Indirect Evaporative Cooling

Ongoing (2020 - 2025)


The project objectives are as follows:

  • Carry out deep and wide investigations of indirect evaporative cooling systems, as well as for cooling towers, including cost, space, maintenance, and environmental impacts (noise, legionella and so on) to find out the main reasons why indirect evaporative cooling technologies have not been widely used.
  • Carry out field testing of existing indirect evaporative cooling systems applied in different climates to obtain real-world running data; analyze the data and provide guidance for system improvement or optimization. (Existing installations can be found in the north-west of China, western USA, Europe, Australia, and other dry regions.) 
  • Develop a general theoretical analysis method for indirect evaporative cooling processes to guide the design of various indirect evaporative cooling systems used in different dry climates.
  • Evaluate the water and electricity use of indirect evaporative cooling processes.
  • Set up a system simulation model and tool for various kinds of indirect evaporative cooling processes and systems used in different types of buildings under different dry climates.
  • Develop a guideline for designing indirect evaporative cooling systems for different types of buildings under various dry climates and water resource conditions.

Four Subtasks are arranged to finish the main tasks as to achieve the objectives of this Annex:

  • 1. Definition & Field study
  • 2. Feasibility study of IEC technologies
  • 3. Fundamental study
  • 4. Simulation tool & Guideline.

The planned official project deliverable is a book, provisionally entitled, “The Indirect Evaporative Cooling Source Book”. This will include the specific project outputs as follows: 

  1. theoretical analysis results for the general performance of indirect evaporative cooling technologies,
  2. fundamental analysis results through thermal analysis and optimization,
  3. simulation tools for indirect evaporative cooling technologies,
  4. design guideline for indirect evaporative coolingtechnologies, and
  5. feasibility analysis of indirect evaporative cooling technologies.


Operating Agent

Dr Xiaoyun Xie
Associate Professor
Tsinghua University
Building Energy Research Center, Department of Building Science
School of Architecture
100084 Beijing
Tel: +86 10 6279 3591


Algeria, Australia, Belgium, China, Denmark, Egypt, France, Turkey, United States of America