In Sydney, Australia, buildings contribute over 50% of the city’s greenhouse gas emissions. Traditional buildings are powered by coal-fired power stations that produce around 80% of Sydney’s electricity.
In contrast, a tri-generation plant generates electricity onsite using a gas engine, which is twice as efficient as coal-fired power stations and reduces carbon emissions by approximately 40%. The generation efficiency is further enhanced by the utilisation of waste heat for heating and chilled water generation via an absorption chiller.
A highly efficient energy technology, the tri-generation system is one of the largest decentralised energy networks in the world. As electricity is produced onsite, near where it is used, there is no need to transport electricity over long distances. It can replace coal-fired electricity and reduce overall emissions from buildings.
The tri-generation plant at Keppel REIT’s 8 Chifley Square comprises a 400 kW MWM TCG 2016 V8 natural gas engine connected in parallel to the grid. The engine is coupled to a 255 kW Broad exhaust fired absorption chiller that is fully integrated into the building’s air conditioning, chilled and condenser water systems. Additionally, the tri-generation plant can produce 212 kW of heating for use by the building’s heating, ventilation, and air conditioning systems.
The tri-generation plant operates only during periods of high demand. During off-peak periods when the building requires lesser energy, electricity can still be purchased from the grid to ensure the building achieves the optimal environmental and financial efficiency.
The plant is the first of its kind in Sydney that is able to export “excess” electricity generated to another property. This allows the plant to operate at a higher capacity over longer periods, improving efficiency, minimising material use and redundancy and providing low carbon electricity to other buildings, which in turn greatly reduces overall carbon emissions.
On average, the tri-generation plant at 8 Chifley Square produces 22,599 kWh of electricity every week, or approximately 1.18 million kWh per annum, enough to power about 7,320 homes in Australia for a year.
The use of onsite generation rather than grid-based electricity has also resulted in a reduction of 1,234 tonnes of carbon dioxide, the equivalent of emissions emitted by a car travelling over six million km.
The tri-generation technology is recognised under Australia’s Green Star Design as a carbon and demand reduction initiative. This has gained 8 Chifley Square additional credits for its 6-star design and as-built ratings, and supports its goal of a 5-star energy rating under the National Australian Built Environment Rating System.
Ms Ng Hsueh Ling, CEO of Keppel REIT Management, said, “At Keppel REIT, we believe that resource efficiency is not only our responsibility, but also makes good business sense.
“In line with our commitment to embrace sustainability, 8 Chifley Square is testament to how we can leverage innovative technology to achieve real cost savings while making a significant positive impact on our environment.”