Alas, I don’t have TOU (Time-of-use) pricing. I still have cheap power but not TOU pricing. You may have it so if you do and have an electric water heater this tip may help save you some money.

I will use Duke energy from another state as an example. North Carolina sounds good. So I look at the rate schedules and I actually find a specific one just for water heater. I am going to post the TOU verbiage.

This service is solely for the purpose of water heating and will be provided from the Company’s 60 Hertz, single-phase residential service. This service will be controlled by the Company using a load control device, and submetered in the Customer’s water heater circuit. The Company shall have the right to interrupt service to the Customer’s water heater under this Schedule. All water heating controlled under this Schedule shall be served through a single submeter. The submetered service will be available at least six hours out of twenty-four hours.

What does this mean to us normal people? Well, most likely the six hours is going to be in the middle of the night. You are going to have to heat the entire days water at night. This could be a problem but all you need to do is turn the water heat up. Not a natural thing but there is a device that will help you not to burn yourself. It is called a tempering valve. Some call it a mixing valve because it mixes the very hot water from the tank with some incoming cold water. Usually they are set at 120 degrees but you can change the setting. The job of the tempering valve is to maintain the set temperature at its output regardless of the incoming hot or cold water temperature. So, if you wanted to, you could set the tank for 160 degrees. This would burn you instantly if not for the tempering valve.  50 gallons of 160 degree hot water mixed with 50 gallons of 60 degree cold water give you 100 gallons of 110 degree water. (shower water temperature) Now I have an 80 gallon tank so I could have 160 gallon of 110 degree water. That is a lot of hot water. And just so you know, the rate for this service is 4.23 cents per kW hour. The normal rate is 8.60 cents per kW hour. This amounts to a saving of over 50%. Since the little yellow tag says the water heater use over 4500 kW hour a year the total saving is about $200. Since a tempering valve costs just north of $100, you could see payback in under a year. This is a submetered utility controlled deal. That means you don’t have to do a whole lot. I am not for sure but it sounds like they come out and hook it up. Done.

For the remainder on the population, you are going to have to buy a water heater timer. Like this one. It sells for no more than $70. The nice thing is that it is just like a programmable thermostat.

The time switches can be programmed for repeat daily scheduling, 5-day working week scheduling, weekend scheduling or any individual day scheduling. Timers can be scheduled for operation during the lowest time-of-day rates or to switch off the electric heater during period of utilities peak power usage. The time switch can be set to operate for up to 6 ON/OFF operations daily for a maximum of 42 on/off operations weekly.

Here is a good site all about water heater timers. You could cut your water heating by as much as 50%. Me, I think 25% maybe more realistic. Add that to TOU electric rates and then you could easily get over 50%. It is very easy to install and will pay for itself in less than a year. But, since I don’t have TOU billing, I will have to let someone else save money.