Which green tech has the best return on investment?

The Eco Experts

Electric vehicle chargers have the best return on investment

Roof and loft insulation has the quickest break-even point, at 1.4 years

Insulate your home and generate your own heat and electricity – and profit


We all want to go green – to save the planet, to save money, and to futureproof our homes.

Our National Home Energy Survey found 60% of people want to go greener in light of energy bills rising across the country.

The biggest barrier stopping people from embracing renewable products is financial, with high energy bills preventing 43% of Brits from buying green technology – but nearly half of people are still doing it.

Fortunately, this is an excellent time to invest in green tech, with plenty of products offering a higher return on investment and lower break-even point than ever before.

Here are the best eco-friendly products for you to invest in right now.

hypervolt home 2.0

1. Electric vehicle charger

Price
(three-bedroom house)

Total ROI after 20 years

Break-even point
(years)

£1,000

£9,240

2.1

An electric vehicle charger has the best return on investment (ROI) of any piece of green technology, saving the average driver more than £9,240 over the course of 20 years.

This does rely on you having an electric car – though to be fair, all the other products on this list require you to own a house.

Charging at home instead of in public will typically save you £467 per year – and you can save even more if your tariff offers cheaper electricity prices at off-peak times.

And with vehicle-to-grid charging set to revolutionise the electric vehicle market in the next few years, the profits you’ll gather from owning an electric vehicle charger will only increase.

2. Cavity wall insulation

Price
(three-bedroom house)

Total ROI after 20 years

Break-even point
(years)

£1,000

£6,000

2.5

If you have a cavity wall in your home – that is, two walls with a gap in between – you should absolutely get it insulated.

It’ll cost the average three-bedroom house £1,000 to buy cavity wall insulation, and will save you £395 per year.

However, you’ll need to make sure the insulation is installed correctly – otherwise, it could end up costing you more in the long run. Check out which problems to look out for on our page The Top 5 Problems with Cavity Wall Insulation.

Most products will come with a reassuring 25-year warranty, and will usually last at least 30 years without losing effectiveness.

That means cavity wall insulation will save you £10,850 over its lifespan.

3. Spray foam insulation

Price
(three-bedroom house)

Total ROI after 20 years

Break-even point
(years)

£4,075

£6,725

7.5

Spray foam insulation costs £35 per square metre on average, meaning the owner of a three-bedroom house will typically spend £4,075 to insulate their whole home.

With an annual saving of £540, you’ll break even in 7.5 years – and any hard-to-reach areas in your home can finally be insulated.

Like cavity wall insulation, spray foam will usually be guaranteed by the supplier for 25 years, and last for 30 – producing an overall lifetime saving of £12,125.

Considering it’s typically 2.7 times better at insulating your property than fibreglass, this is a worthwhile green investment.

4. Air source heat pump

Price
(three-bedroom house)

Savings after 20 years

Break-even point
(years)

£2,500

£4,891

20.45

An air source heat pump costs £2,500 – as long as you use the Boiler Upgrade Scheme, a government initiative set to last until 2025.

With a heat pump, you can protect yourself against the inevitable rise in gas prices – plus you won’t have to replace your heat pump for 20 years, unlike gas boilers.

Without the help of the Boiler Upgrade Scheme, air source heat pumps would fall to the bottom of this list – but with savings it just about pays for itself over its lifetime. We still think it’s worth it, with all the CO2 you’ll be saving along the way.

The only drawback is that you’ll need large radiators and/or underfloor heating to take full advantage of your heat pump, which may add to your costs.

5. Roof and loft insulation

Price
(three-bedroom house)

Total ROI after 20 years

Break-even point
(years)

£480

£6,620

1.4

Going from no insulation in the top of your home to 270 mm of roof and loft insulation costs just £480 for the average semi-detached three-bedroom house – and it’s more than worth it.

This investment will save you £355 per year, meaning you’ll break even in no time, and continue saving money for decades afterwards.

In a matter of hours, you can add a piece of green tech that’ll make your home warmer and more energy-efficient, without adding complications to your life, as insulation requires very little maintenance.

solar panels on a roof

6. Solar panels

Price
(three-bedroom house)

Total ROI after 25 years

Break-even point
(years)

£7,860

£5,565

14.6

When it comes to saving money by generating your own energy, solar panels are your best choice.

The average three-bedroom house will save £537 per year by cutting its electricity bills in half, and make a further £159 per year by selling excess energy to the grid.

At the end of your panels’ 25-year lifespan, you’ll have typically made a profit of £5,565.

And if you combine solar panels with an electric vehicle and/or air source heat pump, you can get an even better return on investment.

7. Internal solid wall insulation

Price
(three-bedroom house)

Total ROI after 20 years

Break-even point
(years)

£7,500

£700

18.29

Most houses in the UK have cavity walls, but if your home was built more than 100 years ago, you’ll likely have solid walls.

You can usually tell what kind of wall you have by looking at the bricks. If they’re all laid lengthways, you probably have a cavity wall – and if you can see both the long and short sides of different bricks, it’s likely a solid wall.

It’s well worth insulating your walls, and solid walls are no different. It’s a more expensive step than insulating your roof and loft, but it’ll also save you more – £395 per year, on average.

Your solid wall insulation should last around 30 years, giving you a total return on investment of £4,350.

8. Infrared panels

Price
(three-bedroom house)

Total ROI after 20 years

Break-even point
(years)

£7,800

-£980

22.87

Infrared panels are the future.

Their ability to heat people and objects instead of air makes them more efficient than gas boilers, and they’re easy to install – just attach a panel to your wall or ceiling, and plug it in.

Their major drawback compared to gas heating is infrared panels won’t provide you with hot water, but this issue can be solved with an electric immersion heater or hot water cylinder – which we’ve included in the price above.

9. External solid wall insulation

Price
(three-bedroom house)

Total ROI after 20 years

Break-even point
(years)

£11,000

-£2,800

26.8

This may seem like a strange addition to the list at first, considering you’ll still be in the red after 20 years.

Thankfully, external solid wall insulation typically lasts 30 years, meaning you’ll make an overall profit of £850 on your investment.

And between now and then, you’ll be able to enjoy a warmer, quieter home with fewer draughts.

Plus, external solid wall insulation allows you to refresh the outside of your walls, avoid disruption and mess inside your home, and add insulation without reducing your home’s size.

Which green tech has the best break-even point?

Roof and loft insulation has the best break-even point, at just 1.4 years.

And considering this handy addition usually lasts for 40 years with little to no maintenance, you should seriously consider taking the leap and getting insulation as soon as you can.

A relatively small investment will ensure you reap the rewards for decades to come, saving a total of £13,720 by the end of your roof and loft insulation’s lifespan.

Written by:
josh jackman
Josh has written about eco-friendly home improvements and climate change for the past four years. His work has been displayed on the front page of the Financial Times, he's been interviewed by BBC One's Rip-Off Britain, and he regularly features in The Telegraph and on BBC Radio.
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