Non Maintained energency lighting

[Guest yebaws]

We have a guesthouse with about 30 non maintained emergency lights. Current setup is this:

8W T5 flourecent tubes with 2.4v 4Ah Ni Cd batteries.

I'm considering this:

3.6v LED lights with 3.6V 1.8Ah Ni Cd batteries

The actual power consumption of the lights isn't important as they are hardly ever on, but the energy usage when charging is as they are on charge 24/7 and I notice from our energy monitor that our background consumption is quite high.

So my question to anybody who knows about this stuff is what is the difference in energy consumtion between these two batteries when on charge? Is it worth me changing the lights?

Thanks!

[Safelincs]

Hi

I am unable to comment directly to the models you have installed but I checked out both the trickle charge (charge running to the batteries all the time) and the electricity use when the light is on (tubes + trickle charge) on two specific models:

CS8 8 Watt emergency light bulkhead (with fluorescent tube): In maintained operation (always on) it uses 20W, in non-maintained (off until there is a power interruption) it uses 8W

in comparison,

an LED emergency light X-CSE uses 3w in maintained operation and 2W in non-maintained

so quite a significant difference despite both having a 100 lumens light output.

Harry