Boiler vs Heat pumps
Boilers vs Heat pumps
There are a number of key differences between a boiler and a heat pump. Here we list some of key differences.
COMMON QUESTIONS
One of the main concerns about heat pump disadvantages is that they are noisy. This just isn’t the case with modern units. There are now strict regulations on how loud this can be (around 40 – 60 decibels within one metre). Our heat pump is only 42bd from 1m.
That’s roughly the same as a fridge freezer or a gas boiler and because they’re outside, the noise will rarely be heard. Our site survey includes a noise check to ensure this.
Read more in our Knowledge Hub page on this topic.
Before installation we do a thorough home survey to ensure the heat pump system we install is optimised for your space.
Unlike a gas boiler, where high bursts of energy are produced, rapidly heating, a heat pump is designed to stay on for longer without costing you more – keeping consistent temperature throughout the day. The rapid inefficient burst of burnt energy with a boiler verses the slow consistent operation of a heat pump is one of the core reasons for the massive difference in heat pump efficiency and cost savings.
Air source heat pumps can actually work in temperatures as low as -20 °C when properly installed. Norway, Sweden, and Finland have the highest heat pump adoption rates in Europe, and are equally some of the coldest countries.
When it gets very cold, the heat pump will need to use a bit more energy than usual to keep your home cosy, but as our heat pump is designed for Swedish winters, the UK’s milder climate means our heat pump has no problem keeping up.
Our heat pumps are also installed with outdoor temperature sensors and climate control systems, which can engage immersion heaters to boost hot water if in the rare case the heat pump isn’t efficiently getting your hot water up to the design flow temperature.
With the Government’s Boiler Upgrade Scheme £7,500 grant, you can get an ROI on your investment and saving on your gas bill quickly. We give you a detailed overview of your savings, and comparison to new and older gas boilers when you complete our online questionnaire.
A heat pump can last 20 years – about twice as long as a boiler – and they need less pricey maintenance.
Our installations include a 2, 5 or 7 year warranty depending on your service packages.
Read about our industry leading maintenance packages here.
These days heat pumps can actually heat water up to these higher temperatures.
The question is, why would you want to? Heat pumps work more efficiently at lower temperatures and with modern low temperature radiators you just don’t need to heat your water up to 60 degrees, or higher.
By running your radiators slightly longer at a lower temperature you save money, have less heat loss in your radiators, and have a more pleasant living environment.
Heat pumps are smart. They use outside temperatures to control your heating curves and with your input they can learn your usage and active times in the house to ensure that slow and steady heat is produced so when you walk in your home the temperature is perfect.
Then it works slow and steady in low eco modes to maintain that temperature.
You don’t need to worry about going to the thermostat and hitting boost.
ABoilers vs heat pumps
The government only offers financial support to low carbon solutions.
See our separate articles on government policy and support for heat pumps:
- EPC regulation changes: understand the changing landscape for rental properties and landlords. Stay ahead of the demand and changes due in 2025. Click here for more | https://bills.parliament.uk/bills/3036
- Boiler Upgrade Scheme: how long will the subsidy last and how do I get the subsidy before it stops. Click here for more.
- 2025 Gas Boiler ban: the government plans to phase out gas boilers and replace them with low carbon alternatives. Click here for more.
Environmental Impact Heat Pumps
The heating of our homes accounts for 14% of the UK’s total carbon emissions. New energy methods, such as heat pumps, can make a significant difference to lowering this.
The CO₂ to produce 1kwh of heating energy:
- New Gas Boiler: 0.21 CO₂/kwh
- Old Gas Boiler: 0.23 CO₂/kwh
- Oil Boiler: 0.31 CO₂/kwh
- AURORA II: 0.11 CO₂/kwh
As an example:
- A 120m² house, with EPC of D could save 3,104 kg CO₂ a year with an AURORA II heat pump compared to their existing gas boiler.
- 4,600 kg CO₂ a year is the average UK per capita emissions per year (World Bank UK Data)
- This house example had 2 people living in it
- Their new household CO₂ a year is estimated at 3,048 kg.
- This equals 34% less CO₂ per person per year
The payback period and return on your heat pump investment depends on which heat pump you have, the gas consumption you would have if you didn’t have a heat pump and the energy costs. Once you have all this mapped out, you can do a calculation on this. Adlår’s quick savings questionnaire can give you a good idea of your homes specific situation.
The Regulatory Assistance Project (RAP) suggests that if designed and installed well a heat pump can be cheaper than a gas boiler by up to 27%.
Using a rough demostration from People Powered Retrofit’s home assessment tool, it’s possible to see the potential of a low, medium and high impact retrofit, and the size of heat pump that could then be used i.e. small, medium and large.
- Baseline scenario: Peak heat load = 11.1kW (large heat pump required)
- Scenario 1 low impact retrofit: Peak heat load = 8.8kW (medium heat pump)
- Scenario 2 medium impact retrofit: Peak heat load = 5.1kW (small heat pump)
- Scenario 3 high impact retrofit: Peak heat load = 3.8kW (small heat pump)
What can be seen here is that any kind of retrofit reduces the size of the heat pump required – but a deep retrofit has a significant impact.
How much value does a heat pump add to your home?
A heat pump is considered an efficient, sustainable way of heating and cooling your home.
Added value to your property includes:
- Renewable installation
- Heat Pump Costs – Savings, Payback, InvestmentLower energy bills
- Higher EPC score
- Heating and cooling features
The outside main unit is roughly 1m x 1m x 1.5m, it needs a space of ~1m meter infront and to each side to allow optimal airflow into the unit.
Inside you need space for a hot water cylinder, which is roughly 2m x 1m x1m (the size of a small-medium sized modern fridge), which you can place on the ground or first floor of your home (the closer to the outside the better).
Heat pumps can work in nearly all homes, our 14kW unit is powerful enough for a 200m² home. We can install multiple units, but we need to do a proper onsite survey to establish if this is feasible and affordable.
We pride ourselves on our initial questionnaire being more detailed then other providers, so you can immediately receive a solid understanding of your heat loss, costs and savings.
OPERATION COMPARISON
We use the analogy of the tortoise and the hare to visualise boilers vs heat pumps when it comes to heating.
A gas boiler works fast, with high energy output to heat up water, whereas a heat pump works slow and steady holding the temperature at a more consistent level.
We also like to claim, as the tortoise, the heat pump wins the race.
Traditional boilers tend to be oversized compared to heat pumps in terms of capacity.
As a general rule a house that requires 5kW of energy would tend to have a 30kW boiler installed.
This is because combi boilers are designed to be reactive, providing heating on demand. In this case, your thermostat will monitor your room temperature and turn the system ON and OFF to meet the desired room temperature. This creates a yo-yo affect between desired temperature and actual, and also between your inflow water temperature and your design flow temperature of your system (~35°C for underfloor heating and 45~80°C for radiators).
This greater temperature rise in this scenario requires more power.
Heat pumps heat your water much more gently, over a longer period of time, and keep a constant flow.
Having heat pumps with a 30kW capacity requires an expensive unit, and usually 3-phase power to achieve. As a result, heat pumps are designed more carefully to facilitate lower capacity.
Heat pumps keep water flowing and by maintaining constant temperature in the system, there is rarely a need for a large surge in power to combat dropping room temperatures. The heat pump works to keep the water inflow temperature within a couple of degrees of your design flow temperature, rather than 5~10 degrees, as can be the case in a boiler system.
Adlår heat pumps are installed with extra capacity built in, and in combination with temperature sensors and pre-programmed environmental heating curves, we can account for the worst case scenarios (when outside temperature drops below -10°C, and the hot water temperature isn’t keeping up with your thermostat demanded temperature).
Our extra capacity includes:
- 3kW Immersion heater, within a 60 or 90 litre buffer tank
- 1.5kW domestic hot water (DHW) cylinder air source heat pump (ASHP)
The buffer tank smooths out demand, having heating hot water available to distribute to your heating system. The 3kW immersion heater can be activated if the heat pump’s capacity is close to maximum and the temperature settings aren’t being met by the heat pump alone.
The 1.5kW DHW ASHP cylinder works independently from the heating, to supply only for your domestic hot water. As DHW takes priority over room heating in most systems, by splitting the system as we do, we avoid the heat pump being in over capacity and prevents heating capacity for hot water from ever being diverted to the DHW.
governement support
Heat pumps have government support in the form of the Boiler Upgrade Scheme BUS. Boiler Upgrade Scheme – £7,500 Grant
The current government grant has enough funding for roughly 90,000 homes ONLY. It also has a three year time limit which ends March 31st, 2025.
Apply for the Boiler Upgrade Scheme: Check if you’re eligible – GOV.UK (www.gov.uk)
Apply for the Boiler Upgrade Scheme: Check if you’re eligible – GOV.UK (www.gov.uk)
You’re eligible for a grant if all the following are true. You must:
- own the property you’re applying for (including if it’s a business, a second home, or a property you rent out to tenants)
- have installed (or plan to install) your new heating system on or after 1 April 2022
- be replacing fossil fuel heating systems (such as oil, gas or electric)
You’re still eligible if you’ve already had funding to make your property more energy efficient, for example by insulating it.
Apply for the Boiler Upgrade Scheme: Check if you’re eligible – GOV.UK (www.gov.uk)
Your property must have a valid Energy Performance Certificate (EPC) with no outstanding recommendations for loft or cavity wall insulation.
Find out what to do if your property has recommendations for loft or cavity wall insulation.
If you’re not sure whether your property is suitable for a low carbon heating system, speak to an MCS certified installer (Adlår). They can tell you about your options.
Apply for the Boiler Upgrade Scheme: Check if you’re eligible – GOV.UK (www.gov.uk)
You cannot get a grant for:
- most new build properties
- social housing
- a property that’s already been given government funding or support for a heat pump or biomass boiler
- To replace a low carbon heating system.
Apply for the Boiler Upgrade Scheme: Get help – GOV.UK (www.gov.uk)
You can also contact Ofgem if you need help with the Boiler Upgrade Scheme.
Ofgem
BUS.enquiry@ofgem.gov.uk
Telephone: 0330 053 2006
Monday, Tuesday and Thursday, 9:30am to 4:30pm
Wednesday, 9:30am to 12:30pm
Friday, 9:30am to 4pm
You can get one grant per property:
- £5,000 towards an air source heat pump
HEAT PUMPS INCREASE PROPERTY VALUE:
How much does a heat pump add value to my home?
A WWF report, in conjunction with Scottish Power (Better Homes, Cooler Planet) has shown a heat pump could add between 1.7% and 3.0% to the value of your home, or £5,015 (1.7%) to £8,850 (3.0%) based on the Office of National Statistics UK average house price of £295,000 in November 2022.
The Better Homes, Cooler Planet report also estimated that by installing a heat pump in your home you could reduce your heating costs by around 37%. or £1,290.90 on average.
The report also highlighted a heat pump outperforming other forms of renewables, such as electric vehicle charging or solar panels.
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According to Knight Frank’s Property Market Insights, improving your EPC rating can improve your home value by a further 20%.
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Additionally, as Adlår’s heat pumps can facilitate cooling, your property value could increase by as much as 2.5%.
ENVIRONMENTAL IMPACT
The heating of our homes accounts for 14% of the UK’s total carbon emissions. New energy methods, such as heat pumps, can make a significant difference to lowering this.
The CO₂ to produce 1kwh of heating energy:
- New Gas Boiler: 0.21 CO₂/kwh
- Old Gas Boiler: 0.23 CO₂/kwh
- Oil Boiler: 0.31 CO₂/kwh
- AURORA II: 0.11 CO₂/kwh
As an example:
- A 120m² house, with EPC of D could save 3,104 kg CO₂ a year with an AURORA II heat pump compared to their existing gas boiler.
- 4,600 kg CO₂ a year is the average UK per capita emissions per year (World Bank UK Data)
- This house example had 2 people living in it
- Their new household CO₂ a year is estimated at 3,048 kg.
- This equals 34% less CO₂ per person per year
Heat pump efficiency vs. boiler
The average COP value should be between 4 and 6. So this means that when you lose 1 kW of energy you get 4 to 6 kW of heat in return. This is an efficiency of 400% to 600%!
When we look at a brand new gas boiler, the efficiency is roughly 90%, for a 5-10 year old boiler the efficiency would be worse, closer to roughly 80%. The efficiency is a lot lower.
Understand more in our Knowledge Hub Article on how heat pumps work.
Energy costs
The following case study from the WWF in collaboration with Scottish Power shows heat pump usage in a typical UK home. The typical home is defined as follows:
- Region: UK Average
- Typology: Semi-detached home
- Constructed: 1900-1966
- Floor Area: 120m²
Energy Efficiency Ratings:
- Poorly insulated house: EE0
- Improved House: EE4
- Well-insulated house: EE5
Energy Efficiency:
- Old Boiler: 66%
- Heat pump SCO: 2.35-3.55 (Adlår AURORA II 4.89@35°C to 3.48@50°C
| Old Gas Boiler | Metric | |||
|---|---|---|---|---|
| Energy Efficiency Standard | Rating | EE0 | EE4 | EE5 |
| Annual Energy Costs | £/year | £2,416 | £1,991 | £1,629 |
| Reduction in costs | % | n/a | 17.6% | 32.6% |
| Annual Energy Costs* | £/year | £2,265 | £1,840 | £1,478 |
| Reduction incosts* | % | n/a | 18.8% | 34.8% |
| Air Source Heat Pump | Metric | |||
|---|---|---|---|---|
| Energy Efficiency Standard | Rating | EE0 | EE4 | EE5 |
| Annual Energy Costs | £/year | £2,412 | £1,651 | £1,512 |
| Reduction in costs | % | 0.2% | 32.6% | 37.4% |
| Annual Energy Costs* | £/year | £2,073 | £1,411 | £1,290 |
| Reduction incosts* | % | 8.5% | 37.7% | 43.1% |
*Annual Energy Costs with Legacy Policy Costs Moved (vs. poorly insulated house with old gas boiler, with legacy policy costs moved)
cooling WITH heat pumps
As Adlår’s heat pumps can facilitate cooling, your property value could increase by as much as 2.5%.
ASHPs provide both heating and cooling technology so they can be a versatile solution for year-round comfort. They can reverse their operation, extracting heat from the home and expelling it outside during the summer, therefore acting as a sort of air conditioner. The heat pump works by absorbing heat from the outside environment during the heating phase, and in the cool phase reserves the process, absorbing heat from your home and sending it back out into the outside air.
2-in-1
Heat pumps offer the same comfort as a traditional HVAC system, essentially it is a 2-in-1 unit which can heat and cool.
This is by far the most efficient solution for your home if you’re considering having a HVAC unit to keep you cool in winter.
HEAT PUMPS REMOVE HUMIDITY
Better than a traditional air conditioner, heat pumps also remove humidity from your home, making the cooling feel much nicer.
What is the payback period of a heat pump?
The payback period also depends on which heat pump you have, the gas consumption you would have if you didn’t have a heat pump and the energy costs. Once you have all this mapped out, you can do a calculation on this. Adlår’s quick savings questionnaire can give you a good idea of your homes specific situation.
GET A QUICK OVERVIEW OF YOUR COSTS AND SAVINGS
Example payback period heat pump calculation with 2022 ENERGY PRICE
2022 Key Data:
- Electric/kWh: £0.67
- Gas/kWh: £0.17
- Standing Day Rate Gas: £0.28/day
Example Data:
- Design Flow Temperature: 35°C (underfloor heating)
- Floor Space: 128m²
- Total Energy Consumption/year: 20,748 kWh
Calculations:
- Aurora II Energy Cost: £3,498.90
- Old Gas Boiler Cost: £4,522.00
- Full Electric Savings: £102.20 (£0.28*365)
- AURORA II Purchase Price: £3,800.00
Savings:
- Energy Saving/year: £1,125.26
- Payback Period: 3.38 years
EXAMPLE PAYBACK PERIOD HEAT PUMP CALCULATION WITH 2023 ENERGY PRICE
2023 Key Data:
- Electric/kWh: £0.30
- Gas/kWh: £0.08
- Standing Day Rate Gas: £0.29/day
Example Data:
- Design Flow Temperature: 35°C (underfloor heating)
- Floor Space: 128m²
- Total Energy Consumption/year: 20,748 kWh
Calculations:
- Aurora II Energy Cost: £1,628.96
- Old Gas Boiler Cost: £2,128.00
- Full Electric Savings: £109.50 (£0.29*365)
- AURORA II Purchase Price: £3,800.00
Savings:
- Energy Saving/year: £608.54
- Payback Period: 6.24 years
What this shows is that heat pumps save you a lot more as energy prices fluctuate up. We recommend you look at energy price trends to inform your decisions, but at Adlår we don’t see energy prices raising as a general trend and consequence of the global economic climate. This makes getting a heat pump now, even more advantageous.
Comparison:
- 2022 Savings: £1,125.26
- 2023 Savings: £608.54
- Percentage increase in gas price: +113%
- Percentage increase in electric price: +123%
- Percentage increase in savings: +85%
Want to know more about consumption? Then also read our article on the consumption and efficiency of a heat pump.
PAYBACK with property value Increase:
A HEAT PUMP CHANGES YOUR EPC
The calculations behind the EPC rating are not based purely on efficiency, they’re based on the cost of heating and powering your home. That means the cheaper the running costs, the better the rating.
It is therefore important to get a detailed survey done of your property. The best start is to complete our market leading initial assessment to understand your savings.
Landlords EPC C Upgrade
Using an example of a property we installed a heat pump on. The comparable data shows you how a heat pump can be the best solution to improve your EPC.
AURORA II 10kW HEAT PUMP
- Price: £5,853
- Yearly saving: £671*
- EPC Increase: 8**
Comparison:
- Heat Pump: £731.63 Cost/EPC
- Wall Insulation: £1,250 Cost/EPC
- Solar Panels: £785.71 Cost/EPC
As can be seen here the heat pump is the most cost effective solution in this case. It is important that this varies property to property and again we encourage you to complete our survey for accurate results for your home’s specific circumstances.
