On Friday, December 13, 2013 11:23:19 AM UTC+13, Cursitor Doom wrote:
There's a new system coming out for early detection of failing lamps for
seamless replacement by use of the 'distress signals' they emit in the RF
spectrum shortly before failure. These signals are visible on handheld
spectrum analyers which can be driven around in vans checking the
'health' of such lamps; the antennas enable the distress signals to be
detected from further away, thereby shortening the route taken.

Here in NZ we need a lot of light houses, some on small offshore islands. Even when they became automated, they still needed their lights changed and fuel supplies.
So an ingenious person designed solar powered lighthouses, and that have five lights on a rotating mechanism. When a light fails, it automatically changes to a new bulb. So every few years somebody puts some new bulbs in place. But there's no urgency to do that.
Why don't they have street lights that change their own bulbs? OK, someone will steal them.