"charles" wrote in message
...


But a 150W halogen lamp would actually suffice for many. Our back garden
is amply lit by one - stays on for maybe a couple of minutes as needed.
Others in the area light similarly sized gardens with 500W left on for
hours/all night.

"but a 150w halogen"? Why not use a 40w sodium? We use two in our
Village
Hall car park.

Because you can't turn the sodium lights off and on quickly so the silly
buggers leave them on all the time causing light pollution and wasting
energy.
A 150W halogen on a PIR or two is much better, it wastes less energy, it is
brighter, it is whiter, and you can see intruders as it goes from dark to
light suddenly.