Low Energy Light

[Andrew Gabriel]

You can increase output at the expense of life.

3000 hours is the typical figure manufacturers use for life of a car when specifying minimum lifetime of components which they don't normally expect to need replacing. Night time driving is probably typically less than half that. Producing a high output LED with a design life of, say, 1000 hours should mean you can significantly overrun it, although achieving a reasonably stable output over that period would need to be taken into account. You could easily include reliable forced-air cooling for such a short lifetime, and where noise isn't an issue. (Reliable maintenance-free forced-air cooling isn't achievable for the 20k+ hours life claimed for many LEDs.)

[Mike]

They would say that, the reality is they were also nicked from Joseph Swan.

The list of American inventions not nicked from someone else is many times shorter than the list of famous Belgians.

[Appelation Controlee]

The truth is probably more mundane than that - most "inventions" aren't lightbulb moments (yes!), but developments. They told us at school that James Watt invented the steam engine, but he didn't, of course, he developed a dramatically improved one.

[Neil Williams]

There are some used in Den Haag, NL for exactly that purpose (or more specifically pavement/cycle track lighting). They seem to be a mix of white and yellow LEDs. They seem to work reasonably well, though suffer from the very monochromatic nature of LED light, and I expect they are cheap to run and maintain.

Neil

[Adam Aglionby]

Edison actually bought the idea, well a U.S Patent, from 2 Canadians for the not inconsiderable sum in the 1870`s of 50,000 USD then further developed it.

Sir Joseph Swan developed the ideas of American John Wellington Starr who had all the ideas in the 1840`s but died, penniless in UK buried in Bimingham, before mananging to develop them.

Sir Joseph demonstrated a practical, longer than few minutes life span, lamp a year before Edison, to the Newcastle Chemical Society.

Cragside in Northumberland, home of Lord Armstrong of hydraulics and arms manufacturing fame, was the first private home in the world to be lit by incandescent electric light.

Adam

[Adam Aglionby]

[Huge]

Now owned by the NT and well worth a visit;

[Bob Mannix]

Also has a hydraulic ram pump (working) and the remains of the generating station (coddled from other bits) and original cabling up through grounds (as well as being a pretty fine house). Notably, on one of the rocks along the stream there is inscribed "Decus et Tutamen", the same as on £1 coins. I haven't made a connection yet.