A commercial building uses Australian technology to hit the NABERS rating for a six, Phillip Ross reports.
The completion of the latest Local Government Super (LGS) commercial property is a flagship project for Australian technology becoming the lowest emission office building in Australia.
The 25-year-old commercial building in North Sydney has been retrofitted to a 6-star rating from NABERS (one of only two projects in the country) while remaining fully occupied during the upgrade. Haden were contracted to provide design and construction services for the retrofit.
Look up in the sky
The state of the art trigeneration project used Australian technologies such as the Shaw Method of Air Conditioning (SMAC), Envirolight E1 lights, Bennett Clayton alternative fuel engines and Power Pax chillers as key parts of the refurbishment.
As a result, the building’s emissions have been reduced by approximately 85 per cent and it is expected to operate 100 per cent independently of the electricity grid within the first year following completion.
The cost of these improvements was approximately half of what is estimated to reach a 4.5 star NABERS rating.
Peter Lambert, chief executive officer of Local Government Super noted “commercial buildings can use up to 30 per cent of city energy requirements and are a major contributor to greenhouse gas emissions. Many owners consider it too difficult to retrofit an older office building, citing cost constraints, both from the refurbishment and the loss of income if the building tenants were disturbed or had to be relocated during the works,” Lambert says.
76 Berry Street was recognised in 2010 as an ‘Exemplar project’ by the Federal Government’s Green Building Fund, including a $2.1 million grant towards the
full refurbishment budget of $6 million.
Recently it has attracted the interest of the World Economic Forum and Maastricht University which are in discussions with LGS about implementing the lessons learned from the project into best practice guidelines for organisations to follow globally. At the launch of the building the World Economic Forum’s Robin Read said the project shows that this sort of upgrade can be done on a global basis and that Australia should be “exploiting the technology and the expertise as an export commodity”.
The aim of the project was to establish the most effective overall package of retrofit measures necessary to deliver the lowest emission commercial office building in Australia. It is a world first using Australian technologies and carrying out the upgrade while the building remained fully occupied.
The building comprises two levels of basement parking, lobby and retail areas, including a coffee shop, restaurant and landscaped gardens and 10 levels, totalling 11,500m2, of office accommodation. It was constructed in 1985 and operates at 4.5
stars. Local Government Super has signed a commitment agreement for operation at 6 star NABERS Energy. It is the only existing office building currently under this type of commitment agreement.
The project will have emission levels over 85 per cent lower than the average commercial office building. We believe that it will be the lowest emission office building in Australia and, possibly, the world.
More powerful than a locomotive
This is the first use of Australian-made Bennett Clayton engines in a commercial building. The engines run on LPG and deliver improvements in fuel efficiency, power and reduced emissions over diesel engines. The engines are multi-fuel capable so, if bioethanol or biomethanol becomes an available fuel source for the building, it can convert to these in the future. The engines are remanufactured from a diesel to a natural gas engine in Deniliquin NSW. The engines don’t just provide the carbon emission reduction capability for the site, they also emit undetectable levels of exhaust emissions in areas like sulphur oxides, nitrates and particulate matter.
The engine system consists of five 100Kw units, allowing for redundancy and ensuring capacity. The building can run at all times on gas at high or low loads. This enables the building to not rely on the grid for power but can switch to the grid if ever required.
Able to cool tall buildings
Haden was the lead contractor responsible for the upgrade design, construction and delivery.
As part of the project, Haden replaced the existing direct expansion cooling system with
a high-efficiency chilled water system.
“We are extremenly proud to have been involved in this ground-breaking project,”
said Haden chief executive, Mark Williamson.
The concept of the project was to reduce the heat load through a whole of building lighting upgrade, replace the HVAC system with the most efficient available and reduce emissions.
The unique five 100kW engine system used for the trigen now provides capability to deliver small generation systems to commercial building where load profiles previously would not allow a trigen system to operate.
The new chiller installed is a Melbourne manufactured Power Pax chiller, utilising the oil-free Turbocor magnetic bearing compressor.
Outdoor air was induced into the existing internal zone air handling via the introduction of the Shaw Method of Air Conditioning (SMAC). Additional heat exchangers, piping and control strategies are added to manage indoor air comfort conditions.
SMAC uses a combination of humidity and temperature control to provide a more productive working environment while reducing the HVAC energy consumption from between 30 to 85 per cent depending on the application.
Trigeneration has replaced the existing source of electrical supply to on-site generation from gas. The waste heat is then used to substitute into other building services. Air conditioning chillers are supplied with chilled water from Broad absorption chillers using the reclaimed heat.
A fully integrated building management control system includes a web interface to inform tenants of the buildings energy usage and savings.
This is a job for LGS
LGS has a policy to aim for a NABERS 5 star energy rating or better on all its properties in its portfolio.
It has already upgraded five commercial buildings progressively using the experience gained to adapt tried and tested energy efficient technologies to each new upgrade.
While all its buildings use green power, this is not taken into account on its NABERS rating. Brian Churchill, LGS property portfolio manager says the challenge has been to design, manage and deliver the upgrades in occupied buildings without disturbing tenants to avoid the loss of rental income.
The Green Building Fund has committed $118m to 318 upgrades since inception. A stipulation of the grant is that there must be full information sharing and it has been shown that the fund is saving at least 300,000 tons of CO2e per year. 65 projects have been evaluated on average to be achieving 27 per cent emission reductions, better than projected.