We reduced our bill by 4.6% in hot water usage with no quality of life changes


I have an all-electric condo which we rent with Airbnb, it is equipped with a Stream Labs water use monitor. We made two changes that saved hot water with no complaints from the guests. I installed a different flow restrictor in the shower, down from 2.5 GPM to 1.5 and a 1.75 GPM one on the hot water line to the washing machine.

The washer defaults to warm water in the regular cycle. By adding the restrictor I changed the ratio of hot/cold while still leaving the hot water option intact. Guests use the washer a surprising amount. I presume they don’t spend much time selecting the water temperature.

The average shower, per multiple web sources, is 8 minutes. For a couple this is a monthly savings of 480 gallons of water a month. At 1.5 GPM the shower is still refreshing. I used the existing showerhead with a new restrictor. This has the added benefit of keeping me in the lower pricing tier for water.

Humans shower at a predicable temperature (105 degrees) to get the hot/cold ratio you need the average inlet (cold water) temperature. You can find the average on the web or simply measure it. Once you have that it is easy to calculate the hot water saved. Here are my cost to heat water calculations

It takes .000293 Kwh to raise 1 pound of water 1° F
A gallon of water weighs 8.34 lbs.
Average temp tap water in my area is 72 degrees
Water heater set at 120 degrees for us that is 48 degrees of rise
Efficiency of heater .95 (95%) For 2015 and later models .90 pre 2015
Ave price of electricity .105 KwH
Formula: .000293 X 8.34 X 48 X .90 X .105 + .110841 cents per gallon or .1055628 KwH per gallon or 9.473034 gallons per KwH


While you might be saving energy and water, people notice. The question becomes did you piss them off enough that it matters? I notice the water pressure and temperature when I take a shower in a hotel, but I typically don’t complain - just don’t go back. I like to save money, but quality of life and how that impacts you must be taken into account. I don’t mind keeping the heat set lower and wearing a sweater, but don’t mess with my shower. The first thing I do when I buy a shower head is rip the stupid water restrictors out. I want to feel like I am in a waterfall and I don’t care if it costs more. Everyone is different.


I’m with you @32259fl
I have hot water recirculation loop and keep the water heater at 135. I know it costs me a few dollars extra a month that I could be saving. It’s worth the trade off. And now that I’ve turned the pressure up to 105 psi everyone likes it.


These are interesting perspectives to find on a user group orientated towards energy conservation.

In the near future you will see more water conservation when 12% of the entire United States comes under permeant water restrictions in 2020 with further restrictions trough 2030. See: https://www.mercurynews.com/2018/05/31/california-drought-jerry-brown-sets-permanent-water-conservation-rules-with-new-laws/

To answer 32259fl, who stated that I might have a lower satisfaction rate from the guests, I have not seen lower renewal rates. To the contrary, I have occupancy rates in the high 70% low 80% range. This in an area where the norm is below 45%. If Mr. Maslow had established a hierarchy of need for a vacation rental water pressure or volume would be quite low on that hierarchy. Guests want comfortable furnishings, cleanliness, well-appointed property and a great location.


@brownwoodrental, I didn’t read anything that mentioned nationwide reductions. Did I miss it or do you have another link?
Where I live things are much different. Instead of increasing rates for using more water, the price drops drastically. I use about 4,000 gallons a month and pay $6.75 per 1,000. If we were to use 50,000 gallons, the price is $4.19.
It steps up/down in increments with blocks of 5,000 gallons.


As I said 12% of the entire United States. California is 12% of the entire United States as measured by population

Here is the link from the state water board https://www.waterboards.ca.gov/publications_forms/publications/factsheets/docs/water_efficiency_bill_factsheet.pdf
More articles: https://www.washingtontimes.com/news/2018/jun/6/californias-new-water-restrictions-send-residents-/

A trade website: https://www.wateronline.com/doc/permanent-water-restrictions-approved-in-california-0001

Here is a site affiliated with USA Today https://www.vcstar.com/story/news/2018/05/31/permanent-california-water-restrictions-approved-gov-jerry-brown/662456002/

The Sacramento Bee: https://sacramento.cbslocal.com/2018/06/08/new-california-water-law-restrictions-shower-laundry/

and finally here is a site to verify the population of California; https://www.census.gov/quickfacts/fact/table/ca/PST045217


It would have been easier for me to identify if you had mentioned California in the original post. When you state “12% of the entire United States” it makes it sound inclusive of the nation when in reality it’s 1/50 of states.
Would be similar to me saying that 28% of the entire nation can now carry a firearm concealed without any permit. (The only good thing our governor has done)
It doesn’t say it’s limited to any certain area(s).



Be thankful you aren’t in my CA city.
Here are our rates. Summertime watering can be a killer.


They just changed our rates a little last month. Just went and looked. It looks like if using the same amount of water, the bills would be comparable. We use from 3800-4500 a month for a family of four.
We do not have sewer service here at the house but do at the store in town where they basically double the water bill to cover sewage.
Notice how are rates go down with use.


When I last did an analysis about 80% on the total savings of water restrictors came from not heating the water vice reduced sewer and water costs.

We have a separate meter for the drinking water and the reclaimed irrigation water. Punitive rates for the drinking water hit at 3,000 gallons, they double. Before I installed the water saving measures guests would routinely exceed 3,000 gallons for a couple, now they never do. ‘Vacation waste’ is a real cost for any sort of rental where utilities are inclusive.

For the reclaimed irrigation water I installed a Rachio brand smart irrigation controller. I can’t really say if there is a cost savings with it, I can attest that I have a better lawn than the full time neighbors.

As mentioned earlier the hard thing is to save w/o “pissing off” anyone. For this I used the toughest evaluator for my flow restrictors, my wife. I did this in secret. First I added a 2 gpm restrictor which she didn’t notice. A few months later I replaced it with a 1.75 - ditto, again at 1.5. It does not adjust flow for pressure, the actual flow is 1.7, per the water monitor. In between trials we returned to our primary home with a 2.5 gpm that all shower heads have, I believe this is a Federal requirement. She would certainly notice if I had installed a .9 gpm showerhead like they use in hotels.

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I’ve read this thread and your progress, you ha e done an excellent job for sure.
I have had to do the opposite and remove flow restrictions everywhere. Our flow rate is lower do to rural location and having a water softener. I make up for it by having our pressure turned up to just below 120 psi. In the morning and evening it drops to 100 probably due to others on our road using water.
The water use means much less to me than electricity. Heating water is a huge consumer. Having hot water recirculation is added cost to that for me but amounts to $5 or so a month. There are some comforts we aren’t willing to part with.


We move to RI 5 years ago next week. As an engineer, I try to be energy efficient. Since our home had gone through a major renovation in 2009, and had learned that the previous owner had to change contractors during renovation, we contacted National Grid for an energy survey. WE were familiar with what to expect since we did the same thing in our previous home in NJ. Rise came in, did an excellent job, provide us a quote to do the necessary upgrades, of which National Grid paid for 75%. Virtually all our light bulbs were upgraded to LED bulbs, the attic fitted with deflectors to aid air circulation at the eves, a boot around the retractable stairway, sealing of any obvious air gaps and other recommendations for saving energy. Next we got rid of 4 window air conditioners totaling 2 tons of AC and installed a ductless HVAC system equal to 3.5 tons. The first 3 years in RI we used the window units and the last 2 have been with the ductless system. We have also upgraded the kitchen appliances which were only 4-6 years years old, but not as efficient as our current appliances…and a new washer and electric dryer. To make a long story short, we have reduced our electric usage by nearly 11% over the past 2 years. Sense also helps us monitor our usage so that we can minimize spikes especially during peak periods.


This, students, is why you have to be careful reading statistics. Lol.

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