
Only a high-temperature unit can. Standard heat pumps top out around 45 to 55 degrees, below the temperature needed to control Legionella in commercial hot water. High-temperature models using a propane refrigerant reach 70 to 85 degrees and can serve kitchen and dishwasher demand, but they cost more and need careful cylinder design.
It will cut carbon reliably; whether it cuts cost depends on your tariffs. Because electricity costs roughly three to four times as much per unit as gas, a heat pump running at a coefficient of performance of three to four lands close to level with a good gas boiler on running cost. Treat the carbon case as the strong one and model the money on your actual rates.
Often the better move is to run one alongside the boiler rather than instead of it - a bivalent system covering the steady base load, with the boiler handling peaks. That hedges cost and risk, suits how kitchen hot-water demand behaves, and avoids betting a tight plant room on a single high-temperature unit.
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