Why you should use a heat pump in your next build.

An air source heat pump (ASHP) and a gas boiler are two common ways to provide space heating and hot water in residential settings. Here's a comparison of their benefits in the context of a modern, well-insulated timber frame house:

1. Efficiency:

   • ASHP: Heat pumps are known for their high efficiency. They typically operate at a coefficient of performance (COP) of between 2 and 4. This means for every unit of electricity used to run the pump, 2 to 4 units of heat are produced, making them 200% to 400% efficient in ideal conditions.

   • Gas Boiler: The efficiency of modern condensing gas boilers is typically between 90% and 95%. This means that for every unit of gas burned, 0.90 to 0.95 units of heat are produced.

2. Environmental Impact:

   • ASHP: Produces zero direct emissions since it doesn’t burn any fuel on-site. If powered by renewable electricity, it can be a very low-carbon heating solution.

   • Gas Boiler: Emits carbon dioxide and other greenhouse gases directly when burning natural gas. Even the most efficient gas boilers contribute to greenhouse gas emissions.

3. Fuel Costs and Stability:

   • ASHP: Relies on electricity, whose price can vary based on regional factors. In areas with abundant renewable energy, the price may be more stable.

   • Gas Boiler: Relies on gas prices, which can be subject to volatility based on global market conditions.

4. Maintenance and Lifespan:

   • ASHP: Generally has fewer moving parts than combustion-based systems, leading to potentially lower maintenance costs. The lifespan is usually between 15-20 years.

   • Gas Boiler: Requires regular maintenance, such as annual servicing, to ensure safe and efficient operation. Typical lifespan is around 10-15 years.

5. Safety:

   • ASHP: Does not burn fuel, so there's no risk of gas leaks or carbon monoxide poisoning.

   • Gas Boiler: Though modern boilers are safe when installed and maintained correctly, there's always a slight risk of gas leaks or carbon monoxide issues.

6. Installation Costs:

   • ASHP: Can have higher upfront costs than a gas boiler, but there may be rebates or incentives available to offset these costs.

   • Gas Boiler: Often has a lower initial cost compared to ASHP, especially if replacing an older gas boiler in a house that already has gas infrastructure.

7. Space and Aesthetics:

   • ASHP: Requires an outdoor unit similar to an air conditioning unit.

   • Gas Boiler: Typically installed indoors, either in a dedicated boiler room, basement, or utility space.

For a modern well-insulated timber frame house, an ASHP could be particularly advantageous given its efficiency, environmental benefits, and safety profile. Such homes, with good insulation, will require less energy to heat, making the high efficiency of the ASHP even more beneficial. However, the best choice will also depend on local energy prices, available incentives, and personal preferences.