Medium to long term thermal energy storage system with embedded heat pumping capability

Introduction

The use of intermittent energy sources such as wind and solar incurs fluctuations in energy production, which lead to gaps in renewable energy availability. Using electricity at peak production to generate thermal energy becomes feasible only if thermal energy storage provides means to decouple generation from production.

Waste Heat in Industrial Processes

Many industrial processes generate large amounts of thermal energy throughout the year as waste heat, which reduces energy efficiency. In some industrial setups, waste thermal energy is rerouted in industrial parks; however, temperature levels, demand schedules, and process proximity rarely play in favor of this circular approach.

Challenges in Sector Coupling

Sector coupling opportunities are reduced due to a mismatch between sector demand schedules. To address these challenges, our main objective is to develop a medium-temperature, medium-to-long-term Thermal Energy Storage System (TESS) with built-in heat-pump capabilities provided by a hybrid approach using TCM & PCM materials.

Objectives and Efficiency Goals

Based on our preliminary analysis, we aim to achieve a round trip efficiency for power-to-storage-to-heat or heat-to-storage-to-heat of 140-160% depending on temperature level, with a storage density of 0.5 GJ/m at lab-scale level, while addressing cost-effectiveness.

Material and Sustainability Goals

At the material level, we aim for a 20% increase in energy density while using sustainable and affordable materials and production methods.

Impact on Decarbonization

By addressing industrial applications, the current project aims at decarbonizing the third most emitting sector in the EU - manufacturing, which is responsible for approximately 20% of the total GHG emissions in the EU.

Future Deployment and Integration

Developing a versatile and energy-dense TESS facilitates deployment within the industrial sector, further enhancing sector coupling capabilities such as:

1. Cascading industry sectors
2. Coupling industrial parks with district heating

This paves the way to flexible and fully integrated energy systems.