Many moons ago, maybe as much as 20 years, a friend took me to see a man who was very much into the latest 'stuff'. He had a 500 watt security light on the side of his house. These are commonplace now, but unheard of then, and he explained this was to enable his CCTV to get visibility for security. I was sceptical at the time that this was absolutely necessary and that it didn't actually advertise that there was something to steal at this property.
Time moves on and we all have outside lights for 'security' or merely for convenience of seeing around the property at night. I noticed recently that these are still sold as 500w (which as you know is half a kilowatt to put it in context). I have been frustrated and annoyed by this and secretly turn the light off but am told off a day or so later for it. Cats, hedgehogs, foxes and other small mammals set these off and at half a kilowatt they are not good for light pollution or for energy expenditure.
We have been looking around and found that there are now 150 watt versions of the bulb available and have changed the light to a much smaller power. I am pleased to find that the light is still thrown as far as I want it (the bottom of the garden for the compost bins) but not so far outside the garden, thus reducing light pollution. It also has the added benefit that I can go to the bins at night and not get a tan!
My father-in-law is now 90 years old and was complaining that his room was too dark at night. It was faddy, particularly in the 70's and 80's, to have light fittings with lots of low wattage bulbs that gave a 'public bar' type of feel to a sitting room. As you get older you do, however, need more light to see and this is where he found himself, needing more light with a light fitting that won't take more wattage. I asked him to have a look and he turned up 5 energy saving bulbs of 20 watts each and and I explained that more light didn't need more power. We changed 1 and he was amazed at the effect. I changed a second and took the remaining ones out and he was delighted with the light. We had taken the power consumption from 125watts to 40 watts yet tripled the amount of light in the room. The problem remains in that he has 3 empty light sockets and 2 ugly bulbs, but now he can explore the options of what to do next knowing that he wants at least 200 watt equivalent of light in the room.