Town Hall House trigeneration

The City of Sydney's rooftop trigeneration system produces low-carbon energy to power, heat and cool Sydney Town Hall and its staff offices in Town Hall House.

The plant started full operations in October 2016 and it supplies the City's civic buildings on working weekdays from 7am to 10pm. The 1,400 kilowatt system is expected to cut carbon emissions by more than 40,000 tonnes over its 30-year lifetime.

As well as meeting the weekday energy needs of Sydney Town Hall and Town Hall House, the plant is ready to export significant amounts of power to the electricity grid. This will help to manage peak power demands and defer costly investment in electricity network upgrades.

Trigeneration is more than twice as efficient as the coal-fired power stations that produce around 80% of Sydney's electricity. Heat created from coal-fired power stations is wasted but trigeneration captures and uses it for air-conditioning, heating, hot water services and is converted into chilled water for air-conditioning.

The project is contributing to Sustainable Sydney 2030 by reducing the City’s yearly carbon emissions by 3% and reducing energy bills for Town Hall and Town Hall House by an average of $140,000 per year over the life of the project.

The project was partly funded with a grant from the federal government's community energy efficiency program.

Trigeneration produces local electricity and uses the waste heat for heating and cooling. Trigeneration and renewable energy will mean zero reliance on coal-fired energy. Trigeneration, helping us achieve a 70% carbon emission reduction by 2030.

How trigeneration works

The 'tri' in trigeneration refers to 3 simultaneous outputs from gas-fired generators: low-carbon electricity, hot water to heat buildings and chilled water to cool buildings.

A generator (typically powered by a reciprocating engine or turbine) running on natural or renewable gases (for example, from biomass) produces low-carbon electricity. The waste heat from generating electricity is captured to make hot water.

Hot water can be used for heating and it can also be converted to chilled water for air-conditioning by a secondary piece of equipment called an absorption chiller. Hot water and chilled water can be distributed to nearby buildings through a network of underground pipes. 

Trigeneration saves money

Trigeneration is an extremely efficient decentralised energy technology where electricity is made near where it is used, avoiding the need to bring electricity over long distances. It replaces coal-fired electricity and reduces emissions from buildings connected to the trigeneration system.

Producing energy locally helps avoid expensive upgrades to the NSW electricity grid of poles and wires which have pushed up power prices. 

Consumers are forced to pay for upgrades to an aging and inefficient network that moves coal-fired electricity from the Hunter Valley to Sydney.

The worldwide trend

Trigeneration is not new.

The first public electricity supply in the world was the cogeneration system, implemented by Edison in 1882 to supply electricity and steam to Manhattan.

This was later converted to a trigeneration system and is now the eighth largest decentralised energy network in the world.

Many European cities have been retrofitted with decentralised energy networks including Berlin, Copenhagen, Stockholm, Helsinki, Vienna, Hamburg, Gothenburg, Paris, Moscow, St Petersburg, Turin, Barcelona and London.

Trigeneration already operates in many properties across Sydney including commercial buildings such as Qantas, Google, 1 Bligh Street, 133 Castlereagh Street and 20 Bond Street. It also operates at leading community clubs such as Rooty Hill RSL, Castle Hill RSL and multiple councils such as Hornsby, Leichhardt, North Sydney, Willoughby and Wagga Wagga.

Please note: Our trigeneration master plan is a supporting document to our Environmental Action 2016–2021 strategy and action plan, which is the City's most up-to-date set of environmental targets and actions.

Last updated: Thursday, 13 July 2017