ECOS 2020, the 33rd conference, will be held in Osaka for the second time in Japan. The purpose of the conference is for participants to present new research results and exchange views on performance, economics, and environmental impact of various energy systems. We cordially welcome you to Osaka from all over the world. We expect that you will enjoy a fruitful week through the conference and Japanese local cultures.

Topics Addressed include:

• Refrigeration, air-conditioning, and heat pumps
• Power generation and CHP
• District energy supply and networks
• Energy use (buildings)
• Basic and applied thermodynamics
• Heat and mass transfer
• Energy use (transportation, desalination, etc.)
• Industrial energy use
• Energy conservation and management
• Environmental impacts of energy conversion
• Energy policy and planning
• Renewable energy (solar, wind, hydro, etc.)
• Energy storage (batteries, thermal, hydrogen, etc.)
• Distributed generation and smart grids
• Fuel cells
• Energy/exergy analysis and optimization
• Process integration, analysis and optimization
• ORC and low-grade thermal energy recovery

A Brief History of the ECOS Conferences

ECOS is the name of a series of international conferences that focus on modern aspects of Thermal Sciences with particular emphasis on Thermodynamics and its applications in energy conversion systems and processes. The idea for the ECOS series of conferences originated at the meeting of the Systems Analysis Technical Committee (SATC) of the Advanced Energy Systems Division (AESD) of the American Society of Mechanical Engineers (ASME) during the 1985 ASME Winter Annual Meeting (WAM), in Miami Beach, Florida, under the leadership of Prof. Richard Gaggioli. At the meeting it was decide to:
- organize an annual Symposium on the Analysis and Design of Thermal Systems at each ASME WAM, andtry to involve more  - scientists and engineers from outside the United States by organizing conferences in other countries, except the United States.

Indeed, a Symposium of 8-15 sessions has been organized by the SATC every year since 1985 at the ASME Winter Annual Meeting and its successor, the International Mechanical Engineering Congress and Exposition. The first overseas conference took place in Rome, in 1987, with the support of the U.S. National Science Foundation. The name ECOS was used for the first time in Zaragoza, in 1992. It is the acronym for

Efficiency, Cost, Optimization and Simulation

of energy conversion systems and processes, keywords that best describe the contents of the presentations and discussions taking place in these conferences. It is worth noting that “ecos” means “home” in the Greek language and it is used here with two meanings:

• the earth as our home we need to protect, and
• the conference as a home for a fruitful exchange of our ideas.