Is your slow cooker a secret energy-saving hero?

Cooking “low and slow” is a great way to time-shift your cooking. But do slow cookers use a lot of electricity?

Energy efficiency is high in everyone’s minds, thanks to volatile energy prices. Those pennies really do add up. But are slow cookers energy efficient? Will they save you money as well as time? 

After all, even appliances bought for their energy-saving reputation don’t always save energy and money. Air fryers don’t always work out cheaper than using an oven, for example, because it depends on how you use them. 

We’ve asked some experts how energy efficient slow cookers really are, to help you decide whether to invest in one or not.

Slow cookers are great for batch cooking and can make cheaper meat cuts taste deliciousCredit: Shutterstock/Martin Sahlqvist
Slow cookers are great for batch cooking and can make cheaper meat cuts taste delicious

What is a slow cooker?

Cooking low and slow

Slow cooking just means cooking at a low temperature (below 100°C/212°F) for many hours.

You can slow cook in an oven using a lidded dish, just by turning the temperature down low. A standalone slow cooker, with the heat source built into the base, uses less electricity than leaving an electric oven on all daybut how much less, and how should you use it? 


What can you cook?

Time-shifting meals

Slow cookers are great for time-shifting. You put ingredients in the pot at breakfast time, and the slow cooker gently heats them all day, turning them into a delicious dinner. You can cook pretty much everything in a slow cooker – from porridge through to dessert.  

But there are also scientific reasons why cooking low and slow improves certain dishes. The connective tissues in tougher cuts of meat, such as oxtail or lamb shank, break down at low cooking temperatures to release gelatine, for a moist and tender result. 

The cost

Does a slow cooker use a lot of electricity?

Slow cooking is best compared with an oven, not a hob, because hobs are best for quick meals, like boiling pasta or cooking an omelette.

With this in mind, Joanna OLoan, knowledge manager at independent organisation Energy Saving Trust, has compared a slow cooker with an electric oven, looking at costs based on typical meals cooked using each appliance. 

Look after the pennies… 

“Slow cookers typically cost around £0.38* per use – for example, to cook 3.6kg (7lb 14oz) of beef casserole on a five-hour programme,” says OLoan.

“Cooking the same casserole in an electric oven for three hours is likely to cost around £0.48*, so in this case using a slow cooker is slightly cheaper. It could save you money on your energy bills.” 

However, before choosing an appliance, consider what you’re cooking and how many people you’ll be cooking for. 

The good thing about slow cookers is that they are fairly affordable for a kitchen appliance, starting from as little as £20 for a 3L model to up to hundreds if you’re looking at a multi-cooker. 

Featured product

Dunelm Mill Chalkboard Slow Cooker

RRP: £20

Dunelm Mill Chalkboard Slow Cooker

Featured product

Ninja Speedi 10-in-1 Rapid Cooker, Air Fryer and Multi Cooker

RRP: £214.51

Ninja Speedi 10-in-1 Rapid Cooker, Air Fryer and Multi Cooker

Lots of brands also produce them – you can pick them up from your local supermarket or spend the pennies with a Ninja or Green Pan slow cooker. 

Featured product

Green Pan 6L Slow Cooker

RRP: £200

Green Pan 6L Slow Cooker

An oven’s larger size means you can fit a lot of food in at once,” says OLoan. So when cooking larger quantities – for example, when batch cooking or cooking for a large group – using your oven could be the best value for money.” 


Don’t simply compare wattages between a slow cooker and an oven, though, as that could be misleading. Ovens only use their rated peak wattage while heating up, and most of the time when you’re slow cooking in an oven at a low temperature it’s ticking along, using much less energy.

This is particularly the case if it’s an efficient model and you don’t open the door too much. If you have a smart meter, you can see energy costs for yourself while cooking and make an informed decision on savings. 

Will a slow cooker save me money?

Think about batch cooking to save the most money

If you want to save money, look for a slow cooker with the lowest wattage.  

Kathryn Farrell, cookware buyer at Lakeland, explains: “Always check the wattage if energy saving is what you have in mind. This isn’t always the smallest in size, which fools many people! So don’t compromise by using a small slow cooker when you could use a larger one for the same, or only slightly more, energy, and produce more food in one go.” 

Energy efficiency matters, but it’s not the only money-saving aspect of these one-pot wonders. It’s not just the appliance, it’s what you do with it that counts. 

Buy a large capacity slow cooker, which is anything over 6l (around 10 ½ pints) and you can batch cook meals, saving spare portions for another day. Reheating those extra portions when you need them uses a fraction of the energy of cooking from scratch – and it saves you time, too. 

Culinary alchemy 

You can even save money by changing what you cook, by turning affordable ingredients into showstoppers that will feed a crowd. 

“Slow cookers are good for things like brisket and cheaper, tougher cuts,” says Farrell. “I love using mine for making pulled pork when we have friends round, serving it piled high in a bun with jalapeños and sticky sauce. 

But only use your slow cooker for the optimum time needed. “You can save energy by avoiding leaving it on longer than necessary, or use the low setting if you need to leave it on for longer,” says O’Loan. 

Slow cookers also offer convenience. If Friday Morning You is organised enough to put ingredients in the pot and press one button, Friday Night You will be thankful. Piping hot dinner is a gift to yourself. If your slow cooker cuts out a few takeaways, it will pay for itself, and save you money, fast. 

Should I buy a slow cooker?

It all depends on what you like to cook

Know yourself – buy a slow cooker if you know you’ll use it. It will save you money in several different ways, by transforming what you cook as well as cooking it more efficiently.  

But if you’re not the kind of person who will put dinner ingredients together in the morning, look for faster alternatives, such as a pressure cooker. These work like a saucepan but cook food faster – ideal for quick dinners and great for veggies. 

Energy prices change 

Prices correct as of October 2023, based on energy prices under the Ofgem price cap running from October 1 to the end of December 2023. Appliances’ cost per use is calculated using measured energy consumed for each appliance, based on time used for a typical meal. 

Caramel Quin

Written by Caramel Quin


Caramel Quin is an award-winning journalist who has been writing about gadgets and consumer technology since the 1990s, for national newspapers, magazines and websites on both sides of the Atlantic.

Caramel’s pet hates are jargon, pointless products, planned obsolescence and over-complicated instruction manuals. Gadgets should be easy to use, work well and enrich our lives. She wrote The Gadget Show Big Book of Cool Stuff in 2021 and has won numerous awards for communicating hi-tech subjects to normal people. She understands the acronyms and tech specs so you don’t have to.

She’s passionate about the environment and writes about green issues as much as possible too. She’s also a keen allotmenteer, though you wouldn’t know it from the state of her plot.

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