A student of FIT came up with a smart water heater which can reduce costs by up to a third

Turning a standard water heater into a smart one using an affordable device and reducing consumption by up to a third. That is what Adam Grünwald of the Faculty of Information Technology of BUT managed to do in his Bachelor's thesis. Furthermore, his invention can connect to the Google Calendar which for example allows the water heater to know when its owner is leaving for a vacation. Grünwald plans to further improve the device and even considers placing it on the market.

A standard water heater heats water continuously throughout the day and maintains a steady temperature regardless of whether anyone is taking a bath at the moment or not. "That means that higher water temperature is maintained both during the day and in night, even if nobody takes a bath at those times. That naturally leads to higher temperature loss," said the FIT BUT student, Adam Grünwald. In his Bachelor's thesis, the outcomes of which he also presented during this year's Excel@FIT, he devised a device which turns the water heater on only if needed. "The device can fairly accurately estimate the temperate inside of the water heater and at the outflow pipe and draw a heating plan based on the temperatures from previous days. That means that the programme detects highest temperatures at the outflow pipe and controls heating on their basis. For example, it can learn that the temperature always goes up around 7:00 a.m. and 6:00 p.m. It will then prepare and heat water at these times so that it quickly falls back to the holding temperature after being used," Grünwald described the basic principle of his invention.

However, when devising this solution, Adam Grünwald also thought of non-standard situations. In the second phase, he wants to combine all functions within a single device | Author: Adam Grünwald's archive "A vacation may represent such an anomaly. When the entire household leaves for a week, the water heater would keep heating water based on the data from previous weeks and would not reflect the owners' absence in any way. Or rather it would reflect it with a delay. That means that when the owners would return, the water heater would have no data from previous days and would not heat water," Grünwald explained the issue. He solved the issue by connecting his device to the Google Calendar. "Virtually everybody has this application in their phones. Then you can simply create an event in the calendar covering the period during which you will not be at home. The water heater will then know not to heat water. This period will also not be taken into account in the device's calculations and, after the event ends, the device will continue using data from before," added Grünwald.

The Calendar can be used for more than just for setting vacations. You can also use it to pre-heat water for example when you return home at night and there would normally not be heated water ready for use. "The user can set a specific hour when the water should be ready. For example, if the user goes jogging, they can set that the water has to be heated up in an hour. So as soon as the user finishes their run, they can take a shower with a pre-heated water," explained Grünwald, adding that the device itself will calculate when the water heater should be turned on to be able to heat the water up.

In the second phase, Grünwald wants to combine all functions within a single device | Author: Adam Grünwald's archive

As part of his Bachelor's thesis, Adam Grünwald tested his device in two households and it turned out the average savings were around thirty percent. Even though Adam Grünwald says his idea is not entirely unique, a similar solution is not available on the market. "Of course, there are smart water heaters on the market. But if you already have an older model and would like a smart water heater, a total replacement is unavoidable," said Grünwald, adding that he found a solution that would turn any water heater into a smart one only in the portfolio of a single manufacturer in the USA.

This is one of the reasons why he would like to continue working on his device both during his Master's studies and privately and, one day, offer it to interested parties for purchase. "However, during the first phase, data collection and evaluation ran on a laptop. It would be necessary to get a single device to perform all this functions. It is also necessary to solve tariff customisation. Some people have their water heaters plugged in sockets that only work with low tariff," Adam Grünwald lists some of the challenges as a parting note. Currently, he wants to use the holidays to think about the future of the entire project. But he definitely plans to return to it after the holidays.