Description
Hybrid heat pumps combine an air source heat pump with a traditional gas boiler. The heat pump should provide the majority of the home's heating demand, switching to the gas boiler when outdoor temperatures are very low or electricity prices are high. The system consists of an outdoor fan unit, an indoor heat exchanger and a gas boiler. If coupled with a combination boiler there is no need to install a water cylinder for domestic hot water provision.
Current status
There is little data available on the number of homes with hybrid heat pumps in the UK, but some have suggested that they could be a transitional technology for some consumers. This also means that consumers have to make a second transition, effectively paying twice to decarbonise. There is also a risk that the gas boiler is used more than intended, resulting in lower emission reductions than expected. Hybrid heat pumps are not low-carbon systems and as such, they are not eligible for the Boiler Upgrade Scheme.
| Property size | Upfront cost | Running cost |
|---|---|---|
| Small | £8,000 | £475 |
| Medium | £12,100 | £985 |
| Large | £16,000 | £1,580 |
Upfront costs will be lower than for a heat pump due to less need for supplementary work such as upgrading radiators, new pipework and a water cylinder. Consumers can further benefit from time-of-use tariffs and coupling with solar panels and/or battery storage (although with a worse return on investment compared to standalone heat pumps). Disruption from installation typically lasts around 2 to 5 days.
| Advantages | Disadvantages |
|---|---|
| Could be a transitional technology | Not a fully low-carbon technology. |
| Flexible technology for easing grid constraint | Could prolong gas grid and result in higher future utility bills |
| No hot water cylinder required | Consumers pay twice to decarbonise |
| Requires some outdoor space |
