LED Light Bulbs & Cap Types

There is now an LED alternative to all of the traditional incandescent, halogen and CFL (compact fluorescent lamp) light bulbs used in households. LED light bulbs offer energy savings of around 80% when compared to halogen and last around 30 times longer. 

In the lighting industry the correct term for a light bulb is a lamp. Light bulbs that have caps like GU10, bayonet cap and Edison screw etc are known as retrofit lamps. They can be easily replaced without needing to call out an electrician. In comparison many of the downlights we offer have integrated LEDs which are non replaceable.

Cost Savings

Although the main savings to be made by switching to LED is from energy consumption, if you compare purchasing 1 GU10 LED at a cost of £5 to 30 halogens at £1 each, you can make a saving of £25 per bulb over the lifetime of the LED. This saving is based on just one lamp!

According to the Energy Saving Trust, lighting accounts for 18% of the overall electricity consumed in an average UK household. By converting all of your existing lights to LED light bulbs you can reduce your overall electricity bill by around 14%. In real terms an £80 per month electricity bill could be reduced to £68.80, making a saving of £134.40 per year!

Longer Lasting

Halogens last for only 1,000 hours and good quality LEDs like the Philips Master Value range last for 30,000 hours but what does this equate to in years? If you were to keep your lights switched on permanently 1,000 hours would only last for 41.6 days but an LED would last for 1250 days or 3.4 years. However, there aren't too many people who leave their lights on in the daytime and when they're asleep so if we base our calculations on 3 hours per day, LED light bulbs should last for an amazing 27 years.

When you're making an investment in LED lighting it's always better to go with recognised brands like Philips, Aurora and Megaman. These brands are now in their 4th and 5th generations and are manufactured to higher standards using better quality LED chips and improved heat sinks for faster heat dissipation.

Cap Types & Selection

Here are the most popular LED light bulbs and cap types used in modern day lighting and available on Downlights.co.uk. If you're looking for a low energy alternative remember to compare the lumens and not just the wattage. Lumens represents the brightness, ideally you want the lowest wattage light bulb that has the highest amount of lumens, this is known as efficacy and is calculated by the lumens per watt (lms/W).

Bayonet Cap (B22 or BC)

Bayonet caps are a UK thing and it's unlikely that you'll find any overseas apart from countries like Cyprus and British territories like Gibraltar. BC caps are mains voltage with 2 pins and have a diameter of 22mm. The most well known wattages are 60 and 100 watt which would now be replaced with 7 or 13 watt LEDs. A 60 watt light bulb produces 800 lumens and a 100 watt light bulb produces 1500 lumens, these wattages are now banned in the EU.

This style of light bulb is known as a GLS which stands for General Lighting Service and is also available in a screw cap.


Edison Screw (E27 or ES)

Edison screw caps are also known as ES, they are more common in America and Europe but are becoming more popular in the UK with outdoor lights and European brands of light fittings. Known as E27 as they have a screw in cap with a 27mm diameter. Apart from the difference in cap types, the E27 is identical to the B22. They are mains voltage and are available in various wattage types.


Small Edison Screw (E14 or SES)

Small Edison screw caps are also known as SES and are mainly used in table lamps, wall lights and chandeliers. They have a screw in cap with a 14mm diameter. They are mains voltage and are available in various wattage types mainly alternatives to 40 and 60 watt.


Small Bayonet Cap (B15d or SBC)

Light bulbs with this cap are identical to E14 but have pins on each side. This cap is becoming less popular and many manufactures and choosing not to produce an LED B15d version. 



Originally designed for use with halogen, the GU10 has become our most popular choice of cap type for LED lighting. The GU10 cap is mains voltage and has two stubby pins that need to be twisted in and out of the light fixture. It's known as a GU10 because their is a gap of 10mm between the centres of each pin.


MR16 (GU5.3)

Before the GU10 cap was invented your only option of producing a clear white lighting effect with halogen using recessed downlights was to go with MR16 low voltage. They operate on 12V ac an require a low voltage transformer, some MR16 LEDs will work with existing transformers but some require an LED driver. An LED driver is different to a transformer as it provides a DC (direct current) voltage, compared to a low voltage transformer that is AC (alternating current).

This type of cap has 2 sharper pins that have a gap of 5.3mm between them. 


Integrated LEDs

Integrated LED light fittings were introduced to the lighting industry in 2010 with the first wave of integrated LED downlights. Although you will be familiar with the light bulbs and caps listed above you may not have been introduced to integrated LEDs. In short, integrated LEDs are complete fixtures not bulbs. They are a more technologically advanced style of light fitting.


They're not classed as light bulbs as they don't have caps, integrated LEDs are light fittings containing a fully integrated LED light source that is built directly into them, the LED is usually non replaceable. The idea behind these types of fittings is that because the light fitting is specifically designed around the LED light source it can provide more light (lumens) while maintaining a longer lasting and more reliable alternative. Integrated LED lights are usually mains voltage as they are also fitted with an LED driver.

Many consumers still don't like the idea of integrated LEDs, mainly because if they do fail you need to get an electrician to disconnect them and swap them over as most of them are wired into the mains. However some lights like the Click Inceptor Micro or Inceptor Max shown below have a plug in Flow Connector which easily plugs away from the lighting circuit.

It is widely predicted that the retrofit lamp market will begin to decline by 2020 in favour of integrated LED fittings. This is already happening with downlights and as more and more fixtures such as ceiling and wall lights become available the integrated LED market will continue to grow. In the EU the integrated LED market is currently worth £8 billion (as of 2015). CLICK HERE to read more from Megaman Lighting's Adrian Kitchen.

Megaman have recently introduced the UK's first integrated downlight that also has an interchangeable LED, the best of both worlds! This downlight is know as the VersoFit:


Earlier in 2015 the European Commission (EC) decided to delay making the decision not to ban halogens until 2018, but this now only relates to GLS light bulbs and candle style lamps. In October 2015 they have now ruled that directional halogens such as the 50 watt GU10 will be banned in September 2016, read more from Lux Magazine.

At first the EC didn't believe that lighting manufacturers could cope with the demand, you can read more about this hereI believed this was a mistake, but I am not one to stand in the way of progress and don't believe in delaying the inevitable. I've also got faith in the UK's Lighting industry and who in their right mind is going to install a 50 watt halogen after reading this article?

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