Lights on a timer

sevenhills

Can I change my ordinary light switch to a timer?

If I did that, for my kitchen fluorescent tube, how long before I recover the cost of the switch?

Or is there a better way to save money, move to LED?

QrizB

sevenhills said:

Can I change my ordinary light switch to a timer?

Yes.

sevenhills said:

If I did that, for my kitchen fluorescent tube, how long before I recover the cost of the switch?

Forever, if you already turn the light on and off manually when you need it.

If you don't turn it on and off manually, why not? How long each day do you leave it on for unnecessarily, and why do you do that?

sevenhills said:

Or is there a better way to save money, move to LED?

A regular 4-foot-long 36W fluorecent tube, used for 1000 hours a year, will consume 36kWh a year. That's about £10 a year at current prices.

If you replace it with three 6W LEDs you'll save £5 a year.

A fitting to hold three 6W LEDs, plus lamps, is going to cost what, £40? It'll take 8 years to pay for itself.

Netexporter

Change the fluorescent for an LED unit. You'll get more light for half the electricity.

Reed_Richards

You can by LED replacements for fluorescent tubes; I think they use roughly half the power.  So if you replaced a 50 W fluorescent tube with a 25 W LED equivalent you would save 1 kWh worth of electricity after 40 hours of having the light on.  So after something like 130 hours of use you would have saved £1 for each fluorescent tube replaced.  

sevenhills

QrizB said:

Forever, if you already turn the light on and off manually when you need it.

If you don't turn it on and off manually, why not? How long each day do you leave it on for unnecessarily, and why do you do that?

It does bug me that it doesn't get turned off, but I guess the cost of leaving it on is minimal.

Netexporter

You could also fit an infra-red detector so that the new light only came on when there was somebody in the room.

mumf

In our bathroom and kitchen are LED lights with timers. They are approach lights ,and we set them at twenty minutes. If you are there at the time,it simply stays on. Superb. The rest of the house is led too. 

cm4ever

sevenhills said:

QrizB said:

Forever, if you already turn the light on and off manually when you need it.

If you don't turn it on and off manually, why not? How long each day do you leave it on for unnecessarily, and why do you do that?

It does bug me that it doesn't get turned off, but I guess the cost of leaving it on is minimal.

Maybe it's just me, but aren't you in danger of missing the bigger picture?

Yours is probably not the best specific example, but replicate all the different examples of small unnecessary power usage on a population scale - this isn't helping the planet.

There's a lot to be said about if everyone just changed the thought process from "guess the cost of leaving it on is minimal" to "I wonder what impact this would have if thousands / tens of thousands / millions of other people did it".

@sevenhills I'm not personally trying or intending to attack you, I'm just airing the counter thought of small unnecessary usage multiplied by a population mass.

The fact that the light appears to be left on and not just turned on when needed isn't sound thinking by whoever designed it to operate this way...... irrespective of the perceived cost to the individual.

The solution that @Netexporter mentioned or motion sensors are now the norm in many new buildings and retro fit schemes, especially in the commercial use world.

Alnat1

mumf said:

In our bathroom and kitchen are LED lights with timers. They are approach lights ,and we set them at twenty minutes. If you are there at the time,it simply stays on. Superb. The rest of the house is led too. 

20 minutes is a while for a bathroom light to be on every time someone goes for a quick pee that takes 1-2 minutes. Don't know how many in your household but this could perhaps mean an extra 18 minutes of unnecessary lighting being on a dozen or more times a day, 3-4 hours extra? If the lights stay on when they sense you are there, why not set both rooms for 2 minutes?

EssexHebridean

Netexporter said:

You could also fit an infra-red detector so that the new light only came on when there was somebody in the room.

These have an amusing knock-on effect, we have noticed since being in this house. We have sensor activated lighting in the hallway, bathroom, downstairs loo and some in the kitchen. We have always been “lights off when leaving the room” people - but now frequently find ourselves forgetting to do because we’re used to some of our lights turning themselves off automatically! 🤦🏻‍♀️😂

victor2

mumf said:

In our bathroom and kitchen are LED lights with timers. They are approach lights ,and we set them at twenty minutes. If you are there at the time,it simply stays on. Superb. The rest of the house is led too. 

What if somebody is having a nice long soak in the bath? Do they get plunged into darkness after 20 minutes and have to stand up and wave their arms around to get the lights back on?