For more detailed information on this techology transfer, please refer to original project documents under the documents section below.
Cooling is becoming a rapidly emerging demand in developing countries, which signifies that the building design and shell measures need to reduce cooling loads, and the efficiency of air-conditioning will need to be improved. Air conditioning systems are implemented in numerous sectors, namely buildings, industry and transport. They are distinguished in two main categories, room air conditioners and central air conditioners.
The Global Environment Centre Foundation (GEC) is an entity that supports the UNEP’s International Environmental Technology Centre (IETC), based in Japan. GEC is dedicated to the transfer of environmentally sound technologies, in both developing countries and countries with economies in transition. The foundation aims to contribute to Japan’s international efforts on the environment, sharing project collaborations as well as promoting Japan’s rich conservation knowledge and experience in developing nations.
Background: The proposed system dehumidifies the air and uses its energy for water heating. The condensed water can subsequently be given back to the dried air in an evaporative cooling process; or when only dehumidification is desired it can be simply drained from the system. This unit can utilize the A/C latent load for domestic water heating resulting in significant energy savings for water heating and A/C. The system can control humidity in residential buildings resulting in comfort and significant health benefits.
The technology is an energy efficient water purification method that can be used for large-scale commercial application. The process works by boiling the contaminated water to destroy the presence of bacterial or parasitic organisms and then instantaneously cooling it. It uses CO2 as the heating agent as well as the refrigerant. In a heat exchanger compressed CO2 is used to boil water to 116 ˇ C destroying any harmful bacteria. The water is then cooled in a radiator by using a fan. The liquid CO2 is throttled to reduce its pressure and subsequently cooled to around 5ˇ C.
A proton exchange membrane (PEM) fuel cell is an electrochemical device that produces “clean” electricity from a chemical reaction between hydrogen and oxygen with only water and heat as byproducts. Mismanagement of the heat generated in the cells drops performance and jeopardizes reliable and safe operations.In a classic system the coolant controls for a PEM fuel cell stack uses a feedback control that is based on the actual temperature value measured at the outlet of the coolant channel. This is known as a “bang-bang” or proportional-integral (PI) controller.
Research at the University of California Berkeley has led to the development of an innovative approach that addresses the material issues which have traditionally prevented the use of closed gas power cycles with liquid metal and molten salt coolants. Design calculations that apply these innovations have shown that cycle thermal efficiencies comparable to current helium-cooled reactor designs (> 45%) can be achieved using turbomachinery equipment and operating parameters very similar to those for current helium cooled high-temperature gas reactors.
This fact sheet provides current information on low global warming potential (GWP) alternative refrigerants to high-GWP hydrofluorocarbons (HFCs) for use in domestic refrigeration equipment. HFCs are powerful greenhouse gases (GHGs) with GWPs hundreds to thousands of times more potent per pound than carbon dioxide (CO2 ); however, more low-GWP alternatives are becoming available.