GLS large screw bulbs from the Simple Energy Saving Guide to replacing common household bulbs

Replacing large screw GLS bulbs

In this installment of our Simple Energy Saving Guide to upgrading common household bulbs, we are looking at the standard large screw capped GLS bulb.

As there is a huge choice when replacing a standard light bulb, we have put together a guide of the most commonly chosen options to make it much simpler to make your lighting low energy and save you money on your electricity bill.  It is called the Simple Energy Saving Guide to replacing common household bulbs – why not download it now.

GLS large screw bulbs from the Simple Energy Saving Guide to replacing common household bulbs
GLS large screw bulbs from the Simple Energy Saving Guide to replacing common household bulbs

Your current bulb may be using a lot of electricity unnecessarily – you can now easily switch to an LED bulb, which will not only save you money and electricity but as it is instant start and very bright you won’t even realise you’ve switched!  As the chart above shows, the most common chosen replacement for a large screw-in bulb is a 4.6w Omni LED GLS with large screw cap.  The 4.6w omni LED bulbs use less than 5w of electricity, they are instant start – there is no warm up time at all – and they look just like the bulbs they replace.  You won’t remember they are low energy until you see how low your electricity bill has become.

Need Dimmable?

If you have a dimmer switch, you need to use a low energy bulb that says it is dimmable.  Not a problem, we have a dimmable version also available in LED – the 6.6w dimmable GLS LED with large screw cap.

Prefer Daylight white?

If you prefer daylight white (for more information, see below) we currently recommend a 20w T2 daylight spiral with screw cap. This option is slightly smaller than an incandescent bulb so will fit most light fittings, but they are also available in smaller and larger sizes.

More light?

If you want more light, maybe to replace a 100w or higher incandescent bulb then we recommend a 30w spiral bulb with screw cap. This is because they produce the most amount of light whilst still being a good energy saving alternative – in fact the 30w bulb has the same light output as a 150w incandescent bulb.  If you want a lot of light and have a dimmer switch on the circuit then you have two options.  The first is to replace the dimmer switch for a standard switch – if you want a lot of light then you may not really use the dimmer switch anyway.  The second option is to use a 70w halogen GLS with screw cap. These halogen bulbs save 30% energy versus the 100w bulb it replaces and they are completely dimmable, just like an incandescent bulb.

What is a daylight bulb?

Standard household bulbs (and old incandescent bulbs) have a colour temperature of 2700 – 3000K.  This is a yellowish light that is most commonly used in most rooms of your house such as your living rooms and bedrooms.

Daylight bulbs have a colour temperature of 6500K and are visibly very white.  They are ideal task lights, and used to combat seasonal affective disorder (SAD) where people prefer natural bright white daylight colour in their homes.  We have a full range of daylight bulbs available in the Replacement Daylight Bulbs category – why not check them out now »

GLS shape

“GLS?” I hear you say – “what’s that?”

‘GLS’ stands for General Lighting Standard and is simply a way of describing the shape of a bulb – the standard light bulb shape instead of e.g. a candle shaped bulb. For the full range of round bulbs of all types, check out the Replacement Round Bulbs category.

Large Screw Cap

The large screw cap is more common in Europe than in the UK, but as manufacturer make more light fittings for both markets you may find more of these bulbs.  The same large screw cap is used on large reflector spot bulbs such as R63 and R80.  (For low energy replacement options, download the simple guide below.)  The large screw cap is also known or described as ES (Edison Screw), or E27 as it is 27mm in diameter across the screw thread.  If you aren’t sure if your bulb is large or small screw thread then compare against your fingers – if it is more like the width of your little finger, it’s probably a small screw thread.  If it is more like the width of your thumb, it’s a large screw thread.  For more information on screw thread sizes, please see our earlier blog post – E12, E14, SES, E17 – all fingers and thumbs.  For a full range of large screw ES / E27 bulbs, please see our Replacement ES / E27 bulbs category.

Download now

For a complete and simple answer to replacing your common household bulbs, why not download our guide now »

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