In recent years, the heating industry has experienced a shift toward more innovative and energy-efficient solutions, driven by advances in technology and growing demand for a reduction in carbon emissions. Among these developments, the hybrid heating system has emerged, combining the strengths of traditional systems with enhanced efficiency. While traditional technologies like heat pumps and furnaces each have their merits, this new contender provides an attractive balance, as domestic and commercial developments seek smarter, more sustainable heating options. The hybrid heat pump has risen to prominence, offering flexibility and environmental benefits that cater to the demands of modern living.

What are hybrid heat pumps?

Hybrid heat pumps are heating systems that typically combine a traditional (usually gas) boiler and a heat pump which are hydraulically coupled, along with a smart control system for domestic hot water and heating. This technology leverages the strengths of both systems to provide efficient, cost-effective and flexible heating for residential or commercial buildings, and is particularly useful in multi-unit residential buildings, where space is often limited, and an immediate hot water supply is needed.

The heat pump extracts heat from the outside air using a refrigerant that evaporates at low temperatures. This thermal energy is then upgraded to a usable temperature by an electric compressor, and the heat is transferred to the home's central heating system via a heat exchanger.

An example of a hybrid heat pump system. Source: ResearchGate

During most of the year, the heat pump handles most of the heating needs, offering high energy efficiency. However, during periods of peak demand — such as cold winter days when outdoor temperatures drop and the heat pump's efficiency decreases — the gas boiler supplements the system to ensure consistent heating. Typically, the gas boiler also provides domestic hot water, although in some setups, the heat pump can assist with this, with the boiler stepping in for peak demands.

Unlike all-electric heat pumps, hybrid systems are versatile and do not require a minimum insulation level, making them suitable for a variety of homes. Better insulation improves the heat pump's contribution to overall heating needs, further enhancing efficiency.

Why are hybrid heat pumps gaining popularity?

Hybrid heat pumps have gained popularity over recent years for the following key reasons:

• Space efficiency: Hybrid heat pumps are more compact than traditional heat pumps, making them a practical replacement solution in places like residential units where space can be limited.
• Flexibility and cost-efficiency: Hybrids allow you to choose between gas and electricity based on cost fluctuations and energy source availability.
• Easy installation: Hybrid heat pumps offer easy installation thanks to their integration with traditional gas boilers, which many installers are familiar with. This makes them a more straightforward option compared to standalone heat pumps, which require specialized expertise and significant modifications to existing systems.
• Sustainability: The heat pump (which runs on electricity), primarily manages heating and does not rely on fossil fuels, meaning hybrid heat pumps emit less carbon dioxide (CO₂) than gas boilers. Furthermore, as sustainability regulations increase, hybrid heat pumps will likely be incentivized.

Air source heat pump. Source: rawpixel

Advantages of hybrid heat pumps

By combining the immediate hot water supply provided by gas boilers with the energy efficiency of heat pumps, hybrids deliver significant reductions in CO₂ emissions and can adapt to fluctuating energy costs.

As regulations around fossil fuels become more stringent, and the demand for sustainable solutions grows, hybrids stand out as a future-ready investment. The hybrid heat pump’s control allows users to select the most appropriate operation mode (i.e., heat demand covered by the heat pump, the boiler or both in parallel) for a certain building and climate to prioritize minimizing running costs or carbon emissions. Depending on building properties, local climate and chosen control settings, the heat pump’s share in space heating can largely vary.

The energy advantage

Hybrid heat pumps put less pressure on the electricity grid than stand-alone electric heat pumps, because of a smarter usage of electricity, whereby they can switch to gas when the demand for electricity is higher than the production of renewable electricity. This reduces the need for costly upgrades to the distribution network, therefore lowering the overall costs of moving toward decarbonization.

In addition, hybrid heat pumps increase the security of supply. During cold winter peaks when the demand for heat is at its highest, and the supply of electricity from renewable sources is at its lowest, hybrid systems can switch to gas, assisting in system stability and reducing the risk of power outages. Hybrid heating systems are therefore beneficial for the entire energy network, as they enable energy system integration and a smoother transition away from fossil fuels towards a decarbonized energy system.

Leveraging digital innovation

Hybrid heat pumps also offer a range of advantages thanks to the integration of innovative digital technologies, enhancing both performance and efficiency in heating systems. These systems benefit from advanced features that enable smarter operation and improved service delivery. Key highlights include:

1. Digital monitoring and diagnostics: Real-time data collection and algorithm-driven diagnostics allow for proactive maintenance, identifying issues such as air bubbles or low flow rates before they impact performance.
2. Enhanced energy efficiency: Features like adaptive algorithms optimize heating systems by monitoring factors such as resistance, outdoor temperature and flow changes, resulting in lower energy consumption and better system performance.
3. Simplified system balancing: Remote tools and apps make it easier to balance heating systems, improving comfort and energy efficiency while simplifying the commissioning process.
4. Predictive maintenance: Hydraulic resistance monitoring helps detect potential system fouling or blockages early, reducing downtime and extending system life.
5. Streamlined operations: Unified digital ecosystems and connected features support seamless integration across appliances and cloud systems, enabling efficient monitoring and management of multiple units or even larger areas.