As the world moves towards a more sustainable future, hybrid heat pumps are emerging as a key player in the transition to decarbonize heating systems, particularly in older and larger homes. This article delves into the various aspects of hybrid heat pumps, their benefits, and the potential for homeowners to adopt this technology.
What is a Hybrid Heat Pump?
A hybrid heat pump is an innovative heating solution that combines an air source heat pump with a gas or oil boiler. This combination allows the heat pump to operate at its optimal efficiency while the boiler supplements the heating demands when required. Hybrid systems are designed to control which heat source is activated based on efficiency or energy cost targets.
How Do Hybrid Heat Pumps Work?
Most air source heat pumps operate at lower temperatures (40-45 degrees Celsius) compared to traditional fossil fuel systems (65-75 degrees Celsius). Without proper insulation or larger radiators, low-temperature heat pumps may be unsuitable for existing homes.
Hybrid heat pumps allow the heat pump to run at an efficient temperature of 40 degrees Celsius, providing sufficient heat for most of the year. As external temperatures drop or hot water demand increases, the gas or oil boiler steps in to raise the water temperature. This approach has been tested in various trials, with heat pumps contributing between 50% and 80% of heating and hot water supplies in a range of homes.
Hybrid vs Bivalent Systems
Hybrid System
A hybrid system features a purpose-built combined heat pump and oil or gas boiler from the same manufacturer. In this setup, the heat pump operates most of the time, while the boiler supplements it as needed.
Bivalent System
A bivalent system pairs any heat pump with any gas or oil boiler, combined via a buffer tank. This allows you to potentially use your existing boiler if it is still in good condition. In this setup, the heat pump operates as much as possible, while the boiler kicks in when the heat pump cannot meet the demand.
The Need for Hybrid Heat Pumps
The UK is legally obligated to reach net-zero emissions by 2050, with homes accounting for 20% of greenhouse gas emissions. Insulating homes and reducing heat requirements can prepare them for low-temperature air source heat pumps. However, poorly insulated and larger homes may still require fossil fuels in the medium term to provide higher temperatures for conventional radiator systems.
In 2019, the Committee for Climate Change (CCC) recognized the importance of hybrid heat pumps in decarbonizing UK homes and set a target of installing 10 million units by 2035.
Benefits of Hybrid Heat Pumps for UK Households
Hybrid heat pumps offer UK households the opportunity to reduce their gas or oil consumption without needing immediate insulation upgrades or radiator replacements. Off-grid homes can also benefit from reduced running costs. If the heat pump is set to run efficiently, those on the mains gas grid can expect similar running costs to conventional gas heating, depending on electricity costs.
Leading Hybrid Heat Pump Manufacturers
Several options are available for homeowners who wish to combine a heat pump with a fossil fuel boiler. Some manufacturers offer integrated hybrid solutions, while others allow for pairing any heat pump and boiler via a buffer tank.
- Daikin: Altherma heat pump (5kW or 8kW)
- Vaillant: aroTHERM heat pump with VRC control (5, 8, 11, and 15kW)
- Grant: Aerona R32 heat pump (17kW)
- Firebird: Enviroair heat pump (7.5-16kW) and Envirogreen oil boiler
Financial Support for Hybrid Heat Pumps
Hybrid heat pumps are eligible for the Renewable Heat Incentive (RHI) payback scheme. However, installations must be metered to ensure that homeowners are paid for the renewable energy they generate. For more information on the domestic RHI, consult our comprehensive guide.
Making the Right Choice for Your Home
If you’re considering a renewable heating technology for your home, it’s essential to get impartial, expert advice to help you make the best decision. Our team can assist you in selecting the right heating system and exploring a full range of heat sources. To learn more about our groundbreaking services for consumers, please contact us.
Further Reading
High Temperature Heat Pumps
Discover more about high temperature heat pumps and their suitability for home heating in our in-depth guide. We explore the technology, its applications, and the manufacturers producing these systems.
Domestic Renewable Heat Incentive
Our ultimate guide to grant funding available for renewable heating systems covers everything you need to know about the RHI. Note that the scheme ends on 31 March 2022, so your system must be installed and commissioned by this date.
References
- Hybrid Heat Pumps – Final report for Department for Business, Energy & Industrial Strategy – View Report
In conclusion, hybrid heat pumps present a promising solution for decarbonizing home heating systems, especially in older and larger homes. By combining the efficiency of air source heat pumps with the supplementary power of gas or oil boilers, these systems can significantly reduce greenhouse gas emissions and help the UK reach its net-zero target by 2050. With numerous manufacturers and financial support options available, there has never been a better time for homeowners to consider hybrid heat pumps as a sustainable heating solution.
