One of the reasons that many people are put off installing renewable technologies such as solar PV is that in order to generate enough to power a typical house, you need a lot of it, at fairly vast expense. Being simple peasant folk, that’s not an option open to us, so the solution? Use a lot less in the first place and avoid the need for lots of PV.
The simplest way to use less electricity is to change your light bulbs. The energy saving ones are fine, but they suffer from slow startup, can be a bit on the dim side, and it turns out that they are full of hideously toxic things that are near impossible to get rid of.
So, the solution? LED’s. For a long time they have been used as decorative lighting, as they just weren’t bright enough, but things have changed. As they are very low wattage – 5 watts or less, we decided to experiment by buying a few of different sizes and colours to see what would work, and as it turns out there’s a fair bit of difference. We have some 1.5 watt ‘cool’ ones, and they are distinctly blue. Great for reading under as it turns out, but not good for lighting a room. At the other extreme, we have 5 watt ‘warm’ ones, which are the newer SMD type. The difference is amazing – they are definitely 60W equivalents.
Here’s the difference in colour –
And as you can see, they are very different from each other. When mixed you get a very good light indeed. So – the 22 bulbs we have in the house would consume approximately 1300 watts using traditional light bulbs; around 600 watts using energy saving bulbs, and amazingly, just under 70 watts using LED’s.
If you’re wondering how that translates into the amount and cost of solar PV that we realistically need to drive the lights, then consider that solar typically produces half the energy that it is rated at, and currently costs about £1 per watt. That means that changing our light bulbs requires only £140 worth of solar pv as opposed to £2600 to drive the equivalent in traditional light bulbs. If you’re paying an electricity company then it makes even more sense to switch. The bulbs themselves aren’t cheap – £4 – 7 each depending on the wattage, and more for bayonet fitting ones, but they should last a long, long time, and most are guaranteed.