Carbon neutralisation of commercial property

Retrofitting for energy efficiency

With Queensland businesses reeling from a progression of double-digit electricity price hikes in recent years combined with a highly competitive commercial property rental market, many property owners are looking for a new competitive edge to help attract increasingly discerning tenants who are seeking smart ‘green’ buildings with low electricity consumption.

When considering the refurbishment of their commercial property at 23 Edgar Street in the inner Brisbane suburb of Bowen Hills, the Saunders Havill Group engaged VDM Consulting engineers to ensure that their property’s energy efficiency upgrade took into account the future needs of tenants, together with proposed federal government law on Mandatory Energy Disclosure Statements.

At the time of developing the project the federal government’s Carbon Pollution Reduction Scheme (CPRS) was still under consideration by the Senate, with the launch of the Green Building Fund promising grants of 50% of eligible capital expenditure on energy efficiency upgrade items up to $500,000 in total.

It was for this reason that the energy efficiency upgrade scheme was entitled ‘23 Edgar Street Carbon Neutralisation Project’ with a focus on the upgrade of major energy consuming items in the property such as heating, ventilation and air conditioning (HVAC), lighting and water heating, together with installation of sufficient solar photovoltaic (PV) power at the site to neutralise the carbon emissions associated with the remaining electricity consumption at the site.

New sub-metering was also specified for the HVAC and lighting circuits to enable ongoing monitoring of the electricity consumed by these items, together with upgrade of the building facade with new awnings to help reduce direct sunlight penetration and installation of radio frequency controlled GPO units to shut-off all office equipment at night and weekends. Simple time clocks were also installed on water boilers and filtration units as well as presence detectors for the control of all lighting circuits, except the emergency lights.

VDM Consulting completed the Green Building Fund documentation on behalf of the client, including a NABERS audit for submission to AusIndustry in order to demonstrate projected energy savings in excess of 50%. A generous grant of approximately $140,000 was awarded from the federal government which will see the balance of the owner’s capital expenditure achieve a payback period of approximately three years, based on AS 3598 assessment methodology, and provide considerable advantage in the commercial property rental market.

Given the fact that at least 10% of Australia’s greenhouse gas emissions come from commercial office blocks and that the high energy density of typical CBD high-rise office blocks preclude the use of rooftop solar PV systems to achieve carbon neutrality, it would appear that the 23 Edgar Street project is a model for what the emerging ‘retrogreening’ market should be seeking to achieve via the upgrade of older low-rise commercial offices in the fringe CBD areas around major capital cities. Recent moves to gross feed-in tariffs in the ACT and New South Wales mean that owners of older low-rise commercial offices in fringe CBD areas in these jurisdictions can use their rooftop solar PV systems to further improve payback periods for energy efficiency upgrade projects in conjunction with available government grants and commercial eco-efficiency funds.