Desiccant Cooling Analysis : Simulation software, energy, cost and environmentalanalysis of desiccant cooling system

Abstract:

Desiccant cooling is a technology that, based on a open psychrometric cycle, is able to provide cooling using heat as the main energy carrier. This technology uses a considerably smaller amount of electricity than refrigerators based on the vapor-compression cycle, which is an electricity driven cycle. Electricity is often more expensive than other types of energy and has CO₂ emissions associated with its generation , so desiccant cooling has the potential of achieving both economic and environmental benefits.

In addition to this, the heat the desiccant cooling cycle needs to work can be supplied at relative low temperatures, so it can use heat coming from the district heating grid, from a solar collector or even waste heat coming from industries.

The system which will be studied in this report is a desiccant cooling system based on the model designed by the company Munters AB. The systems relies on several components: a desiccant rotor, a rotary heat exchanger two evaporative humidifiers and two heating coils. It is a flexible system that is able to provide cooling in summer and heat during winter.

This study performs a deep economic and environmental analysis of the desiccant cooling systems, comparing it with traditional vapor compression based systems:

In order to achieve this objective a user-friendly software was created, called the DCSS – Desiccant Cooling Simulation Software – that simulates the operation of the system during a year and performs automatically all the necessary calculations.

This study demonstrates that economic savings up to 54% percent can be achieved in the running costs of desiccant cooling systems when compared to traditional compressor cooling systems, and  reductions up to39% in the CO₂ emissions. It also demonstrates that desiccant cooling is more appropriate in dry climate zones with low latent heat generation gains.

In addition to that, the DSCC software created will help further studies about the physical, economic and environmental feasibility of installing desiccant cooling systems in different locations.