I've always wanted to know if it is faster to heat water on the stove with a lid on or off and if it is faster, how fast?

I've also wanted to know how much water I waste when I turn on the spigot in the bathroom and wait for the water to heat up. I found out my answers below via unscientific study.

Heating Water for the Shower
I had 3 - 1 gallon containers that I used and hoped it wouldn't be more than that for the water to heat up. A 5 gallon container would have been easier, though heavier, as I did waste water in switching between containers, but feel I got a good estimate in the 3rd container.

Over all it took 2 1/3 gallons before my water heated up enough for me to want to get into the shower. These containers were later set aside for flushing the toilet.

What I learned to conserve:
○ Don't use the faucet to let the water warm up, use the low-flow shower-head to cut down on water waste
○ Get myself acclimated to cold showers by getting in immediately and no waiting needed
○ Taking a bath would allow me use less water and the leftover water can be poured into a bucket to use for flushing the toilet, water lawn and water plants

Boiling Water on the Stove
Lid or no lid, that is the question. Is there a decent time difference in one over the other?

I didn't find much of a difference and I tried to keep the experiment as similar as possible - same pot, same starting temperature and same burner.


Both pans had 1 egg in it and the water was just over the egg. Both pans were heated up on high to bring to a boil and on the same burner. The downside is there was a roast cooking in the oven that I didn't think about.

Overall the pot with the lid did heat up faster than the one without a lid but not by much; a difference of 14 seconds seperate them in coming to a boil when put on high. If I had more in the water, that difference might be greater, but another test would need to be done.

What I learned:
○ Using a lid does allow me to get my eggs boiled faster in the morning
○ Not using a lid would give an indirect affect of heating up the kitchen on a cold morning
○ Most important is what I can do with the water afterword to not waste it

6 Comments

  1. Rzrshrp // Friday, July 31, 2009 10:41:00 AM  

    Wow, 2 and a half gallons for the water to get warm. That is pretty wasteful. I feel guilty about that sometimes but there's no good alternative that I can implement right now. I'm pretty sure that using a low flow showerhead doesn't make a difference in the amount of waste and will take even longer. The water is cold because if the hot water hasn't been used recently, you're waiting for the hot water to move all the way from your water heater to your faucet. It will just move slower with a low flow showerhead. There are only a couple solutions for this that I can think of. 1) Really good hot water pipe insulation so that water stays hot longer in your pipes or a closer water heater. I sometimes fantasize about having a tankless water heater right next to my bathroom. With that, there's less feet of room temperature water that has to be flushed out of the pipes.

    It seems that you did a redesign on your page. It looks nice.

  2. Dawn // Friday, July 31, 2009 11:42:00 AM  

    @Rzrshrp
    "I'm pretty sure that using a low flow showerhead doesn't make a difference in the amount of waste and will take even longer."

    I was wondering about that myself - does water heat up based on the amount of water that flows through the showerhead or just the time it takes from water heater to my bathroom? If it is the latter, then the showerhead would save me water waste. If it is the former than I might as well take baths.

    Like you I would love to get a tankless, good idea for a future house I may buy.

  3. Anonymous // Friday, July 31, 2009 8:00:00 PM  

    I've been trying something different this year. I run the water (both shower and dishes by hand) into a container until the water warms. When enough hot water is in the sink for the dishes, I rinse cold into a container (diluted soap and all). I then hand carry this water to the small gardens in the yard. Extra work, but over 1000 gallons saved a month compared to before the trial, and the vegs are doing great. The effort is really not that much and very satisfying (and I'm not a green freak at all). P.S. Using a low flow shower head makes no diff. There is a set volume of water between the water heater and the faucet regardless of the flow (unless you're talking a small drip, which would have time to cool off).

  4. frugalurban // Saturday, August 01, 2009 1:18:00 PM  

    I have never felt guilty about running the water until it gets hot . . . until now! I don't pay for water, but I do pay for electricity to heat it, so that is money down the drain. What great ideas to re-use the water though.

  5. Dawn // Saturday, August 01, 2009 4:20:00 PM  

    @Anon -
    That is an idea as well!

    @frugalurban
    Guilt hits me in strange ways, this was more of an observation test and trying to decide how best to handle it.
    I could always just turn the spigot on until the containers are filled up and bathe with that - also considered by some a "sink bath".

  6. bugbear // Wednesday, August 26, 2009 11:48:00 PM  

    2 ideas:

    one, to heat water for teamaking and such, and even for boiling eggs, the microwave is much more efficient than the stovetop in terms of energy usage. Acup of water for tea boils in 3 minutes in the average 1000 watt microwave, which amounts to 3/60 or 1/15 of a kilowatt of power usage or 3 cents where I come from (20 cents per kw/hr.

    Second, to save a lot of water flushing the toilet, you can put a half gallon or gallon milk container with a top on it to the side of the toilet and go in that when you only have to urinate. Cap it when you're done so it doesn't smell up the place, and when it's getting pretty full, dump it into the toilet after you've done a number two.

    The average male could save maybe 1 or two flushings a day using this technique, which amounts to serious water.