Trigeneration

Trigeneration

Town Hall House trigeneration

The City of Sydney plans to reduce our greenhouse gas emissions by 70% by 2030 – trigeneration could help us reach this goal.

We are investigating the installation of a low carbon trigeneration plant that would produce clean local power, heating and cooling for Sydney Town Hall and the neighbouring Town Hall House where over 1,500 City employees work. Hundreds of lights, printers, computers, air conditioners and the City's electric vehicle fleet would be powered by the plant.

Trigeneration is more than twice as efficient as coal-fired power stations that produce around 80% of Sydney's electricity – heat by-products created at coal-fired power stations are wasted but trigeneration captures and uses them for air-conditioning, heating and hot water services. Installing trigeneration at Town Hall House would allow for future expansion to the nearby Queen Victoria Building, and potentially other buildings in the area.

How trigeneration works

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

A trigeneration engine runs on natural or renewable gases producing low-carbon electricity. The engine, which is about the size of a shipping container, generates heat that is captured to make hot water.

Hot water can be converted to chilled water for air-conditioning by a secondary piece of equipment called an absorption chiller. Hot water or chilled water, called thermal energy, 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 connected buildings.

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.

In the Asia/Pacific region, Seoul has the third largest decentralised energy network in the world.

Last updated: Thursday, 27 February 2014