Summary

The City of Melbourne is generating 252,000 kilowatt-hours of electricity each year from what is the largest urban solar installation of its kind in the Southern Hemisphere. Housed on the roof of the historic Queen Victoria Market, the system has cut CO2 emissions by 1,314 tons since it was installed in 2003, and is providing enough energy to power 46 homes a year. The installation showcases the benefits of renewable energies to the public and tourists with a real time display on-site of kWh generated and CO2 emissions saved. Importantly, it demonstrates that solar can be applied to historic buildings and dead urban spaces such as rooftops.

What is it?

The largest urban grid-connected solar photovoltaic installation in the Southern Hemisphere, harnessing energy from 1,328 solar panels on the roof of a heritage building in Melbourne, Australia.

How does it work?

Photovoltaic system

  • The panels convert sunlight into d.c. electricity and then the electrical current is distributed to one of 83 solar inverters located under the eaves of the Queen Victoria Market.
  • The inverters are used to convert the d.c. to a.c., so the power is the same as normal grid power.

Installation

  • More than 1,300 solar photovoltaic panels were installed on one third of the Queen Victoria Market’s roof.
  • Each laminate measures 1.59 meters by 0.79 meters. It took one year to install.
  • The a.c. power from the inverters is distributed to the main switchboard where it can be used by the Queen Victoria Market.
  • During the day, the electricity will be distributed within the market. At night, when the solar panels are not generating electricity, the market consumes electricity from the national grid.
  • The PV solar panels will generate power for at least the next 30 years

Energy efficiency

  • The system generated 239,000 kilowatt-hours of electricity during the 2003-2004 financial year.
  • It saved more than 350 tons GHG emissions for the 2003-2004 financial year alone (based on Australian Greenhouse Office estimations that in Victoria, every kilowatt-hour of electricity generated by clean energy sources - sun, wind and water - abates an equivalent of 1.467 kilograms of greenhouse gases).

Application

Solar access

Australia is particularly well placed due to the hours of sunlight it receives:

  • Over a year Melbourne's annual average sunlight hours totals 6 per day. In the summer month of January, it experiences 8 hours
  • Sydney has an annual average of 6-7 sunlight hours. In the summer month of January it has 7-8 sunlight hours
  • Perth has 9 hours and 10-11 in the summer month of January
  • By chance, the existing roofing of the Queen Victoria market was orientated to the north – this combined with the natural tilting of the roofs, maximizes output from the panels and minimized installation costs.

Installation

  • The installation took one year to complete, it began in October 2002 and the task to assemble and secure the solar photovoltaic panels to the existing timber on the market roof was completed in March 2003.
  • The installers used a combination of scaffolding, roof barriers and a scissor lift to move the panels onto the roof, using equipment such as battery-powered hand tools and special clamps for handling the solar panels.

Public engagement

  • The historic Queen Victoria Market in the centre of Melbourne is the largest tourist attraction in Victoria. The popularity of the market makes it an ideal location to showcase renewable energy in an urban environment;
  • To help market visitors understand more about the project and solar power, the City, along with BP Solar and Origin Energy, have a permanent, real-time display on-site showing the latest power reading in kilowatts and CO2 emissions saved – go to: www.melbourne.vic.gov.au.
  • The readings are also available on the public viewing board located outside the food court in Queen Street at the Queen Victoria Market.