Real-World Costs vs Manufacturer Claims
Manufacturers often quote seasonal coefficient of performance (SCOP) figures of 3.5–4.5. In our experience servicing hundreds of systems across Hampshire, real-world SCOP typically ranges from 2.5 to 3.5, depending heavily on installation quality, system design, and user behaviour.
The gap between claimed and actual performance isn't because the technology doesn't work — it's because many systems are poorly commissioned, incorrectly sized, or running with suboptimal settings — all of which are correctable through commissioning and optimisation.
Typical Annual Costs for a 3-Bed Home
Based on systems we maintain, a well-commissioned air source heat pump in a 3-bedroom semi-detached home in Hampshire typically consumes 4,000–5,500 kWh of electricity annually for heating and hot water. At current electricity rates (approximately 24.5p/kWh), that's £980–£1,350 per year.
Compare this to gas heating costs for the same property: approximately 12,000–15,000 kWh at 6.5p/kWh = £780–£975. Yes, a well-set-up heat pump can cost slightly more than gas at current tariffs — but with a heat pump tariff and proper optimisation, costs become very comparable.
The Factors That Affect Your Costs Most
Flow temperature is the single biggest controllable factor. Every degree you reduce flow temperature improves efficiency by approximately 2–3%. A system running at 45°C will cost significantly less than one running at 55°C.
Other major factors include: insulation quality, radiator sizing, weather compensation settings, hot water scheduling, and whether the system is set to run continuously or in timed bursts. We optimise all of these during our heat pump servicing and health check visits.