MPs are to investigate energy price comparison websites following concerns about how they operate.
The Energy and Climate Change Committee said it will examine the role of the websites, transparency of commission received for different energy plans and the level of consumer trust they hold.
It will also look at arrangements for oversight of the websites, for example through the "Confidence Code", a code of practice that governs independent energy price comparison sites.
It said such websites played an important role in helping consumers switch energy supplier by providing comparisons of different energy plans.
But it said in recent months "concerns had been raised about the way in which these websites operate".
The committee asked for written evidence to be submitted by January 14.
Will Hodson, co-founder of The Big Deal website, which was set up last year to help consumers find cheaper energy deals, said: "It's time to clamp down on kickback culture in price comparison.
"For too long, these self-styled 'consumer champions' have taken liberties with a trusting public.
"This investigation is vitally needed and should lead to a more transparent, more competitive energy retail market."
A spokesman for the uSwitch.com comparison website said: "We welcome the committee's inquiry and believe it will provide an opportunity to recognise the important role that price comparison sites play in making the energy market work for consumers.
"We are fully accredited under Ofgem's Confidence Code, which means that consumers can compare tariffs in a fair, independent and unbiased way. We are actively working with Ofgem to update the Code so it continues to provide protection and assurance to consumers.
"We have been calling for all price comparison sites and collective switching schemes to comply with the Code so that everyone operates to the same high standards."
Price comparison sites face probe
This website brings travellers together with people offering a huge variety of places to stay in 190 countries. The spaces range from an air bed in someone's lounge, to a luxury holiday home, so you can search for something to suit your needs and price range.
Before you travel, you need to sign up, search the site for accommodation, contact the host, and if they approve you can book their space. It means, for example, you can book a two bedroom flat in London for £80 a night - which is cheaper per person than a hostel - and much more pleasant.
This service connects people looking for a lift with drivers offering them. In the UK it is only operating in London at the moment - but it is expanding.
The service works through a smartphone app. When you're out and about you can use the app to find a driver in your area, hail them at the push of a button, and track their progress in reaching you.
The rates start at £3 plus 32p per minute for travel under 11mph and £1.75 per mile if you're driving faster. The flat fares include Heathrow to West London for £30 - which is significantly cheaper than a traditional taxi. The service was seen as such a dangerous competitor to London's black cabs that they staged a protest in June.
This is a free shopping app, which lets you scan barcodes when you're shopping, and the app will do a price comparison for the same products in local shops and on websites. You can even buy it online through the app.
It will also let you scan products you have at home and find the cheapest local (or online) stockist.
This started life as a flight search website, and has expanded to include car hire and hotels too. It draws together the advertised flight prices from over 1,000 airlines and travel agents and displays them in one place to save you the legwork.
It isn't perfect, because it relies on the information provided by the agents, so if the agent is tweaking the headline rate and then reverts to a higher price when you enquire, you'll waste a bit of time with the agents. It's therefore worth checking reviews on the cheapest agents that come up before you go any further. The prices drawn direct from the airlines, meanwhile, tend to be accurate.
This is a clever site which is designed to help you get a cheap deal on Amazon.co.uk. It has a few features, which you can use together to make sure you always get a good deal from the site.
The first is the price history charts, which show how the price has changed over time, and how the current price compares. If the price is comparatively low you can just buy at that price. Alternatively, if it has risen recently, you can set a price alert, where you input a price you would be happy to pay, and you will receive an alert when the price drops to this level.
If you use a lot of data on your smartphone, onavo extend will help you dramatically cut the data you get through.
It is a compression app, which works in the background on services like sending and receiving emails, checking maps and browsing the web, and ensures it all uses less data (although it doesn't work on things like Skype or streaming video). It works by ensuring that before any data is sent to your device, it goes through the company's servers and is compressed.
It can cut the amount of data you use by up to 50%, which can help you keep within data limits and save you a fortune. It will also monitor how much data you actually use which will help you pick the most cost-effective plan.
When you call 0800 numbers from your mobile it's not free, and it's usually not counted as part of your monthly inclusive minutes, so you'll be charged extra for the call.
If you install the free 0800 Wizard app, you type in the 0800 number, and it will automatically re-route your call to an 01, 02 or 03 number instead. These cost the same as a standard local call, so will be part of your monthly package. If you don't have any minutes left it will be charged as a standard geographic number.
This website is designed to let you shop around without leaving your home. You can use it in whatever way suits you best. For the dedicated bargain-hunter, you can input everything you want to buy, find the supermarket where each item is cheapest, and spend the absolute minimum.
For those who need a bit more convenience, you can fill your trolley as normal through the site (and use the swap and save button to see if you can save by buying a different size or brand). A basket icon on the right hand side of the screen will show you the cost of the same shop at alternative supermarkets, so you can switch the whole lot over at the click of a button. And there's even a vouchers button you can use before you checkout to see if you can save more. The site claims that you'll save an average of £17 every time you shop using the site.
There are lots of voucher apps and websites out there, but one which is worth a look is vouchercloud. Whether you're shopping, eating out, going to the cinema or going for a drink with friends, you can use the location function of this app to find the best deals on offer near to where you are.
This site has been around for a while, but remains a vital tool. You can search for the cheapest petrol in your area - or the area you are visiting - so you can pay less for your fuel without going out of your way. It's free to sign up and you get 20 free searches a week. There's also a PetrolPrices Pro app, so you can check prices when you're on the road.
10 simple ways to keep your house warm this winter
Price comparison sites face probe
Of course you should make sure the doors and windows are shut properly, but you should also check each one for draughts too. A good old fashioned draught-excluder will stop the wind whipping under the doors, and draught-proofing strips around doors and windows should see off the worst of the chills.
It's not the kind of DIY job that anyone loves, but a quarter of the heat in your home is lost through the roof, so it makes a big difference. Once you've insulated the loft, the roof space will be colder, so make sure you have insulated any water pipes and tanks, and draught-proofed the loft hatch.
If you have thicker curtains, ideally with a thermal lining, you're likely to lose 25% less heat through the window. It's also worth considering curtains over external doors, to prevent heat from escaping. However, make sure you draw them back during the day to make use of any glimmers of sunshine we get.
If you don't have a working chimney but you do have an open fire, then you'll be losing heat through the chimney. If you place a chimney balloon in the chimney and inflate it, it will trap the warm air in.
If you stick the sofa in front of the radiator you'll waste a fortune keeping the back of the sofa warm.
Many people will remember elderly relatives applying tinfoil in a hap-hazard manner years ago, but it doesn't have to be noticeable, and will reflect half the heat back into the room.
Bare, varnished floorboards have been popular for a while, but unless they are carefully filled and draught-proofed, you can lose 10% of your heat through the floor. If filling the floorboards is impractical, a carpet may be a simple solution.
There's no point in heating any rooms you don't use, so turn off radiators in unused rooms, and heat the rooms you tend to occupy instead. Once the spare room gets chilly, you'll need to keep the door closed, and use a draught-excluder to stop the chill spreading.
If your kitchen is the heart of the home you don't need the house so warm during dinner time, because you can use the warmth of the oven to keep you all toasty. Get some baked potatoes in the oven, some soup on the hob, and no-one will notice the rest of the house has grown a little cooler.
It may seem a bit Victorian, but having a woodburner in the fireplace allows you to burn a cheap fuel, and enjoy the heat without the smoke. Burning wood costs less than gas and two thirds less than electricity, so you can stay toasty for less.