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How I Cut My Electricity Bill In Half

  1. Jul 9, 2009 #1


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    I was able to get my electricity bill down to about half of what it was at this same time last year. It was not any one change I made, but all of these things together that made the difference. As a note, I live in Texas where heat is the issue. Warming the house in the winter is no big expense at all; it is trying to keep it cool in the summer that is the challenge.

    I replaced my 47 year old single-pane aluminum frame windows with Pella Imperiva fiberglass dual-pane windows with low-e coating. I did every window in the house and the sliding back patio door for about $7900. It was not cheap but it made a huge difference. The payback will take many years though. Another benefit was the reduction in outside noise. I also recommend the low-e coating; it blocks about 98% of the heat from sunlight entering the house (no more warm spots for the cats to nap on though).

    I replaced every light bulb in the house with screw-in fluorescent (except the oven and refrigerator/freezer). They use less electricity and they make much less heat (the enemy in Texas). The color is also much nicer in my opinion (day light, not the warm white bulbs). This cost about $200 total, maybe a little less.

    I added about 14 inches of cellulose blown-in insulation on top of the 2 inches of Rockwool and 6 inches of pink fiberglass that was already there. I also added 1 inch thick aluminized foam board panels to the rafters to direct most of the heat towards the ridge vent.

    I sealed up several small leaks in the various A/C heating ducts that were running through the attic. I also added aluminized fiberglass insulation wrap to the ducts in a few spots (that did not get covered by the blown-in cellulose).

    I replaced the mechanical mercury type thermostat with a 7-day programmable unit. I programmed it to have the house cool when we are at home but raise the temp while we are away. I use 78 degrees while home, 81 while away (This is the summer setting. I have not programmed for winter yet).

    I replaced my ~17 year old refrigerator with an Energy Star unit. It seems to be much more efficient than the old unit.

    I added ceiling fans to almost every room. I bought 5 fans for about $600.

    I wrapped the hot-water heater in aluminized fiberglass insulation. It only cost about $21.

    I shopped around for a better electrical rate. I was able to go from about 13.0 cents per kwh to 10.7. This is not an efficiency item, but still reduced my bill. It just took a few minutes on the internet and a quick phone call.

    I would love to install a grid-tied solar panel system on my roof. I have a huge South-facing roof section that would be perfect for this. The panels are still just too expensive though.

    Please share any other energy saving ideas you may have. I am not really a “greenie” but I love saving money when I can.
  2. jcsd
  3. Jul 9, 2009 #2
    1) How many watts do you use in a typical month before and after your modifications?

    2) I think adding ceiling fans will increase your energy bill, although the perceived additional coolness may make you more comfortable with the AC set at a higher level, which could have a net effect of saving energy just because AC uses so much..
  4. Jul 9, 2009 #3
    Do you know how much money you saved by switching to the programmed AC schedule? At my high school the math teacher would get angry because we would only have the AC on while classes were in session, and turn it off when no one was there. She seemed to think that keeping the school at the same 75ish degree temperature was more cost effective than letting the temperature rise at night to make the AC work longer to get the temperature back down to 75ish when school started the next day. Think there's any truth to this?

    As for the solar panels, they might be a feasible solution to our energy needs in the future, but from what I've heard they just cost to damn much per watt to be that useful right now (especially when new and cheaper stuff is coming down the pipe all the time).
  5. Jul 9, 2009 #4
    No. How hot could the room possibly get? At night no less.
  6. Jul 9, 2009 #5
    Are you talking about the school room? If so, it can get up to 105 degrees in there (Arizona).
  7. Jul 9, 2009 #6


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    If it can get that hot overnight, imagine how much more energy it would take to constantly try to keep that cooled. It's probably pretty miserable being in there first thing in the morning, though.

    Though, I've been working on getting RID of the horrid fluorescent energy-saver bulbs the previous owners had in every fixture of the house. I can finally see again. I don't know how anyone can stand those (and of course, they even had them installed in all the ceiling fan fixtures, where they burn out quickly anyway because they aren't vibration resistant :rolleyes:). The only place I'm leaving one is in the entryway light. I don't need that one for much light, just to see my way inside the house as I first enter at night, and to light the stairs. Lights are the one thing I won't compromise on for the sake of energy savings. But, I also have good habits about turning off the lights when I'm not in a room, and when I'm home during the day, I often don't have any lights on anyway, because I can get enough sunlight in the windows (that was one of the important things to me as I looked at houses...they had to be bright with just the light from windows, because I prefer just plain sunlight over any kind of lightbulbs).

    We've had a very cool summer, so I don't yet know how things like the A/C keep up in this house. But, yes, among the first things I did when I moved in was install a programmable thermostat. The ceiling fans are wonderful here, because I don't even need to turn on the A/C with them running. I just have to keep the blinds closed on the side of the house that gets the hot afternoon sun.
  8. Jul 9, 2009 #7
    Why don't you like the fluorescent bulbs? I don't have any in my house, but I've heard it colors the room an annoying blue.
  9. Jul 9, 2009 #8


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    I will have to view the older bills to gather exact kw energy usage numbers for before and after.

    The ceiling fans actually do help keep the comfort level while having the temperature set a bit higher. Of course fans only add heat to a room, no direct cooling. However, fans do directly cool your skin if you are sweating since evaporation removes heat. Since the A/C does significantly remove humidity it makes the fan effect even better.

    As for the programmable thermostat and setting it to various temps vs a constant temp:
    I think that setting it to a higher temp during the day while we are away, and setting it to a colder temp while we are home at night increases efficiency overall. At night the A/C itself is much more efficient since the outdoor temperature is lower. The air temp coming out of the A/C duct during the hottest part of the day is about 56 degrees. The air coming out of the ducts at night is about 50 degrees (Of course that also has to do with how much heat there is in the attic). Plus there is less electrical demand on the grid at night, so keeping my A/C off during the day helps out everyone.

    As for the fluorescent bulbs: the color is one of the main selling points to me. I just love that ultra-white color (called Daylight on the package). They also come in warm-white but it is yucky to me...
  10. Jul 9, 2009 #9
    My housemate bought a 10-pack of compact flourescent light bulbs. They are 60W replacement bulbs that draw 13 Watts. On the box it says, "save $564 in energy costs per package! (as compared to using a 60 watt bulb at 12c / kWh)"

    Who doesn't want to save $564? But how long does it take for this savings to come in, I wondered...

    (60 W)*10/1000*0.12 h - (13 W)*10/1000*0.12 h = 564
    h = 10,000 hrs = 1.14 years

    So it will take 1.14 years to but that's assuming you would leave all 10 bulbs on day and night. More realistically, you would probably have something like 3 bulbs on for 6 hours a day. At this rate, it would take 15 years to save $564. Hah...
  11. Jul 9, 2009 #10


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    So you save about 47 watts per bulb directly, plus that is 47 watts less heat the A/C has to remove from the air. Double benefit in my book.
  12. Jul 9, 2009 #11


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    I switched all my bulbs from 60W and 100W to 9W and 13W. I don't notice much of a difference.

    You get better quality ones and it's nice and white.
  13. Jul 9, 2009 #12


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    It's not just about the money. Jeez... when are people going to learn.

    Also, good point IMP. Lights warm up the house quite a bit.
  14. Jul 9, 2009 #13


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    If it weren't all about the money, every homeowner would be lining their roofs with solar panels :rofl:

    The thing I love the most about CF's is.... You don't have to replace them so often!!! They're great for those annoying to replace lighting fixtures in your house like ceiling fans. Pop one in and you're probably set for a few years. I honestly don't even remember when I last replaced the bulb in my computer room's ceiling fan.
  15. Jul 9, 2009 #14


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    No, they weren't blue. They just seemed very dim. And, at least some of them (I'm not sure they were all the same type in different fixtures) were like fluorescent tubes that seem to take some time to warm up before they got to their full brightness. They were very uncomfortable for reading...that's about the best I can describe. I was getting ready to replace the fixture in one room, thinking it just wasn't enough light for the room and that I needed one with more bulbs in it, until I realized it had those CF bulbs in it, and tried just changing to regular incandescent bulbs...it made a HUGE difference.

    Using 60W incandescent bulbs (clear, not frosted), I can leave just two lights out of 4 on a ceiling fan fixture on and be comfortable with the amount of light I have. With the CF bulbs in that fixture, I had all 4 lights on, and it still felt dim.
  16. Jul 9, 2009 #15
    One thing I don't like about the compact fluorescent bulbs is their sensitivity to power and temperature fluctuations. Back when I used to run an automotive shop, I thought it would be a great idea to replace all the standard bulbs with energy efficient ones. Ended up buying 40 or so of them. Whenever colder weather would set in, I'd be constantly buying new ones. Seems they would only last a few weeks at most.

    The power fluctuation problems were probably more my fault than anything else. I guess turning on eight 230v vacuum motors at the same time had something to do with it.:uhh:
  17. Jul 9, 2009 #16
    The biggest annoyance is that you can't put them in lights which are on a dimmer.
  18. Jul 9, 2009 #17
    Have you checked out any rebates or tax credits on the cost of installing solar panels? You may even be able to sell extra power back to the power company. If you haven't then it is worth looking into.
  19. Jul 9, 2009 #18


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    Compact fluorescent bulbs have good points and bad.
    They do seem to last longer to me.
    They can make noise in very quiet environments, seems to be more noticeable in cold temps.
    The color is a huge plus to me (the daylight ones).
    They use much less electricity.
    They make much less heat.
    Modern ones turn on instantly, no warm up time like the older ones from years ago.
    They are getting less expensive by the day it seems.
    They don't burn you if you touch the bulb, great in work lights etc.
    Won't work with traditional dimmers.

    Can't wait to see what becomes of LED technology. Every flashlight I have is LED and I will never go back to incandescent. HID might have a place too, time will tell.
    Last edited: Jul 9, 2009
  20. Jul 9, 2009 #19


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    Thanks for the link! I will definitely check it out. I know there are tax credits. There are also property tax exemptions (they won't raise the value of your house by $15,000 even if you just installed $15,000 worth of solar panels). I know there are buy-back programs in my area, offered by at least two local utilities. I need to look into this more, maybe the price shouldn't turn me off as much as it does. Thanks again!
  21. Jul 9, 2009 #20
    CF lights also produce less light when the air is cold.

    CF lights can be manufactured to have specific color (eg cool blue, warm).

    CF lights have low power factor, which causes them to draw large amounts of reactive power which is not measured by your power meter, but still costs the power company.
  22. Jul 9, 2009 #21
    Hopefully you can dig up something to help make it affordable enough to be worthwhile. If you have any questions about installation or effectiveness of photovoltaics then I'm sure there are many people on this site that would be thrilled to answer. It may help you make whatever decision is best for you.
  23. Jul 10, 2009 #22


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    I think it is a matter of experimenting and selecting the best combination. I have replaced almost all bulbs in the ceiling lamps with CF bulbs and it works, but where I work and/or read I have additional lamps to keep the place brighter.

    But in my experience you have to ignore whatever they wrote on the box - if they advertize the CF bulb as being replacement for incadescent 60W, use it as a replacement for incadescent 40W, and so on.

    And I have left incadescents in kitchen and toilet, these are places where I don't want to wait till the bulb gets hot & bright, I need light NOW :smile:
  24. Jul 10, 2009 #23


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    Cavity wall insulation? Made my house a lot warmer instantly.
  25. Jul 11, 2009 #24


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    I've been replacing all of the crummy fluorescent low light bulbs in the light fixtures in my place. I thought I was going blind. I also removed all of the milk white light bulb covers so more light is available. For some reason they had those in all of the closets and you couldn't see a thing.
    Last edited: Jul 11, 2009
  26. Jul 11, 2009 #25
    I'm assuming you mean CFL's? Are you aware of the safety precautions that you need to take? If not I recommend that you read this, just in case, especially for breakage/clean up.


    I apologize if you've already read about this.. but better safe than sorry! :)
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