iHeat: A thermal battery for home heating

The iHeat thermal battery is intended as a sustainable and efficient energy storage system for home heating. Consider the following: when solar energy is available, often the temperature is such that your house does not require heating. On the other hand, when the temperature is low, everyone needs to heat their house, placing high load on the electrical network (and increasing prices). If energy is stored efficiently, then energy from sun during the day can be used to heat your home at night. And, likewise, electrical energy can be used late at night, when demand is low to recharge your thermal battery.

In the iHeat system, energy is stored in salt crystals that absorb heat when they dry out. As the salt hydrates (absorbs water), the crystals release heat, which can be used to heat your house. This is much more efficient compared to storing energy in hot water. As water heats up, it stores energy, but, that energy escapes as the water cools. Thus, the hot water must eb extremely well insulated if it is to retain its energy for very long. The salt crystals never get much warmer than room temperature, making it easy to insulate and retain the energy for long periods of time in the crystals.

The iHeat project aims to build a system that is capable of storing sufficient energy to heat a home and can be used for central heating in a household. To control this, the temperature, and humidity of the salt crystal chamber needs to be accurately measured. In addition, it is important to measure how much energy is stored in the battery.

We are developing the sensor systems to measure how much energy is stored in the battery, and how much heat is being delivered to the home. The sensor data will then be converted into an easy-to-understand form so that the user can control the battery just like they would control a normal central heating system.

This project is a collaboration between TNO, TU/e, Fontys engineering, and Fontys applied physics.