The City of Melbourne and City of Sydney have been declared joint winners of the building energy efficiency award at the C40 Cities Awards in Mexico City, thanks to the CitySwitch Green Office Program.

The awards were held as part of the C40 Mayors Summit, and recognise best practice in reducing carbon emissions and tackling environmental challenges.

“Melbourne and Sydney are occasional rivals on and off the sporting field but collaborations like CitySwitch show how our two cities are working effectively and collaboratively to preserve and generate energy,” Melbourne Lord Mayor Robert Doyle said.

Over the past year, 618,000 square metres of office space joined the program including new tenancies and existing signatories that had expanded their space bringing the total commercial office space engaged with the program to over three million square metres, Sydney Lord Mayor Clover Moore said.

In 2016, signatories carried out almost 1500 environmental projects, reduced carbon emissions by 57,871 tonnes and purchased 323,970 tonnes in carbon offsets. They have also saved $13 million in energy costs through reducing electricity use by 60 million kilowatt-hours.

The results go beyond saving money however.

“The outstanding leadership and action from our business community demonstrates that the market takes sustainability seriously, and their results contribute to the ambitious environmental targets in each of our cities,” Ms Moore said.

Mr Doyle said the program was one of a series helping the city work with businesses as part of achieving the goal of net zero emissions by 2020.

“We have 150 offices covering more than 700,000 square meters in Melbourne committed to reducing their environmental impact through CitySwitch. This is equal to the area covered by 35 MCGs and represents 70,000 city workers,” Mr Doyle said.

”We are pleased that C40 has recognised CitySwitch with this prestigious award and hope it will encourage other businesses to get on board.”

Frasers Property is one of the program’s current 571 signatories.

Frasers general manager of sustainability Paolo Bevilacqua said participating in the program had led to better environmental performance in the company’s offices, and also educated staff about things that can be done both in their own private homes and within the company’s development projects.

“It is a world class example of governments at all levels supporting businesses large and small to implement meaningful change for the benefit of their business and the environment,” he said.