Heat Pump vs Gas Boiler: Tom’s Path to Lower Bills

Oct 18, 2023 | Expert Advice

In a quiet Victorian terrace nestled in County Durham, Northeast England, we meet Tom. He’s a regular guy with a simple yet impactful mission: to make his home friendly to both his wallet and the environment.

Tom turned to an air source heat pump (a technology included in the the ECO4 Scheme although it seems he might have financed his ASHP privately), to achieve his green home goals (learn more about Air Source Heat Pump Grant for homeowners).

Let’s delve into Tom’s review of air source heat pump vs gas boiler, broken down into digestible insights, just the way Tom prefers.

Making the Green Switch

On 13th July 2021, Tom replaced his old gas boiler and welcomed a modern air source heat pump. Unlike traditional boilers that burn gas to produce heat, a heat pump uses a small amount of electricity to extract heat from the outdoor air to warm up the indoors, a method supported by the Energy Saving Trust for its efficiency and low carbon footprint. It was a smart and eco-friendly choice that resonated with Tom’s love for the environment and his keen eye for savings.


How Air Source Heat Pump Works: A Simple Explanation

An air source heat pump is a device that takes in air from the outside and uses a small amount of electricity to generate heat for your home. Unlike a traditional gas boiler, which burns gas to create heat, a heat pump is more efficient and has a lower carbon footprint.

Annual Performance Check

Being meticulous, Tom decided to evaluate how his heat pump was performing a year later. He discovered that in the second year, the heat pump used 3,863 kilowatt-hours of electricity to generate a cosy 12,171 kilowatt-hours of heat. Interestingly, it used less electricity than the year before but provided more warmth! This improvement in efficiency is in line with the findings of a study by the Department of Energy & Climate Change, showcasing the long-term benefits of heat pumps.

Note: Kilowatt-hours (kWh) is a measure of energy. Think of it as the ‘miles per gallon’ for heating systems, helping you understand how much energy is used to produce heat.

electricity used by air source heat pump year two

Jargon Buster: CoP (Coefficient of Performance)

This is a measure of how efficiently a heat pump operates. A CoP of 3 means that for every unit of electricity used, three units of heat are produced.

Efficiency on the Rise

Tom was happy to find that the efficiency of his heat pump increased from a CoP (Coefficient of Performance) of 2.96 to 3.15 over the year, indicating a 6% efficiency improvement. This meant that for every unit of electricity used, three units of heat were produced. The better efficiency not only kept his home warmer but also contributed to the cost savings, proving that the system was becoming more effective over time. 

Table: Heat Pump Performance Over Two Years

Year Electricity Used (kWh) Heat Produced (kWh) CoP
1 4,000 11,841 2.96
2 3,863 12,171 3.15
air source heat pump back uk home

Air Source Heat Pump Running Cost vs Gas Boiler

Despite energy prices soaring last year, Tom’s heat pump stood firm. With some savvy energy plans, the cost to run the pump was about 9.2 pence for every kilowatt-hour of heat, compared to a boiler’s 10.84 pence. Over the year, Tom saved a neat £194 pounds! In percentage terms, that’s a saving of about 15% on his heating bills. In the battle between a gas boiler vs air source heat pump, the latter is winning.

Table: Tom’s yearly savings with air source heat pump

Heating System Cost per kWh of heat (pence) Total cost fo 12,171 kWh (GBP) Savings (GBP)
Heat Pump 9.2 1,125 194
Gas Boiler (95%) 10.84 1,319

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Looking Towards Solar Skies

Tom’s not stopping there in his air source heat pump efficiency vs gas boiler improvements. He’s considering solar panels and a battery to capture and store sunshine for lower bills and a smaller carbon footprint. His neighbours are already reaping the benefits of solar energy, and Tom might join the solar brigade soon.

The combination of solar panels and air source heat pumps, as recommended by the Centre for Alternative Technology, could cut down his bills even further, making his home a beacon of green living.

solar panels air source het pump integration

Considering Future Upgrades

Despite the success, Tom does have one small regret. If given another chance, he’d opt for bigger radiators (learn more about best electric radiators) to lower the system’s flow temperature and boost efficiency even further. This is a valuable lesson for anyone considering a heat pump installation, showcasing the importance of system design in maximizing benefits.

The Benefits of Switching to Heat Pump vs Gas Boiler

Here’s a quick look at the perks Tom enjoyed with his heat pump:

Cost Efficiency

The pump used less electricity but generated more heat, saving Tom £194 pounds over the year.


The heat pump reduced his home’s heating emissions by a significant 66%, keeping 1.55 tonnes of CO2 from entering the atmosphere, aligning with the UK’s carbon reduction targets.

Future Savings Potential

With plans for solar panels and a battery, Tom’s setting the stage for more savings and a cleaner, greener home.

Simple Living, Big Impact:

Tom’s story demonstrates how a simple switch of the heating system in your home can lead to warm homes, full pockets, and a happy planet.

Table: Tom’s yearly savings with air source heat pump

Power Source Electricity Used (kWh) Emissions (tonnes of CO2)
Heat Pump 3,863 0.8
Gas Boiler 2.35
air source heat pump vs gas cheaper

A Journey of Warmth and Savings

Tom’s journey shows it’s not just about the extra cash or the snug nights during winter; it’s about making a modest change for a huge impact.

His story is a good example of how a simple switch to an air source heat pump from a gas boiler can bring warmth, savings, and a cleaner environment. His narrative is an eye-opener on how making informed choices can lead to a comfortable, eco-friendly living while saving money.

So, the next time you’re bundled up on the sofa, perhaps ponder over how air source heat pumps could warm not just your toes, but also your heart and our precious planet.

And if Tom’s story has inspired you, perhaps it’s time to explore how an air source heat pump could be the hero of your own green home adventure, guided by resources from the Energy Company Obligation and the Energy Saving Trust.

Article written by

Abigail Hall

Abbie is an ECO4 specialist helping homeowners to enhance their home’s energy efficiency using government funding. With her guidance, many have adopted sustainable living practices and reduced their energy bills.
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