Energy Efficient Light Bulbs — A Down-to-Earth Means Of Saving Money.
Whenever people ask where they should start if they want to decrease their monthly power costs, the most common response they are going to hear is — change your lighting to energy efficient bulbs. The question of how much you might save can be answered very quickly, using a simple calculation that gives you a figure in dollars and cents.
An example will show you exactly how to utilize this calculation for your own home.
(Note: Kwh means Kilowatt hours.)
Watts times hours per day = watts per day.
Watts/day divided by 1000 = Kwh/day.
Kwh used each day x 30 = total Kwh used each month.
Kwh used each month x $ per Kwh = your total cost each month.
Applying ths calculation we can quickly figure out the cost of running a 100 watt incandescent or halogen light bulb. If you’re lighting a working space, like a sewing room or basement workroom, you might have that bulb on for a daily average of 10 hours. (No, that’s not an exaggeration. I think you’ll see that some bulbs are on a lot more than 10 hours each day, especially in rooms that don’t get much daylight.). In this example we will suppose that you’re paying $.12 per Kwh for your electricity, but you could be paying more than that in your area. You can find your own rate quite easily by checking your monthly power bill.
100 watts x 10 hours = 1000 watts.
Divide 1000 watts by 1000 = total of 1 Kwh each day.
1 Kwh daily x 30 days per month = total 30 Kwh per month.
30 Kwh x $.12 = $3.60 per month. There you have the actual cost of burning a single 100 watt light bulb for the month.
This simple calculation will also reveal to us what the real cost of running a compact fluorescent bulb would be, and how much you would save each month. Switching to a compact fluorescent from a 100 watt incandescent would generally require a 23 watt bulb, but you might prefer a somewhat brighter bulb, like 25 or 27 watts, if you’re used to halogen lights.
23 watts x 10 hours = 230 watts.
230 watts per day divided by 1000 = .23 Kwh each day.
.23 Kwh times 30 days = 6.9 Kwh.
6.9 Kwh/month x $.12/Kwh = $0.83/month. That’s a saving of $2.77 (or 77%) in one month for one bulb.
Swapping 10 halogen or incandescent 100 watt bulbs for compact fluorescents would put $27.70 back in your wallet every month.
This formula can be employed to determine the total amount you would save by changing all your bulbs for compact fluorescents, using wattages that would provide the same illumination as your halogen or incandescent bulbs. Energy efficient compact fluorescent bulbs are available in an increasingly large range of sizes and styles, including bulbs with various bases, so it won’t be difficult to change over. If you have fixtures on dimmer switches there’s no problem; you can find energy efficient bulbs that are compatible, and also heavy duty bulbs that can go into exterior fixtures.
It is true that these bulbs are more costly to begin with. The added cost will not swallow up your savings, though; apart from the decreased power costs, compact fluorescent bulbs will usually have a much greater lifespan than halogen or incandescent bulbs. If the initial cost is a difficulty, just plan to replace two or three bulbs each month and you can spread out the cost over time; the reduction in your electrical cost will pay for the bulbs over the course of the first couple of months.
KEEP your receipts, because the compact fluorescent bulbs usually have a worthwhile warranty. To make sure you can claim a replacement bulb on the guarantee if necessary, put a note on the packaging or the receipt to show which bulbs were put into each fixture.
Changing over to more efficient lighting is a good way to start reducing your energy bills, and you can find many ideas on saving energy at the Energy Resources Journal.
