The Sustainable Living Calculator analyses the costs of 20 everyday household items including apples, pasta, shampoo and toilet roll.
To buy every item on the list in the ‘greenest’ possible way would cost a family of four £5,915 over a year.
But the equivalent shop, based on non-organic items, or cheaper plastic-wrapped goods than fresh alternatives, would cost the same family just £3,151.
This makes green shopping 87 per cent more expensive – or almost £2,000 – over the course of the year.
A bag of standard carrots costs an average of 75p from Tesco, with their organic equivalent adding nearly a fifth of the price, up to 95p.
Similarly, a pack of supermarket-own brand bacon normally costs just £1.95 – with rurally-raised bacon from online retailer ‘Perfick Pork’ selling for as much as £4.99.
The Sustainable Living Calculator, developed by money.co.uk, also looked at other expenses such as energy and holidays.
Salman Haqqi, personal finance expert at money.co.uk, said: “There are certainly more pros than cons when buying green.
“As with all things you should always budget for your outgoings and on occasion you might be spending a little more money to be more sustainable, but the overall impact you can have by making small changes is surely worth it.
“By avoiding products wrapped in plastic, eating seasonally, and avoiding items or travel that has a large carbon footprint, consumers can really have a positive impact on our planet’s future.”
Separate research by money.co.uk revealed 43 per cent of adults are happy to spend more on eco-friendly choices if it lessens their impact on the environment.
Thirty per cent try to buy local produce, and four in 10 do their best to avoid plastic packaging where they can.
And more than six in 10 of the population now use a reusable cup whenever they buy a coffee from a café.
But four in 10 would make more of an effort to be eco-friendly if it didn’t end up costing them more.
However, 42 per cent admitted they worry about the impact their current personal shopping choices have on the environment.
More than half of Brits think it is important that their energy is from a renewable source.
But just 26 per cent said they’d opt for a renewable energy supplier if it cost more.
Matthew Agarwala, environmental economist at the Bennett Institute of Public Policy at the University of Cambridge who helped develop the calculator, said: “I have a lot of sympathy for consumers who want to do the right thing but just don’t know how their shopping choices affect the environment.
“That’s why tools like these can be so useful when they are backed by sound scientific evidence.
“Sometimes what looks like a quick and easy bargain today often comes at someone else’s expense because it imposes much bigger costs – environmental, social, health – on others.
“For instance, ‘cheap food’ is a myth. Whether it’s the consumer, the planet, or the farmer, someone always pays.
“But there’s loads of reasons to be optimistic. It is so encouraging to see Britons taking the environment seriously.
“From school strikes, to a climate change leader’s debate, to the Attenborough effect, the British people are tuned in and engaged.
“Tools like this can help us make better day to day choices, and together we can demand the kinds of policies that make going green easier and more affordable.”
The new Sustainable Living Calculator can be found at: https://www.money.co.uk/content/sustainable-living
THE COST OF GROCERIES – ‘GREEN’ vs ‘NON-GREEN – PRICED FROM TESCO.COM AND OTHER RETAILERS
ITEM ‘NON GREEN’ COST ‘GREEN COST’
Bread £1.05 £1.50
Cereal £1.39 £3.42
Rice £1.80 £2.97
Pasta £1.26 £2.30
Chocolate £1.50 £2.57
Apples £1.75 £2.35
Bananas £1.50 £1.10
Oranges £1.50 £2.43
Carrots *1kg £0.75 £0.95
Onions *1kg £0.95 £1.65
Peppers (3 pack) £1.20 £3.00
Bacon £1.95 £4.99
Chicken *2kg £3.70 £7.46
Beef *1kg £5.95 £11.23
Sausages *6 Pack £2.00 £3.00
Eggs *6 pack £1.00 £1.80
Milk *1 Pint Semi Skimmed £0.50 £0.95
Cheese £2.25 £3.70
Coffee *200G £2.14 £3.85
Yogurt £0.90 £1.50
Sanitary Products £1.90 £3.49
Shampoo £3.30 £8.00
Soap £0.80 £4.95
Deodorant £1.80 £9.95
Butter £1.50 £2.00
Olive oil £3.00 £3.25
Multi-surface cleaner £2.50 £2.20
Fish £2.80 £3.50
Toilet Roll *9 roll £3.35 £4.99
Ice Cream £2.00 £3.89