[quote=dougwalkaboutWorse yet, if you're in a hot climate, all the vampire power is radiated as heat. So you're using (and paying for) extra electricity for air conditioning to remove your wasted electricity. Argh!
I still have CRTs, and in the Winter, I don't have to turn the regular heat on.
It seems the underlying ideas are: better able to handle long-term price rises and not being wasteful. I can see if you're paying $80, if the generation prices quadruple, you're paying $320, but if I paid $100, I'll be paying $400, which at that time, $80 might be able to buy something![/quote]
My LCD monitor went out in the fall and I've resisted replacing it because I had a CRT in storage and realized the extra warmth might be good.
Your point about the extra electrical power coming off as heat, heat you suffer from and pay to remove using AC is very good. I went into a restaurant and noticed they used 75w MR-16 lights. Lots of them. I counted forty. Which run any time the place is open. Which is like running a 3000 watt heater, and then running an AC system to keep the building, sitting in the Florida sun, from getting too hot.
The same situation in, I don't know, North Dakota perhaps, would be different. You might need the heat. But down here it is costly and wasteful.
Of course using less power is good but the only way to make sure you are getting the most bang for your buck is to carefully consider the situation. You almost always get the biggest payoff going with CFLs in any fixture that stays on the longest.
To figure out the payoff you need to have some idea of the cost you pay for electricity, the number of hours a day the light stays on, and any factors that might shift the calculation. The average cost of electricity you can get off your power bill. Alternatively here is a nice resource:
http://www.eia.doe.gov/electricity/epm/table5_6_a.htmlHow long you burn the bulb depends on your use. If it stays on all night you can estimate 12 hours a night. Which will be high for summer use and low for winter but should average out about right.
Other factors are like those MR-16s in the restaurant where you pay for the light and then pay again to shift the heat out of the building.
I have porch lights front and back and a light in my bedroom/office, and another in my living room that stay on any time it is dark and/or I'm up. Figure the porch lights stay on 12 hours a day. the two main interiors 6-8 hours a day. Going from 60 and 75w incandescent bulbs to 13w CFLs made sense and I saw a good reduction in my power use in a single month. Payoff took only two months and I've saved ever since then.
Other fixtures have slower payoff and I've been much slower in converting. A good example is my hall light. It runs less than a minute a day on average. Payoff would take years.
There is also the matter of CFLs coming up to full light slowly. Particularly when it is below 40. They get better every year and in a room, say for a reading light, a few seconds coming up to full output isn't an issue. In a hallway it is annoying.
There is also the fact that CFLs, like any fluorescent light, tend to wear out by starting. Incandescent lights wear out during use. Fluorescent tubes last longest if started once and get left on. In the early 70s most department stores left their lights on 24/7 because the shakeout on price was that what they paid in electricity they more than lost in replacement costs.
Left on all the time CFLs will generally outlast the incandescent lamp they replace and save electricity doing it. Use a CFL in a location that gets turned off and on a lot and you don't see the longevity advertised.
Generally changing out incandescent lights for CFLs in fixtures that sty on at least a few hours a day is a no-brainer. Go for it and enjoy the savings. On less used lights it is a longer term proposition.
LEDs get tossed in a lot as the logical step up from CFLs. Maybe. They really aren't much more efficient and they cost five or ten times as much. On the up side LEDs don't suffer from early failure if they get turned off and on and they come up to full power immediately in the coldest temperatures. Making them ideal for specialized situations like hall lighting in an industrial freezer. Most people can make major efficiency gains for shorter money with common CFLs.
LEDs may indeed be the wave of the future but returns on investment are still low and payoffs are very slow. Give them twenty years. When the unit cost goes down to what CFLs cost now they will be the way to go.