First results from the Ecovat in line with thermodynamic analysis.

Slim en Voordelig OnlineEcovat demonstration site, News

Ecovat is a company with a patented breakthrough technology for thermal energy storage over the seasons. Ecovat is at the end of product development and ready for market introduction. To enter the market a test and validation process is made.

Ecovat produces one of very few solutions for energy storage “over the seasons”. And is at this moment by far the most affordable and efficient. The next best solution is pumped hydro, that is less efficient and only economical in mountainous areas. The Ecovat Technology is protected by the various IP rights in EU and USA.

The International Energy Agency IEA recently published Task 45 a report about the state of the art about LARGE SCALE Seasonal Thermal Energy Storage systems. This report gives also insides in the different systems and there performance.


Testing Ecovat’s principles and performance

On our demo site we are able to do tests on the Ecovat Model S(mall). This is the smallest version of the Ecovat energy storage. The storage has a volume of 1500 m3. It is divided in 5 sections and each section can be switched on or off.

For the KIC InnoEnergy assessment, the Universitat Politècnica de Catalunya – Barcelona (UPC) has made a report of the thermal dynamic analysis of the Ecovat. This report gives more insights in Ecovat’s thermodynamics. The report is available on our website.

Thermal Stratification

Thermal Stratification in a Thermal Energy Storage Tanks is an important aspect related to the performance of storage. The thermal stratification is the existence of a temperature gradient (thermocline) in the storage that allows the separation of fluid at different temperatures. See below.

Differing levels of stratification within a storage tank with equivalent stored energy (a) left, highly stratified, (b) center, moderately stratified and (c) right, showing a fully mixed, unstratified storage.

In Figure (a), the temperature gradient between the hot and cold regions of the storage is observed to be large and the thickness of the thermocline small. In Figure (b), the temperature gradient is smaller and the thickness of the thermocline is larger than the storage shown in Fig. (a). In effect, the storage shown in Figure (a) is more stratified than the storage shown in Figure (b). Finally, in Figure (c), the storage is at a uniform temperature and is observed to be un-stratified.


Numerous studies have been conducted to quantify the effects of stratification on the performance of the systems, the thermodynamic benefit of maximizing the temperature and exergy. A stratified storage has the benefit of delivering hot water to the load without auxiliary heater input. Each layer of the Ecovat can be switch on or off. The Ecovat system can be steered to maximize energy quality in function of energy price.


The first data from the Ecovat

With a calibrated temperature gauger, with a precisely in hundredths of degrees, we have measured the temperature at different depths in layer one and in fact you can see that the highest temperature is at the upper side of the layer. Short time heat is added to the layer in order to test the heat equipment.

We are now calibrating all sensors in the Ecovat on basis of the calibrated meter. After that we add heat to layer one and lift the temperature up to 60 degrees Celsius.

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