Novel advanced hydraulic CO2 refrigeration system for multiple sectors

Introduction

The cooling production, coupled with renewable electricity generation, is considered a cornerstone technology to meet increasing global cooling demand while decarbonizing various sectors. According to the International Energy Agency, the air-conditioning sector alone consumes about 20% of the overall electricity used globally and is expected to double by 2050.

Importance of Efficiency

Improving the efficiency, reliability, affordability, and environmental performance of cooling systems is critical to maximizing benefits for society and the environment.

HydroCool Project Overview

The HydroCool project will develop a novel cooling production concept that can significantly improve cooling system performance beyond the state-of-the-art.

Technical Approach

The solution is based on the hydraulic compression and expansion of CO2 in a reversible cycle capable of delivering cooling for a wide range of applications such as:

• Food preservation
• Data centers
• Air conditioning (operating range: -40ºC to +12ºC)

By switching from solid to fluid dynamics, HydroCool will enable both isothermal compression using liquid piston fluid and energy recovery between the expander and compressor. Preliminary studies indicate a potential to nearly double the Coefficient of Performance through these two mechanisms.

Benefits of Hydraulic Compression

The hydraulic compression is also expected to lead to significant improvements in:

1. System lifespan
2. Operating cost
3. Reliability

This is due to reduced friction and limited use of lubricants.

Environmental Impact

Additionally, HydroCool offers an opportunity to accelerate the transition towards CO2, displacing the use of environmentally harmful HFC and CFC refrigerants with high Global Warming Impact. Combined with the high system performance, this improvement considerably reduces the cooling sector's footprint by almost halving its impact.

Conclusion

Thus, HydroCool will enhance the affordability, performance, sustainability, and scalability of the CO2-based refrigeration system. In the project, a hydraulic CO2 cooling system will be engineered, implemented, and tested at a 17.6 kW scale to achieve TRL4.