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Computer Log #26 for

Technology today has hit every corner of our lives, and technology can be used to save money as well, and in this tough economy, that is a good idea. Since the time of the invention of the light bulb after many failures by Thomas Edison, it was not a concern that lights and the light bulb would take so much power to light our lives up. Since Edison, and in the last 20 years, we have compact florescent bulbs where a 13 watt bulb gives off as much as a 60 watt incandescent bulb. Now with LED light bulbs coming on the market, I expect to see even lower wattage for the same amount of light.

Why is wattage so important? I will try to give you a lesson in how to figure out the cost. I was never good at math so here goes. Every power company uses the term Kilowatt and Kilowatt Hour or KW and KWH. A Kilowatt equals 1000 watts and Kilowatt Hour equals 1000 watts running for 1 hour of usage. So let’s say if you have 10, 100 watt lights on in your house for 1 hour that will equal 1 Kilowatt Hour or 1 KWH. Now let’s say if your electric cost is 20 cents a KWH. That means your cost to run those 10 light bulbs is 20 cents an hour. Maybe that does not sound like much, but if you keep those bulbs on 10 hrs a day that will add up to $2 dollars a day or $60 dollars a month. Remember I used 20 cents because it is a nice round number for ease of use.

Now replace those 10, 100 watt bulbs with 13 watt compact florescent bulbs, and at the same usage of 10 hours, that will equal 1300 watt hours a day and 30 days will equal 39 KWHs and will equal $7.80! What a savings for a month, and I used the same 20 cents per KWH. That cost would be even better if you did not leave all the lights on.

Now lets talk about that nice new 50 inch flat-screen TV you just purchased. Did you know next to your clothes dryer and electric hot water heater, and electric range, this new TV is a power hog and I have seen a number of them draw 1500 watts in performance mode. Using 10 hrs a day will equal 15 KWH a day times your electric KWH cost of 20 cents which equals $3 dollars a day times 30 days equals $90 dollars a month. Now if you used power saver mode in that new 50 inch TV, it may cut the bill down to $30 dollars a month.

I have 3 yard lights for my driveway and parking area. I only turn them on for several hours a night, but I found that there is a Compact Florescent replacement bulb for the older yard lights and it only draws 75 watts compared to the older 175 watt mercury vapor lights. I also use sodium lights with their golden glow; these lights also use less power. Since these types of lights last for years, in my case, I got 30+ years out of mine by using a switch and not leaving them on all the time, which is a big money saver.

Now as far as your computer goes, most desktops and laptops do not draw that amount of power but expect 90 to 250 watts as the normal, even with the big computers with the large power supplies. You only use power in burst and not all the time. I have seen my towers at my data center only draw 35 watts or so per tower running standard web server software. I will write more about this in a later Computer Log.

Many thanks to Bob Kaylor who taught Electrical Trades at the Fredonia BOCES Center many years ago and who taught me well.

Franklin S Werren is a Computer technician and runs Chautauqua Lake Hosting and Franks Radio in Sherman ` NY. And can be found on the web at , and , also via e-mail at

Disclaimer: Neither “Franklin S. Werren” or the “Chautauqua Star” have received any money or promotional items in anything talked about in this column.

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Page last modified on June 12, 2010, at 04:44 PM EST