Simply have a rechargeable battery built in to the light bulb that is bypassed when there is power and trickle charges if required.

Then if there is a power-cut, have a little switch on the base of the bulb that switches it over to the built in battery.

Obviously, you'd only have a couple in your house - extra features would be to glow red with a mechanical voice declaring 'Switching to auxiliary power!'
-- noblea, Jul 26 2006

SmartCharge 2.0 | Indiegogo http://igg.me/at/smartchargelight
[xaviergisz, Jan 22 2016]

This is how emergency lighting works, except that the battery is built into the fitting, rather than the bulb.
-- angel, Jul 26 2006


there are actually emergency lights now that are a glow in the dark coating on the inside of the bulb. when the lights go out, the bulbs are fully charged from use, and are ready to be unscrewed and used as portable torches.
-- tcarson, Jul 27 2006


Probably quite bakeable with an LED/LED cluster and small battery and regulator. Wouldn't even have to modify the existing fitting at all. Just use red LED's. or red flashing LED's.

I like it.

+
-- Custardguts, Jul 27 2006


I appreciate that this idea is hardly revolutionary, but the fact is that my house experiences many power cuts and i'd like a simple solution to it; a smoke detector that has a little light on it doesn't help me much - i like the glow-in-the-dark bulbs idea, except that i actually want the light to go off when i switch it off, and only light up when there is a power cut...
-- noblea, Jul 28 2006



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