Turning Waste Heat Into Air Conditioning

The Combined Heat and Power plant jointly developed by A*STAR and Hitachi achieves high efficiency with low operation costs.

AsianScientist (Aug. 29, 2014) – Imagine powering a building’s air-conditioning using heat. The Experimental Power Grid Center (EPGC) at Singapore’s Agency for Science, Technology and Research (A*STAR) and Japanese electronics company Hitachi have now completed and commissioned a Combined Heat and Power (CHP) pilot plant to harness waste heat, and convert it to energy to power air-conditioning.

The CHP system will control heat and power facilities as the operating point to best minimize costs and energy consumption. The plant marks the successful completion of a milestone in the three-year research collaboration project between EPGC and Hitachi.

CHP systems are not widely adopted in Singapore as most buildings obtain power from the grid to provide electricity for air-conditioning, mechanical ventilation systems, water pumps, lights and other services such as lifts and escalators. These needs account for up to 54 percent of total electricity consumption in a commercial building.

With the large electricity consumption, there is a need for an energy efficient system that decreases reliance on fossil fuels and reduces carbon dioxide emissions. This is crucial as buildings are estimated to contribute almost 14 percent of Singapore’s carbon emissions by 2020.

When a CHP system is integrated into a building, a generator need not perform at full capacity as excess heat is now used to power air-conditioning. The building now has the ability to produce and control both electrical power and heating and cooling services required to power air conditioning, thus increasing energy-efficiency. EPGC and Hitachi estimate an increase in energy efficiency from 36 percent with just a generator, to 52 percent with the implementation of this integrated system.

The simulation software developed in this project can simulate various building system configurations. This enables consultants to implement the best control strategy resulting in optimal performance, thus improving energy savings even before a building is built.

Mr. Kunizo Sakai, president & CEO of Hitachi’s Infrastructure Systems Company said, “We will commercialize the CHP control systems in 2015 based on the results obtained through this joint research and provide solutions of increasing energy-efficiency and reducing carbon dioxide emissions with lower cost for buildings and factories, primarily in Asia.”

Associate Professor Ashwin M. Khambadkone, program director of EPGC said, “With the commissioning of the advanced CHP pilot plant, EPGC is able to provide a platform to further research in energy efficiency in buildings. The CHP pilot plant further supports the Building to Grid (B2G) concept, enabling buildings to act as virtual power plants.”

Building to Grid (B2G) is a concept that leverages on a building’s capability to generate electricity on its own for the building’s needs through embedded generation. The building will then become a grid in itself, also known as a microgrid. When many building microgrids with CHP systems are connected to the power grid, these buildings are now able to power the grid and potentially supply excess electricity power to the grid.

The integration of CHP system into the B2G concept enables the building to act as a virtual power plant. This enhances the grid’s resilience to function independently and decreases reliance on the main power grid, which is useful during emergencies or disasters. With B2G, the grid can respond faster to load changes, allowing more intermittent renewable energy to be integrated into the grid.

The CHP pilot plant will function as a platform for experimental support to explore new research ideas for potential energy savings benefits, and study the feasibility of robust energy management and control system under various weather conditions, for greener buildings in Singapore.


Source: A*STAR.
Disclaimer: This article does not necessarily reflect the views of AsianScientist or its staff.

Asian Scientist Magazine is an award-winning science and technology magazine that highlights R&D news stories from Asia to a global audience. The magazine is published by Singapore-headquartered Wildtype Media Group.

Related Stories from Asian Scientist