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With high trees and bushes either side, our driveway is spookily dark at night. The Victorian style street lamp at the side hadn't worked in the 6 months since we moved in, so I had a good look at what was going on.
The bulb in it had blown. It was plugged into a bayonet extension light sensor which switched the light on at night.
Bearing in mind a 100 watt bulb running during the winter would be on for 15 hours, I decided to look into greener LED alternatives.
The most powerful bulb I could find was the Philips Endura Dimmable 12 watt, equivalent to 60 watts. From Amazon, it cost an eye watering £38.70 delivered.
Manufacturer's Details
Type of Bulb : LED
Cap Type : B22
EU Energy Efficiency Label : A
Luminous Flux : 136 lumen
Wattage : 12 watts
Incandescent Equivalent : 60 watts
Colour Temperature : 2700 Kelvin
Average Life : 25000 hours
Just like all the B22 and E27 ('standard' size) LEDs I have seen so far, the Philips weighs more than a conventional bulb and feels well made.
It's been working outside in the Victorian lamp now for a couple of weeks with temperatures being sub zero. Since it's getting dark at about 4 and light at about 8, there are a solid 16 hours of continuous use every day.
Am I satisfied with this LED bulb? Well honestly, not completely, but then that's more to do with how I'm using it than the bulb itself.
I think a bulb like this is designed to hang down from the ceiling (optionally working on a dimmer switch) and in that situation, it would do it's job very well.
However, because the bulb is upright in the Victorian lamp, the light output is somewhat disappointing.
As with a lot of these LEDs, the nature of the bulb means the light doesn't shine down (towards the base of the bulb) as much as conventional bulbs. And it's in situations like this, a 10 foot high lamp, that we need the light to shine down. So it doesn't cast as much light onto the driveway and at 12 watts (the equivalent to a 60 watt normal bulb), it's also probably not quite powerful enough in general.
Having said that, the bulb has worked reliably for several weeks including during the sub zero, snowy weather we've experienced.
Let's compare the overall cost of the Philips against a 50 pence, 60 watt incandescent bulb.
Using the attached bulb cost calculator (Excel spread sheet):
Period to examine: 5 years
Cost of your electricity: £0.10 per kWh
Daily hours of use: 12 hours per day
Bulb type Incandescent LED
Power in watts 60.0 12.0
Individual bulb cost £0.50 £38.70
Avergage Lifespan in hours 1000 25000
Number of bulbs needed 22 1
Total Purchase Cost £11.00 £38.70
Running cost £131.40 £26.28
Total cost over 5 years £142.40 £64.98
Using LED will save us approximately £77.42 over 5 years
Assumptions:
There is no change in the cost of bulbs or electricity over the entire period. If the cost of either change, as they probably will, the final figures will be different
The lifespan of the bulbs is similar to the averages quoted |
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26-11-2019 04:16:25