Your home water heater may soon double as a battery - electrical energy storage systems

New research shows that in the future, one of the lowest, most boring and most common products of home appliances --
Electric water heater-
It is possible to perform a series of new features that will help the grid and even save household electricity.
The idea is that in the future these water heaters will increasingly become "grid interactions" to communicate with local utilities or other coordinating entities, thus providing services to larger grids by regulating their energy use or heating water at different times of the day.
These services may be valuable enough and may even be compensated by utility companies or other third parties. party entities.
"The electric water heater is basically pre-
Installed hot batteries are idle in more than 50 million homes in the United StatesS.
"," Brattle Group, a power consulting company composed of the National Rural Electricity Cooperation Association, the Natural Resources Conservation Commission and the peak load management alliance, published a new report on this topic.
The report found that, the net savings for the entire power system may be $200 per heater per year-some of which may be passed on to its owners-enabling these tanks to work with the grid and engage in some unusual, but there is almost no unprecedented feat.
An example is "energy storage", which includes heating water at night at lower power costs, thus reducing demand for the grid during peak times of the day.
Of course, what the water heater can do in its interaction with the grid depends on its size or water capacity, the country you live in, or the electricity market, etc. the technology is equipped with heaters, and so on.
"Customers with electric water heaters, those already installed existing water heaters can be used to provide this service," said Ryan Hledik, lead author of the report . ".
"You need some additional technology to connect it to the grid, but you don't need to install a new water heater.
Of course, Hledik says that in most cases people may not add technology to existing heaters, but in so-
When they replace the old water, it is called "power-enabled" or "smart ".
In the future, their power companies may encourage or even help them to do so.
Standard electric water heaters-
Set to, say, 120 degrees-
Will heat the water
Depending on the time of use, it's boring all day.
When using some water (
For example, when taking a bath)
, It flows out of the water tank, more cold water flows in, then heated and maintained at the desired temperature.
In contrast, water is heated regularly
For example, heat everything at night.
It may include having a larger tank to make sure the hot water doesn't run out, or heating the water to a fairly high temperature, and then mixing it with the cooler water when it comes out to adjust the extra heat.
With this change, the water heaters will be able to work like "batteries" because they will store thermal energy for a longer period of time.
It is then impossible to send this energy back to the grid as electrical energy, or to use it to power other household equipment --
Therefore, it must be admitted that the battery analogy is limited (
Although the Brattle report titled "Hidden battery" places great emphasis on this).
But potentially huge time.
The lag between the use of electric heating water and the use of water itself will still produce critical batteries-
Like opportunities, especially for grids (
Utilities are now very interested in adding more energy storage capacity).
For example, this means that if water is heated late at night, it can save costs when electricity is often the cheapest.
This also means that the precise amount of electricity the water heater takes out at a given time can fluctuate, even if the heater still does the work.
These services are valuable, especially if many water heaters can be brought together for these services.
This is because the larger grid will see huge demand fluctuations depending on the time of day and the smaller persistent fluctuations.
So if the heaters use most of the electricity at night when most of us sleep, or, if they help the grid "frequency regulation" by instantaneous fluctuations in the use of electricity ", to help balance supply and demand across the grid, then they are playing a role worthy of compensation.
"If the show goes well --
Design, especially meaning, you have
In response to these signals from the power grid, an algorithm was designed to control the water heater, hledik said: "So, what really appeals to the water heating project is, you can run these projects in any different way that the customer will not notice their service. ".
In fact, power cooperatives around the world have been using electric water heaters to provide these services for a long time. member-
Having utilities, in many cases, these utilities control the operation of the member's personal water heater, heat the water at night, and then reduce the electricity bill for all members with saved dollars.
For example, Dajiang Energy, an umbrella cooperative in Minnesota, serves about one person.
There are 7 million people through 28 smaller cooperatives.
The Co-op has been using water heaters for years and its demand director, Gary Connett, said --
Management and membership services.
"The way we operate these large-capacity water heaters, we have 70,000 units that are only charged at night, they are 85 to 120 gallons of water heaters, they come at 11: 00 at night, charges will not be available until 7 in the morning the next day, "Connett explained.
"The rest of the day, the next 16 hours, they won't come.
"As a result, the power used to power the heater is cheaper than the Power charged during the day, so everyone saves money," says Connett.
But this is the first step.
Now, Dahe energy is piloting a project in which water heaters charge at night to help provide grid frequency regulation services by slightly changing the amount of electricity they use.
As the grid adds more and more variable resources, such as wind power, it becomes more useful to use water heaters to provide "Ballasts" to deal with this variability, says Connett.
"I joked that these water heaters are batteries in the basement," says Connett . ".
"They are a little unsung heroes, but we have studied smart appliances and I have to say that maybe the smartest one is the water heater.
"Of course, those of us who live in cities are not part of the rural electricity cooperatives.
We usually buy electricity from utilities.
But utilities also seem to be interested in these possibilities.
The Brattle Group's report states that a pilot project is being carried out in the area by Hawaii Electric Power Corporation and the Sacramento Municipal Utility area.
Therefore, in the future, our power company may try to register for us the project of turning the water heater into a power grid resource (
And compensate us in some way, maybe by buying kickbacks for the grid --
Interactive heater or lower our bill).
Or, or, some people may be in the future with so-
Known as the demand response "aggregator", it brings together many residential customers and their equipment to serve the grid.
It seems that this is not enough, and The Brattle Group report also found that since hot water is a big consumer of the entire electricity --
9% of all household use
These strategies can one day reduce greenhouse gas emissions.
If, at a specific time of day, the heater is used to heat water when a given grid is more dependent on renewable energy or natural gas than coal, that would be especially true.
Controlling when to use a heater may also have this potential benefit.
These are still fairly new ideas, of course, and Brattle Group's report says they need to look into it more broadly.
But as Hledik added, "I haven't met anyone who thinks it's a bad idea yet. ”