Last week I bought a second hand desk lamp for my workshop at a second hand shop, got a bargain as it did not work, not a problem for a tecnician…
First off changed the bulb as it was a very old filament style, problem solved.
But of course it was old so only took BC type bulbs, the only ones I had were quite old and the compact flurecent tube style.
No problems working light.
But then thought more about it and prefer LED style as consumption is much lower, changed the connection type and changed for the newer bulb, working lamp.
Then thought about electricity use, started with a 60w bulb, changed for a 20 watt tube, then finally its now got a 6 watt LED, with great lighting and ideal.
But what about electricity and my smart meter ?
is it really 6 W, and as I pay my electricity for KWH I have to run my light for a long time before getting to a KW, so how accurate are smart meters for such very low consumption products, in the hall over night I have a night light which is 0.2 W, enough to take the dark corners OK but almost unmeasured.
Not going to get into water meters and the measurements on them but I imagine the same.
I guess the spectrum of the light. Sun light, and bulb light have different, but more or less continous spectrum. Tungsten, and LEDs have non-contigous, somewhat discrete spectrum.
I know this from photography
There are LED lights with high CRI (color rendering index) which produce much better colors for the camera. Those lights have more continous spectrum, I guess.
But thins is just my guess, I hav no scientific background for that
That seems to be continuously sensitive over the whole visible range.
It might be that if the light source only emits in part of the spectrum, and then the solar cell only converts about 30% of that, there is
simply not enough energy being trapped.
