The costs and savings of green home energy products

As we all play our part in reducing our carbon emissions, many homeowners are looking for ways to embrace household energy-saving measures.

From harnessing the power of the sun through solar panels to tapping into the efficiency of heat pumps, a myriad of options exist to transform our homes into eco-friendly havens… while also potentially saving money in the long run. 

Over 300 Local Authorities have now declared a climate emergency, the majority setting 2030 targets. From 2025, newly-rented properties will require an EPC rating of C or higher, and by 2035 the UK government aims to retrofit all homes to an EPC B and C standard. According to the Committee on Climate Change, the projected carbon savings required from residential buildings by 2030 is 13 MtCO2e, with 15 million homes needing to be retrofitted by 2030.

In this blog post, we give you an idea of the average costs of the most common energy-saving products, as well as the long-term benefits and potential savings they offer, to help you to make more informed decisions about how to reduce your carbon footprint at home.


What is a payback period?

Put simply, a payback period shows you how long it would take to ‘break even’ on a purchase, by comparing the initial cost to the potential savings. For example, if a product costs £250 and saves you £50 a year on your energy bills, the payback period would be 5 years.

When looking at costs and savings, it’s also important to consider how much each product can reduce your household carbon emissions by. With some products available on finance, the savings can also be more noticeable compared to a lower initial cost. Many products, like solar panels and modern windows, can also increase your home’s value, making them a more attractive investment.

Let’s look at the average costs, savings and payback periods for some of the most popular energy-saving and energy-generating products on the market, to see which would be the best investment for your home…

Energy saving products

Loft and roof insulation: Keeping heat contained within a property increases energy efficiency and reduces heating bills. In an uninsulated home, up to 25% of heat is lost through the roof - and that includes flat roofs!  Costs start from £400, saving up to £55 per year on energy bills, and up to 610kg of carbon each year. This puts the payback period at around 7 years. 

Cavity wall insulation: Post-1930s homes usually have cavity walls, which can be filled with insulation to reduce heat loss. Costs range from £395 to £1800, and can save up to £475 per year on energy bills, as well as up to 1500kg of carbon. The payback period is approximately 3 years.

Solid wall insulation: Where no cavity is available, walls can be insulated internally or externally. Costs range from £8500 to £12000, saving up to £708 per year on energy bills, and up to 1490kg of carbon, with a 12 year payback.

Energy efficient windows and doors: Energy efficient glazing and high thermal performance doors reduce heat loss and draughts. Costs start from £6000, saving up to £210 a year on energy bills, and around 405kg of carbon. This puts the payback period at around 28 years.

Boiler upgrade: Replacing an older boiler with a high-efficiency model saves energy. Costs start from £2750, with energy bill savings of up to £445 per year, and up to 1220kg of carbon, with a 6 year payback period.

Energy generating products

Solar PV/ hot water system: As electricity prices rise, solar panels allow homeowners to generate energy and sell excess back to the grid. The average system costs around £5600 to install, saving up to £480 a year on energy bills, and 1.6 tonnes of carbon. The payback period is around 11 years, or 6-8 years with a storage battery. This doesn’t include the rise in property value associated with installing solar panels, too!

Heat pumps: Heat pumps capture heat from the outside air or ground, and use it to heat a home. Installation costs start at £8000 (less with government grants), saving £6,700 over its lifetime, and 23 tonnes of carbon, with a 12 year payback.

Battery storage: Storing renewable energy in a battery saves it for when demand outweighs supply. A solar battery system starts at £6000, saving around £770 per year on energy costs, and increasing the carbon savings from solar PV, with a 12 year payback.

Wind turbines: Wind turbines convert the power of the wind into electricity - the more wind, the more energy! Average costs are around £31000, saving around £610 per year on energy bills and 1.9 tonnes of carbon. Since costs are currently high, the payback period is around 50 years.

Data for cost savings dates quickly, and does not take into consideration multiple systems working together, like a solar panel system with a battery. Getting realistic data for your property from a supplier is the best way to know how much you could be saving.

Resource efficiency products

Water harvesting: Although not yet suitable for drinking and cooking, rainwater harvesting can provide water for things like laundry and toilets, saving up to 40% on mains usage. A rainwater harvesting system costs from £2000.

MHVR: Mechanical Ventilation with Heat Recovery provides fresh filtered air into a building whilst retaining most of the energy that has already been used in heating the building. Costs average £6450, with up to 50% energy bill savings.

Underfloor heating: Underfloor heating uses convection heat to create a constant comfortable temperature. Costs start from £2300, and is typically a more energy efficient way to heat a home than radiators.

Infrared heating: Infrared heating directly heats the walls, floor and ceiling of a building to build up thermal mass which then radiates back into the room. It has 100% energy efficiency, and costs around £75 per square metre to install.

Financing eco products with a green mortgage

Many homeowners want to reduce both their energy costs and their carbon emissions, but don’t know where to start, can’t afford the products they’d like, or are concerned about potential payback periods. 

A green mortgage is a new type of lending offer that allows you to borrow more during your current mortgage, or at the time of remortgage, to finance the installation of green home solutions.

The idea is that if you're moving into an energy-efficient home or making your property greener, your lender will reward you for that with a better interest rate or cashback on your mortgage.

If you’d like to know more about green mortgages, please contact, and we’ll be able to signpost you to some innovative lenders that we are working with.

CLPM explain the costs and benefits of household energy saving products below...