Introduction to low energy LED lighting
Traditional incandescent bulbs work by passing an electric current through an extremely thin filament which becomes very hot, thereby emitting light. Of all the electricity that goes through the filament, only a small proportion is given off as light, the remainder is wasted as heat (approximately 90%), so these are grossly inefficient, and waste electricity. In September 2012, the UK Government implemented an EU directive to ban the commercial sale of any incandescent lightbulb over 40 watts to homeowners.
There are two types of energy saving light bulb
Energy saving light bulbs convert a far higher proportion of the electricity supplied to them into light (rather than heat) and therefore require less electricity to operate, saving the consumer money on their electricity bill. There are two types of energy saving light bulb, the more modern LED (Light emitting diodes) bulb and the older CFL (compact fluorescent lighting) bulb – as you shall see shortly we are much more interested in promoting LED bulbs as we feel these are the future of low energy lighting
LED energy saving lighting
LED bulbs are comprised of numerous light emitting diodes that together produce light when a current is passed through them. The electrical current excites the electrons inside the diode which produce photons (light) as a result. LEDs are often referred to as solid-state lighting which simply means that the light is emitted from a solid object (a block of semiconductor), rather than as current passes through a filament causing it to glow.
This is the reason LEDs are so much more energy efficient; instead of needing to get incredibly hot to emit light (as is the case with halogen or incandescent bulbs), for an LED to emit light a small current passing through it will suffice. This means that LEDs are far more durable than incandescent bulbs and have an estimated life of 40,000 hours compared to an incandescent bulb’s estimated 1000 hours.
So apart from lasting 40 times longer, why else swap to LEDs? Well because an incandescent bulb needs to get hot to produce light, it converts about 90% of the electricity directly into heat. The LED however doesn’t need to get hot to produce the light, so using just 10% of the energy compared with an incandescent it can produce the same level of light – and that is why they are the future.
LED bulbs require just 10% of the electricity used by an incandescent bulb, but produce the same amount of light.
That means truly significant energy savings in the home – Suddenly replacing just one 50Watt halogen spotlight in your kitchen with a 5Watt LED equivalent could save you over £15 a year (just one bulb!) but produces the same amount of light.
It is important to note that not all LED bulbs are made equal, so please refer to our comprehensive buyers guide to make sure you know what to look for when you are looking to get them for your home.
CFL energy saving light bulbs
Older energy saving lightbulbs are CFL bulbs contain an inert gas and the glass is coated on the inside with a layer of phosphor. When electricity is passed through the gas it emits ultraviolet rays which cause the phosphor coating to glow, thereby providing light. Compared to incandescent bulbs, CFL bulbs use 20% of the electrical power to produce the same level of lighting, and can last about 10000 hours. The issue with them is two fold – firstly they take time to warm up when you switch them on – so they might take a minute or two to start producing required levels of light. Secondly they contain a trace amount of Mercury – so they need to be disposed off in the correct way or they can have a detrimental impact on the environment.
Essentially they should be regarded as the energy saving lightbulb placeholder before LEDs became affordable for consumers. The fact LEDs are now affordable means they should really be consigned to the scrapheap.
Why use LED energy saving bulbs?
Lighting accounts on average about 8% of a household’s energy bill in the UK and therefore cutting this part of the bill is one of the easiest ways to save energy and money in your home. If you look at our 5 watt LED versus 50 watt halogen comparison you will be able to see the kind of savings you will be able to make. In addition LED bulbs last about 20 times longer, so gone will be the days of having to get the ladder out to replace a kitchen bulb every other week!
Energy saving light bulbs in the home
It doesn’t matter if you own or rent your property, or if you live in a house, flat or bungalow, you can save money today by changing the way you use your lights and by fitting new energy-saving lights. Many homes today use a mixture of standard light fittings and halogen downlighters or spotlights (mainly in kitchens and bathrooms). All of these light bulbs can be replaced by either the LEDs – so do it now!
90% energy savings really do add up and they will quickly cover the additional capital cost of the LED bulbs in the first place and as we describe in this blog – don’t wait until your existing bulbs blow before you change them!
You can buy low energy light fittings, which will only take low energy light bulbs, however since many of the new energy saving lights fit in existing fittings there seems little point in doing this unless you are having major renovations in the home. These low energy fittings use a ballast or transformer fitted into the base of the light fitting. It controls the supply of electricity to the bulb, allowing for a small surge of power for a millisecond to light the bulb and then reducing the electricity flow to a very low level. These low energy fittings require a pin based energy saving bulb. This is a different fitting to a conventional bulb but will ensure that the bulbs you buy in future will always save energy, money and the environment.
Another key message – use lights less!
As discussed earlier, energy saving lightbulbs will save you money within your house as they use less electricity to produce the same amount of light. Another really simple way to save on your electricity bill is to turn lights off when you are not using them!
Here are a few tips that will help you achieve this:
- If you are leaving a room, turn off the lights – even if only for a few minutes you will save energy.
- Have a range of different lights within your rooms with different switches, this will allow you to achieve the lighting you need.
- If you have external lights, use a movement sensor that will activate the lights when people approach. This means that they will not be on all the time, and save you power.
- Try and arrange the switches so it’s easy to turn them off, for example have a switch at the bottom and top of a flight of stairs, enabling you to turn them on and off easier.
- An LED bulb has the potential to last between 25 and 40 years, and will use about 90% less energy compared to a similar incandescent counterparts. They also ‘warm-up’ instantaneously unlike the CFL bulbs.
- Energy saving lightbulbs are more durable than traditional incandescent bulbs as they have no filament so will potentially survive jarring where traditional bulbs would get broken.
- CFL lightbulbs can take a small amount of time to ’warm up’ until which point they will not be emitting their maximum light.
- Both types of Energy saving lightbulbs cost more than the traditional type – however these costs will be paid back many times over in energy savings.
- Not all CFLs can be used with dimmer switches – some can, but it is important to check on the packet to make sure.
- CFLs contain small amounts of mercury which is a toxic metal, so they need to be disposed of correctly.
- A recommended energy saving light bulb will cost you £3-£4 compared to about 50p for a normal bulb, while an LED bulb may cost £10 or more.