There are huge savings to be made from reducing our carbon footprint. Regular readers will know that I saved in excess of £90,000 in just six years, on a pretty average salary in this way. If you have completed the Three Tonne Challenge, you will have an idea of how much you can potentially save in terms of cash. But you may also be wondering exactly how this might work. So here’s how the annual numbers might break down.

Home energy: £850 a year per household

Average UK spend on gas and electricity is around £1,400 a year, or about £120 a month. In a three tonne lifestyle scenario, this would reduce to £850 a year – giving a saving of £550 a year.

How is this possible?

There are a number of approaches. The GreenBeard family currently spend around £720 on gas and electricity each year. This is achieved through the following highly technical methods:

  • turn shit off. If it’s not needed, it’s not on.
  • wearing beautifully handcrafted woolly jumpers when it’s chilly. Ok, they aren’t always handcrafted, or indeed even beautiful. But you get the idea. We aren’t sitting round in our pants, that’s for sure.

We also spend a further £100-£200 a year on wood for the wood burning stoves. In our house the ground floor is chilly, badly insulated and draughty. Fortunately, that is where the stoves are, and they quickly heat up the space. Upstairs, we rarely need any heating anyway, except on very chilly days.

The lowest-cost, lowest carbon Solution

All of this has a carbon footprint of course, that is still too high to be sustainable. So eventually, we will install solar PV panels, and an air source heat pump that will provided most or all of the heat and hot water we need. This works out as follows:

Solar PV array: Cost £5,000, output 2,500 kWh per year for the next 20 years or so. Annual cost = £250 a year.

Air source heat pump: Cost: £10,000, output 19,000kWh of heat per year for the next 20 years or so. Annual cost = £333 a year.

In this scenario, we would still want to spend £100-£200 on wood for the stoves, to top up the heat from the heat pump on cold days. And because we just like our stove! This gives our annual figure of £850 a year – not to mention a carbon footprint of just 1.2 tonnes instead of 4 tonnes or more.

Vehicles: £2,880 a year per household

Running an average sized, fairly old family car costs around £3,500 each year to do 10,000 miles. Electric vehicles are gaining in popularity as their range increases, and even with higher purchase or lease costs, they are already cheaper to run than their petrol or diesel equivalents. This trend is only likely to continue, as mass production drives efficiencies of scale.

The quick way to reduce this amount, of course, is to cut out some of the driving. 5,000 miles a year reduces this £3,500 to under £3,000, and also makes a significant reduction in carbon footprint.

In the three tonne scenario, however, you would be driving those 5,000 miles in an electric car. Even when leasing a brand new car, this works out cheaper than a petrol or diesel, at £2,880 per year, and a carbon footprint of just 0.5 tonnes instead of 3 tonnes.

Flights: £0 per person per year

If you are a frequent flyer, flying is likely to be a significant cost in both cash and carbon terms. Even cheap flights add up, especially when you add in transfers, hotels, additional charges, and all that ‘duty free’ stuff  you bought at inflated prices in the airport lounge.

You won’t be flying much in a three tonne lifestyle, and the associated cost will also be low as a result. There isn’t really any way yo sugar coat this. The only proviso is that if everything else in your life is ultra low carbon, it would be possible to get a short haul flight in, say every 5 years, or one long haul ‘trip-of-a-lifetime’ every 20 years or so. This would add maybe £200, and 125kg to your carbon footprint per year, and wouldn’t tip you over the three tonne safety limit.

Food: £2000 a year per person per year

Food is one of the largest daily expenses, certainly for families, and a major contributor to our carbon footprint.  You may be choking on your cereal reading that a budget of £2000 a year is going to give you a cash saving. And you are right, it almost certainly won’t. Here’s why.

If we were to stick to around 2,500 calories a day (for an adult), eat little or no meat, and choose predominantly U.K. food raised to organic standards, our carbon footprint would be around 1 tonne of greenhouse gas per person per year. This diet, however, is not currently particularly cheap – hence the £2000 per person price tag. There are of course a host of options within this. Organic is generally considered lower carbon for many foods because it does not allow the use of chemical fertilisers (which use up 5-10% of the global gas supply each year). Yields can be lower in organic systems, however, and there are no reliable figures.

So if you decided to go for a low/zero meat and dairy diet that allowed a healthy 2,500 calories per adult, and was not organic but allowed for very little food waste, then you are probably going to hit 1 tonne of greenhouse gas AND slash your grocery bill at the same time. I haven’t added this option into the calculator, just to be on the side of caution.

Non-Food Buys: £2,400 per person per year

This category includes things like clothes, sports equipment, IT and phones, household goods etc. It is a huge area of spend for many people, who (no offence) on average buy a tsunami of cheap rubbish. All those cheap items add up in cash terms though, and they generally don’t last long or get used much.

The three tonne lifestyle version of this sees us buying fewer items that are good quality and last longer. We don’t buy shit we don’t really need or use. We buy a lot of stuff that is second hand. This is all likely to result in big savings, not to mention a huge reduction in carbon footprint. £2,400 is just £200 per person per month to spend on the things we need. It would be very easy to spend that much just on a new outfit. So this is a challenge. But the rewards are equally huge.

Mobile Phones: £120 per household per year

Smartphones are a constant feature of everyday life, and so what I am about to say will be somewhat heretical: consider ditching ’em. If you add up how much you spend on your phones each month, it is likely to be a lot, especially if you add in insurance, data, calls, and accidents which mean you have to replace that iPhone every year. The cash savings will be huge.

If – like most – you can’t live without your smartphone, then be comforted by the fact that it is very unlikely to be a significant part of your carbon footprint. Reducing your 3G/4G usage by avoiding data use outside of broadband areas and keeping calls to a minimum will bring significant carbon benefits, and possibly financial ones too, depending on how cute you are with your deals. One day there will be a low carbon phone provider, who will run the entire network on renewable energy. Some companies – notably O2 – have already made good advances in this area.

Finance Costs: £0 per household per year

One of the huge benefits of reducing your carbon footprint is that it opens up the opportunity to spend the money you save on getting debt free. In this scenario, you will have no mortgage, and if you have a credit card you will be paying off the whole balance every month. If some of the savings outlined here seem relatively small, then try adding the joys of compound interest and clever investment into the mix. Using money saved on regular items such as energy bills can make a jaw-dropping difference to your finances over a longer period (say 5 to 10 years).

A three tonne footprint is the goal

If we want to have a decent chance of avoiding the worst effects of climate change then we all need to have a three tonne carbon footprint by 2030.

See how close you are to a three tonne footprint – and how much you can save.

Blue button click to calculate your carbon footprint and how much cash you can save


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