Last updated on January 29th, 2024 at 08:35 am
In recent years, the heating industry has seen a significant shift towards renewable energy sources, prompted by environmental concerns and the need to reduce carbon emissions. This transition has led to an increasing interest in nontraditional heating systems like heat pumps, solar panels, and biomass boilers.
Homeowners are keen to explore more cost-effective and eco-friendly heating solutions that align with their preferences, property characteristics, and budget allowances. The latest developments in the energy sector, such as the October 2022 increase in the energy price cap, have made renewable energy solutions like heat pumps even more attractive.
This has led many homeowners to contemplate replacing their home’s heating system. Many homes are using old and inefficient boilers that cost them huge amounts in energy bills. For this reason, they may wonder whether to consider using heat pumps instead. This guide aims to compare both options.
In our comparison, heat pumps emerged as the winners in terms of low CO2 emissions and superior efficiency. They outperformed electric and oil combi boilers when it comes to reducing costs and emissions. However, gas boilers still excel in terms of heat yield, particularly during the frigid winter months.
| Boilers | Heat Pumps | |
| Efficiency | Highly efficient with condensing models; varies with fuel source | Remarkably efficient, with a high Coefficient of Performance (COP) |
| Environmental Impact | Emissions from fuel combustion; can use alternative, greener fuels | Zero direct emissions, environmentally friendly, depends on electricity source |
| Cost | Lower initial installation cost; operational costs may vary | Higher upfront installation cost; stable operational costs, energy-efficient |
| Maintenance | Regular maintenance required; safety and efficiency checks | Lower maintenance needs; fewer safety concerns |
| Lifespan | Can exceed 15 years with proper maintenance | 15-20+ years with proper maintenance |
| Heating Performance | Excellent in cold climates, reliable and fast | Ideal for moderate to mild climates; less effective in extreme cold |
| Space Requirements | Requires dedicated space; may need fuel storage | Requires less space for installation, indoors or outdoors |
| Sound Levels | Generally quiet operation with some noise from pumps | Minimal noise, particularly in modern models |
| Aesthetics | Often hidden in utility areas, not visible in living spaces | Indoor units visible in living spaces, design varies |
Why Compare Boilers vs. Heat Pumps?
Rising electricity and gas prices, coupled with inflation and an energy crisis, have prompted many homeowners to seek energy self-sufficiency and independence from the conventional gas and electricity grids.
In anticipation of the 2025 ban on gas boilers for newly built homes, many are turning to heat pumps as a sustainable alternative. On the other hand, boiler manufacturers are adapting by focusing on hydrogen-ready boilers to sustain their businesses. Some boiler manufacturers have also started offering heat pumps to cater to the shifting demand in heating methods.
How Do Boilers Work?
Boilers have been a tried and tested method for heating homes for many years. They operate as sealed chamber devices where a coolant, often a water-based solution or water steam, is heated to a set temperature. This heated coolant is then used to generate heat and provide hot water.
When evaluating boilers, there are specific technical parameters to consider, such as power output, efficiency rate (Coefficient of Performance or COP), type of coolant used, operating temperature, operating pressure, and hydraulic resistance.
Boilers come in various types, including biomass boilers, wood pellet boilers, condensing boilers, combi boilers, electric boilers, and gas (conventional) boilers. Each type has its unique features, making it essential for homeowners to understand their specific needs and choose the most suitable boiler type.
How Do Heat Pumps Work?
Heat pumps, though more complex in design compared to boilers, share the primary goal of heat generation. The operation of a heat pump involves absorbing and transferring thermal energy from a low-grade source, such as air or underground layers, to a heating element (the pump’s coolant) with a higher temperature.
Most heat pumps use a liquid refrigerant as the coolant, which is circulated through underground pipes (for ground source heat pumps) or external fan cover tubes (for air source heat pumps with ASHP heating).
The refrigerant absorbs heat from the air or the ground, which is then compressed to increase its temperature. The heated refrigerant is then transferred to the heating and hot water circuits of the house.
When considering a heat pump, factors to take into account include the initial installation costs, the type of refrigerant used, the pump’s size (measured in British Thermal Units or BTUs), technical features like SEER Rating (seasonal energy efficiency ratio) and HSPF Rating (heating seasonal performance factor), the pump’s warranty conditions, and any available government grants for heat pumps.
Heat pumps come in several types, including air source heat pumps, ground source heat pumps, water source heat pumps, and air to water heat pumps. Each type is designed to cater to specific heating requirements and environmental conditions.
How Efficient Are Boilers?
Boilers come in various types, including traditional, non-condensing boilers, and modern, condensing boilers. The latter are highly efficient because they recover and reuse heat that would otherwise be wasted, often achieving efficiencies above 90%.
Efficiency varies based on the type of fuel used; for instance, natural gas boilers tend to be more efficient than oil-fired ones. Electric boilers can also be highly efficient, but the cost of electricity may offset the savings.
The distribution system, such as radiators or underfloor heating, can affect overall efficiency, as some systems are more effective at delivering heat than others.
How Efficient Are Heat Pumps?
Heat pumps are renowned for their remarkable energy efficiency. They have a Coefficient of Performance (COP), which represents the ratio of heat output to electrical input. A COP greater than 1 indicates that the heat pump produces more heat energy than it consumes in electrical energy.
Air-source heat pumps can have COP values between 2 and 4, meaning they can produce 2 to 4 times the energy they consume. Ground-source heat pumps often have higher COP values.
The efficiency of heat pumps remains relatively stable across different fuel sources because they move heat rather than generate it.
Are Boilers or Heat Pumps More Eco-Friendly?
Boilers that burn natural gas or oil contribute to greenhouse gas emissions. Natural gas is the cleaner option compared to oil. The environmental impact can be reduced by using alternative fuels, such as biodiesel or biogas. These fuels are made from renewable sources and have a lower carbon footprint.
Heat pumps are considered environmentally friendly because they use electricity for heat transfer rather than combustion. This means they produce zero direct emissions, making them a greener option.
The overall environmental impact depends on the source of electricity. If your electricity comes from renewable sources like wind, solar, or hydropower, the heat pump’s carbon footprint is significantly reduced.
Are Boilers Cheaper Than Heat Pumps?
The initial cost of purchasing and installing a boiler is often lower than that of heat pumps. However, the costs can vary depending on the type of boiler and the complexity of the installation. Ongoing operational costs, especially for oil and gas boilers, can be influenced by fuel price fluctuations.
Heat pumps usually have higher upfront installation costs due to the technology involved. Ground-source heat pumps, in particular, are more expensive to install. Operational costs tend to be more stable, as they rely on electricity, which typically has consistent pricing. Over time, heat pumps can provide significant savings due to their efficiency.
Are Boilers Easier to Maintain Than Heat Pumps?
No. Boilers require regular maintenance to ensure safety and efficiency. This includes cleaning, inspections, and occasional repairs. Neglecting maintenance can lead to issues such as leaks, corrosion, and inefficient operation.
Heat pumps generally require less maintenance compared to boilers. Regular check-ups and cleaning the air filters are typically sufficient to keep them running smoothly. The absence of combustion means fewer safety concerns.
Do Heat Pumps Have a Longer Lifespan and Last Longer than Boilers?
Not necessarily. Boilers can have a relatively long lifespan, often exceeding 15 years with proper maintenance. The lifespan may vary depending on the type of boiler and its usage.
Heat pumps also have a respectable lifespan, with some systems lasting 15-20 years or more. Their durability and longevity make them a wise investment for homeowners.
Do Boilers or Heat Pumps Heat Your Home Better?
Boilers excel in providing consistent and reliable heat, especially in extremely cold climates. They can quickly heat a space and maintain a comfortable temperature.
Heat pumps perform exceptionally well in moderate and mild climates. Their efficiency makes them cost-effective in such conditions. However, their performance may decrease in extremely cold weather, which can limit their heating capacity.
Do Boilers or Heat Pumps Take Up More Space?
Boilers typically require a dedicated space, such as a basement or utility room. They may also need room for fuel storage if you have an oil boiler.
Heat pumps generally require less space for installation, making them more versatile in terms of location. They can be installed both indoors and outdoors, depending on the type.
Are Boilers or Heat Pumps More Noisy?
Usually boilers are quieter. Boilers are generally quiet during operation, with noise levels typically limited to the circulation pump and occasional burner noise. Boiler banging noises usually indicate a problem.
Heat pumps can produce some noise, especially air-source heat pumps with outdoor units. However, modern units are designed to minimize noise, and there are options for quieter operation, such as variable-speed compressors.
Are Boilers or Heat Pumps More Aesthetic?
Boilers usually look more discrete. They are often tucked away in utility rooms, basements, or dedicated boiler rooms, keeping them out of sight. This can be an advantage if you prefer not to have heating equipment visible in your living spaces.
Heat pumps, especially ductless or mini-split systems, have indoor units that are visible in living spaces. While they are designed to be unobtrusive, their appearance may influence your choice based on your home’s aesthetics.
Which is Better? Boilers or Heat Pumps?
Given the high initial costs and limited heating output of heat pumps, gas boilers remain a cost-effective choice for certain homeowners, especially during peak heating demand periods. The ongoing improvements in heat pump technology may, in the future, raise their performance to such a level that they become the undisputed champions of efficiency.
The UK government’s support for the transition to low carbon heating solutions also indicates a potential shift towards these systems.
However, before hastily choosing a heat pump over a boiler, you should still note that the traditional gas boiler still has its merits. Precarious measures and considerations must be taken when dealing with gas-operated devices.
As the energy landscape evolves, homeowners should carefully assess their needs, budget constraints, and the specific conditions of their properties to make the right choice between boilers and heat pumps for their heating solutions.
