From the end of this month halogen lightbulbs are to be removed from the market across Europe, with households expected to switch to LED lights – which cost more but last far longer and use much less electricity than energy-hungry halogens.

According to Philips, the lighting manufacturer, the average UK household has 10 halogen bulbs and uses them for 2.7 hours a day. If that is correct, then hundreds of millions of halogens are going to have to be replaced. So why are they heading for the scrap heap – and what do you have to do?

What is the ban? Old-fashioned incandescent bulbs were the first to go, in 2009, and in 2016 the phased removal of halogens began in an EU-wide effort to improve energy efficiency and cut carbon emissions. Halogens are hugely wasteful of energy – the Energy Saving Trust estimates that the typical halogen uses £11 of electricity a year while a replacement LED would use only £2 worth. What’s more, halogen bulbs typically fail after about two years, while LEDs should last for around 15 to 20 years on the same usage.

Do I have to replace all my halogens now? Don’t panic, you won’t have to whip them all out for fear of an EU fine. Replace with LEDs as and when the old halogen bulb expires.

LED bulbs are super efficient and last longer. Photograph: Jeff Blackler/REX/Shutterstock

Will shops stop selling halogens on 1 September? No. They will be able to sell their existing stock but won’t be able to reorder more. So if you are obsessed about keeping your halogens, then there’s still time to buy some. But you’ll be throwing money away in the long term.

Will the LEDs fit existing light sockets? In most cases, yes. You can buy “bayonet” or “edison” (screw-type) LED bulbs at most outlets. But there may be a problem if you have halogen lights fitted in your ceiling (especially common in kitchens) which are connected to transformers. According to Philips:“The low wattage equivalent LEDs sometimes mean some transformers cannot detect that the light is actually switched on and therefore lights can flicker. In this case it is worth seeking advice from your electrician.”

Is this a total ban? There remain a few types of halogens that are outside of the EU ban, for now. For example, there are some oven lights that are halogens that will still be permitted for sale, as well as some “capsule, linear, low-voltage reflector bulbs”, says Philips.

How do I know which LEDs to buy? A generation brought up on bulb brightness expressed in terms such as 100w or 60w has to learn the new vocabulary of “lumens”. Wattage measures power or energy, while lumens measure light output. Broadly speaking, a 60w bulb gave off around 700 lumens, while a 100w one is equivalent to more than 1,300 lumens. But stores such as John Lewis still label LED lights primarily with watts; it says its 8.5w “classic” LED bulb is equivalent to a 75w incandescent bulb, while a 13.5w LED is equal to a 100w old-style bulb.

How much do they cost? More than incandescent bulbs. At B&Q, “Diall” LED bulbs offer 1,520 lumens (it says that is equal to the old 100w bulb) and cost £8. But remember how much less electricity they use and how long they last. If households replaced 10 halogens with 10 LEDs, the long term savings are equal to about £112 a year, says Philips.

This is an EU thing. Can’t we just ignore it because of Brexit? The initial ban caused some outrage. James Delingpole, the Daily Telegraph columnist, said he was “incandescent with rage” at “another piece of typically, bullying, ill-thought-through piece of EU legislation”. But lighting manufacturers have made it clear that they are not likely to produce special bulbs for the UK market alone. And we are still in the EU, so EU rules apply. A spokesperson for Philips says: “As the UK is still governed by EU ruling and we are still within the EU at the time of the imposed ban we cannot ignore the new regulation.”