Anurag Sachan receives Award from Etat de Vaud

© 2013 EPFL/LENI/SACHAN

© 2013 EPFL/LENI/SACHAN

LENI is pleased to have supervised the master work of Anurag Sachan for which he has received the price of État de Vaud. "Study of the Integration of District Heating and Cooling with an Electro-Thermal Energy Storage System" was done under the advisory of Dr. François Maréchal.

Summary

Large scale energy storage is likely to play an important role in the power generation and distribution sector, especially when increasing large shares of unique renewable energies will be integrated into the electrical grid. So far pumped-hydro is the only technology which has been widely deployed for this purpose. However the spread of the pumped-hydro technology is limited due to the geographic constraints and can not be deployed so easily in unfriendly locations. At the same time, pumped-hydro involves a ecological destructions and the new one often requires a higher investment costs associated to the infrastructure and the ecology. Another drawback of the pumped-hydro storage is that they overload the electricity transmission grid while charging since, electricity has to travel back to the site dependent pumped-hydro plant.

In this master project (thesis) work, a specific implementation of the energy storage concept based on the thermodynamic cycles has been analysed thermoeconomically. This concept is originally introduced and developed by Corporate Research, ABB Switzerland Ltd. The concept uses the thermal medium for the energy storage and thus, named as electro-thermal energy storage, ETES system. The ETES concept uses a CO2 based transcritical rankine cycle for the charging and discharging modes while creating its own heat source and heat sink. This concept is a site independent energy storage and scalable up to a giga-watt hour (GWh) range of the stored energy. The fundamental idea in this project is to store electricity in a thermal form and then to deliver electricity, district heating and/or district cooling services to increase the overall profitability and operational flexibility of the energy storage system.