Australia punches above its weight when it comes to constructing sustainable commercial buildings.
Infrastructure has a key role to play in sustainability and investors pumping money into the buildings many of us work in are demanding greater efficiency.
One of the ways we can rate sustainability is through the Green Building Council of Australia's Green Star rating system.
It's an internationally recognised scheme that assesses things like design, construction and operational performance.
It uses a six-star rating system starting from one star which implies that a building meets minimum practice all the way up to 6 for world leadership.
While it's still under construction, Lend Lease Group Head of Sustainability, Geoff Dutaillis, says Barangaroo, on the western edge of Sydney's CBD, will be Australia's first large scale carbon neutral community.
"It'll be capable of exporting more water than it uses, it'll generate enough renewable energy to power the black water treatment plant in the public domain and it'll be net zero waste to landfill," says Mr Dutaillis.
Lend Lease is developing the precinct, and while some of it is still under contruction, International Tower 2 is now open.
Geoff Dutaillis says it has been given six green stars.
"Green simply means being more efficient with the use of resources, and creating healthier places for people. It's not just about the buildings - it's about the people in the buildings and green needs to work for them. We would have not attracted the tenants or investors we have without being green."
Westpac and St George are major tenants. Their employees enjoy sustainable features like LED lighting and a state of the art bicycle hub.
Geoff Dutaillis says the real action happens further underground.
"It has a harbor heat rejection system to cool the towers which removes the need for cooling towers and reduces dramatically the use of energy and water."
It's the largest such structure in Sydney.
Fifteen gigalitres of sea water will stream from Sydney Harbour through a series of pipes every year rejecting the heat emitted by the building's air conditioning system, negating the need for less efficient cooling towers.
Romilly Madew CEO of the Green Buildings Council of Australia (GBCA) says long term, it can save costs.
"The cost is really on water efficiency if you think of Australia being the driest continent but also it has proven beyond a doubt that the energy efficiency of buildings has a long-term payback."
The business case for energy efficient buildings is clear.
"We know that green-rated buildings deliver up to a 30 per cent premium over non-rated buildings. It does this through higher rental rates, lower occupancy costs, better tenant attraction, which delivers higher yields and lower cap rates on valuation."
The GBCA's Romilly Madew says Australia is leading the way when it comes to green office buildings, but that investors demand it.
"Globally we punch above our weight. So there is a global sustainability benchmark and Australia has been leading for the last five years. Not only that, the differential between that and the global average has been increasing, and what that global benchmark is, is what investors use to look at the performance of portfolios."
Twenty-three per cent of Australia's CBD office space is now Green Star-certified and it's not just new buildings being achieving green status.
The Sydney Opera House was awarded four green stars in September.
Naomi Martin, Sustainability and Energy manager at Sydney Opera House says the structure got points for energy efficiency.
"We achieved a 10 per cent saving in electricity use over the last five years. We've done that through lighting upgrates throughout theatres, for example the concert hall and also the back of House areas."
It also uses green cleaning techniques like olive oil to maintain much of the bronze inside the structure and uses baking soda to clean the concrete outside.
Like International Tower 2, the sea water is also used to cool the Sydney Opera House.
"We also got points for a range of social sustainablity measures like our Reconciliation Action plan, and accessability plan for access to all," adds Naomi Martin.
Residental developers are also seeing the benefits of going green like Melbourne's Forte complex which Lend Lease's Geoff Dutaillis says is the world's tallest residential timber building.
"A timber-constructed building is safer to build, and quicker to build, in operation, it's more efficient and creates a more healthier environment to live in."
The green industry's challenge now is to convince retail players of the benefits of investing in sustainable initiatives.