19 March 2019
TESSe2b Project - A modular and low cost system of thermal storage technology


Spring 2019

The TESSe2b project is a European project, funded at €4.3 million under the Horizon 2020 programme, which began in October 2015 and lasts 4 years (www.tesse2b.eu). The consortium consists of ten partners, from 8 countries. The project is coordinated by the Polytechnic Institute of Setúbal (IPS, Prof. Luis Coelho).

The main objective of the project is to design, develop and demonstrate a modular and low cost system of thermal storage technology based on solar collectors and efficient heat pumps for heating, cooling and hot water production (DHW), thus contributing to the increase of renewables and provide flexibility for the electricity grid.

Aiming to evaluate the system's integration into building space, a demonstration and on-site monitoring evaluation of TESSe2b solution will be held in three pilot sites (Austria, Cyprus and Spain) to assess its impact in different climate conditions, and provide evidence about its overall technical and economic feasibility.

TESSe2b project developed and tested different solutions to operate with hydrated salts and organic based PCMs, and, in the end, organic base PCMs were chosen. For the TES tanks three paraffins were selected, and they can store thermal energy at three different temperature levels according to the application: A9 for the Cold energy storage tanks, A44 for the Hot energy storage tanks and A53 for the DHW tanks.

For the case of the demosite in Spain they were installed ten solar collectors, one DHW tank, four Hot TES tanks, two Cold TES tanks and the geothermal heat pump with PCM enhanced BHEs (four BHEs, 90 m depth). The layouts of the TESSe2b system are identical for the three demo sites, however each demosite has a customized solution for its specific needs, according with the building energy needs, climate conditions and soil characteristics.

Another TESSe2b project innovation is the development of a borehole heat exchanger (BHE) that can also be used for the storage of thermal energy, thus supporting the system to increase the geothermal heat pump performance in heating or cooling mode. The selection of PCMs for integration into the BHEs was made so as to take full advantage of the ground temperature. It was selected for Austria and Spain, a PCM with a freezing/melting point of three degrees Celsius lower than the ground temperature in order to stabilize the borehole temperature during the heating season. On the other hand, for the Cyprus demosite it was selected a PCM with a freezing/melting point three Celsius degrees above the ground temperature to stabilize the borehole temperature during the cooling season.

Another major TESSe2b innovation is the use of a self-learning management system that will use an algorithm combining a prototype model, a user profile database, weather forecasting and multi-variable controls. This makes it possible for the system operation to be adapted to the building user schedule and, with weather forecasting, to take maximum advantage of available energy that is or is going to be stored, while taking advantage of lower energy tariffs during night time. The control system will be managed according to the input of an array of sensors and actuators that will automatically change the system mode of operation according to the needs of the building.

During the current phase of the project, the TESSe2b solution is being validated and demonstrated in the three demosites and the results can be followed on the project website (www.tesse2b.eu).

After the conclusion of the project the consortium intends to find industrial companies that want to work in partnership towards implementing the solution in the market.

Contact details:
Project Coordinator: Luis Coelho
Email: luis.coelho@estsetubal.ips.pt
Phone:+351 265 790 000

TESSe2b project has received funding from the European Union's Horizon 2020 Research and Innovation Programme, under the Grant Agreement number 680555. This article reflects only the author’s view and the Commission is not responsible for any use that may be made of the information it contains.