How to reduce your carbon footprint - and save money

Brenda from Trust u3a's Countdown to COP27 group shares things the group has tried to cut down their carbon footprint

How to reduce your carbon footprint – and save money!

Eight stories from u3a members who have all made changes to their homes and their lifestyles to reduce their carbon emissions and /or to save money. Some also found that there were health benefits.

Improved insulation

Improving your insulation is probably the most effective step you can take. Some insulation schemes are very extensive/expensive; others less-so. Without very good insulation, other measures are likely to have limited success.

Kate from Teesdale u3a lives in an old stone building in a remote area with no gas. She has upgraded her heating from an oil boiler to solar PV panels, batteries and heat pumps and has made improvements to the insulation of the whole house.

Between summer 2020 and the end of 2022, Kate has been stripping back the interior for full insulation. This has caused huge disruption but was essential because of the low-heat output of a renewable energy system.

To make a stone house in an exposed upland location more energy efficient and cheaper to heat, Kate is eliminating cold and damp in walls and floor; repairing the sagging and leaking stone slate roof; and replacing old draughty windows and doors. Her Energy Performance Certificate is now recalculated at ‘A’ (unheard of for local properties with solid stone walls, 18” thick). Costs are difficult to estimate as this is a large and complex renovation.

Kate cautions: The advice and expertise of an MCS (micro-generation) certified company has been essential; digital controls mean no worries about fuel supplies and manual operations.

Under floor insulation and heating

Hillary from Edinburgh u3a is in the early days of upgrading his insulation. The ultimate goal is to reduce heat loss sufficiently so they can use a better and smaller heat pump than is required to heat the house in its present state. Costs are ongoing.

The under floor insulation uses Icynene foam. With only a 50mm cavity, the existing cavity wall insulation not good enough - and not present in a couple of places. Hillary says they have lots of draughts and poorly implemented insulation without sufficient draught control in the loft space and attic rooms.

Currently, Hillary is experimenting with internal wall insulation on wall cold, north facing rooms; and secondary glazing using Perspex sheet on north facing windows. They plan to buy new doors for side and back and are considering and doing calculations for permanent internal wall insulation for north facing rooms and for improving loft insulation.

Hillary is also experimenting with secondary double glazing.

David from Lichfield u3a has also invested in insulation, for both environmental reasons and to add to the value of the house. It comprises high performance argon filled triple glazing on most ground floor windows including the front door, new thick under-floor insulation of the ground floor and a warm roof with insulation under the tiles as well as 25cms thick insulation over the ceiling below the attic.

The conservatory has triple glazing on the windows and doors, and double glazing of the roof panels, with under-floor heating to maintain the ambient temperature at least 15C, with an air source heat pump with an 8kW output to quickly bring the room temperature up to 21C when needed.

Nick Ward, from Ruthin and District u3a supervised the installation of internal wall insulation and an air source heat pump in his son’s house in January 2022, while his son was abroad. This was to reduce heat loss, improve heating, and combat damp through the use of low carbon technology and to reduce heating costs.

Internal wall insulation

The cost of the insulation and low-energy extractor fans was fully funded by a means-tested grant scheme. Nick’s son feels that the steps have been very successful. Meanwhile, the salt container in the kitchen is no longer soggy and the olive oil is no longer going thick from the cold! They also plan to spend an extra £150 to add to the existing insulation in the roof space.

Air Source heat pump

Back to Nick’s son, from Wales: Air-source heating system was installed, including radiators and a new hot water tank (which has excellent built-in insulation) and pressurised plumbing. There was a shortage of space to fit in all the expansion tanks, etc and the engineers found a neat solution by putting most of these in the roof space. The heating will be partially subsidised through the Renewable Heat Incentive (since closed from the end of March 2022). This will pay back about £7k of the cost over a 7 year period. This incentive is now replaced in England and Wales with a capital grant, which can pay up to £6k. This is called the ‘Boiler Upgrade Scheme’ (BUS for short) and can be used to help fund the replacement of any fossil fuel heating system, i.e. gas, oil or direct electric, with air source, ground source or biomass boilers. To be eligible you must have an EPC (Energy Performance Certificate) and loft and cavity wall insulation must have been installed.

Kate from Teesdale has two air source heat pumps because ground source (her initial preference) would have meant drilling two costly bore holes in the garden.

Ground source heat pump

In his own home, Nick (Ruthin) installed a ground source heat pump in 2017, to follow an earlier installation of PV panels. The purpose was both to save money (eventually) and to generate low carbon electricity and energy efficient heat. The capital outlay for both was high, but the costs will be fully paid back eventually. The heat pump and plumbing (including ½ km of pipes in an adjacent field!) totalled £19k; costs should be less now.

Nick says that the heat pump was made easier for them as they have a field for trenching heat pump pipes, rather than vertical drilling.

Nick feels this has been really successful. They can switch off the heat pump for half the year. Although it heats the domestic water when it’s on, in the sunnier 6 months of the year, surplus (free) electricity from solar panels heat the water. Nick also has a clever gizmo that diverts surplus power to the immersion heater, so they NEVER switch on the mains supply to the immersion. And included in the heat pump scheme was a larger, well insulated tank, so they have a plentiful supply of hot water. The water tank is in effect an energy store (they have not yet installed batteries, but are interested in the possibility).

Solar (PV) panels

Brenda from Cotgrave and District u3a purchased 20 PV Panels in May 2021 – output 6kW. This was primarily for environmental reasons; the Feed In Tariff by then was almost insignificant. The cost was around £8K which included a diverter that heats the domestic hot water, once all appliances have been provided for. As the first year draws to a close, it looks like a saving of approximately £500 will have been made – a combination of: electricity not bought from the National Grid; free hot water whenever the sun shines; reduced gas bills when the sun shines (as a convector heater is used then); plus a small feed in tariff. Software on Brenda’s computer – and her phone – enables her to monitor energy use and production and helps her to choose whether or not to run appliances or heaters.

As energy costs rise, the amount saved will only increase. Brenda is now considering fitting battery storage (see Idris, below). Eventually, she is likely to buy an EV which will be charged from the panels but is currently running a hybrid vehicle which is likely to last for some time.

Battery Storage

Idris from Pershore and District u3a has this year installed a battery pack to maximise the benefit of his existing solar (PV) panels. He did this to reduce their carbon footprint and save money by further reducing electricity drawn from the National Grid, at a cost of around £4,000.

Without battery storage, overnight and during dull periods power is bought from the grid. A battery means that daytime power produced by the panels in excess of immediate household need goes to the battery where it is stored until subsequently needed during dull periods and through the night. Minimising the power drawn from the grid, electronic-switching controls the flow of power 24/7 between the panels, the household devices, the battery and the grid. Savings in the use of grid power will vary with the season and the capacity of the battery.

This system also comes with software demonstrating the flow of energy in and out of the house.

Kate (Teesdale u3a) comments that batteries in her attic mean that some days the system is feeding surplus electricity back into the grid.

Electric Vehicles (EVs)

Hillary from Edinburgh u3a decided to invest in an electric vehicle (EV). He has subscribed, at £600 per month, into a subscription service to try out a range of EVs. His reasons for trying an EV were to reduce his carbon footprint, and find out if they would get on with an EV, and whether electric cars are yet viable in Scotland.

The scheme avoids long term commitment, lets you try different cars and costs little more than the monthly cost of ownership. Hillary feels that it’s not time to buy yet if you don’t need to. So far he has tried out a VW ID-3 and a Hyundai Kona.

Hillary likes the EVs’ quietness and smoothness, being easy to drive and having good acceleration because no gear changes. He has found that he needs to plan trips and charging carefully and be willing to wait while charging at a charging station. Typically, it takes an hour to charge 20-80% at a fast charger or overnight at home.

Hillary comments: “Nothing to be afraid of, lovely to drive but need to plan!”

Electric bike (e-bike)

Clive Teague from Odiham District u3a and Farnham u3a is a great fan of electric bikes and has now owned two; his first bike was sold on to another u3a member. As well as a desire to use the car less and reduce his carbon emissions, Clive was also interested in improving his health. As Clive points out, petrol engines are at their least efficient on short journeys so using an e-bike for these maximises the savings per mile on transport costs. In 2019 Clive bought his first e-bike. He says that his hybrid e-bikes have exceeded his expectations both as practical transport and as a leisure pursuit. He enjoys cycling immensely as it gets him out in the fresh air for some exercise, avoids the gym and has the lowest carbon footprint of any transport.

Clive’s first e-bike cost £900 and was then sold. The replacement was £2,000. Clive says “As I live at the top of a steep hill, returning to cycling after a 50 year gap seemed impractical. An e-bike closed that gap and by only using the electric motor on hills when necessary, I can ensure that I exercise at a safe level. My latest e-bike has a comfortable range of 40-50 miles providing I keep the settings to Touring rather than Sport or Turbo!

“The saving in my transport carbon emissions has been welcome. I particularly enjoy off-road cycling and ride out with my local u3a Farnham cycling group. I take my e-bike everywhere and I believe it has now become my best friend!”

The ultimate way to save carbon and money: sell the car!

Ann MacGarry, Machynlleth u3a saved money and carbon and not only did it cost her nothing, but she made savings instead! Despite living in rural Wales, this was made possible by setting up a car share scheme. Now that’s ‘thinking outside the box’!

Over the years the many users have walked, cycled, used buses and trains and then been able to get hold of a car when they really needed one. Recently they also acquired an electric car in a linked share scheme. Like Clive, Ann discovered that in addition to carbon reduction and saving money, this was also a great way to reduce stress: another health benefit.