Australian cities are among the world’s most sprawling and least affordable cities. Our continent is water scarce, and our grid one of the most carbon intensive in the world. Affordability – Density – Resource Efficiency – Amenity – these are interconnected foundational elements of successful cities of the 21st century. Cities must become more resilient to the physical, social, and economic challenges that are a growing part of the 21st century; they must incorporate a view of resilience that includes not just the disasters – floods, earthquakes, fires – but the stresses that weaken the fabric of a city on a day-to-day basis.

While livability in Sydney is rated one of the highest globally, the challenges of increasing density and maintaining amenity are substantial. Furthermore, our city utilities were never envisioned for the compact cities now required to remain globally competitive. As a nation and a city, new models of urban innovation are needed to enable the kind of renewal that will keep Sydney at the pinnacle of global cities.

The Central Park Project in Sydney seeks to provide a blue-print for addressing these challenges for urban Australia, servicing increased density with low-impact energy and water systems while improving public amenity and liveability. The new model for urban infrastructure implemented at Central Park, a mixed-use urban renewal project comprised of residential, student accommodation, commercial office, retail and public space components, can be a crucial enabler in addressing the scale and nature of urban renewal development needed across Sydney.

WSP was involved from the project’s conception and provided integrated services (with an environmentally sustainable design focus) that included: mechanical, electrical, hydraulics/plumbing, vertical transportation, fire safety and fire protection, and energy and water assessments.

The Project

Central Park (the former Carlton and United Brewery Heritage site) is in the central business district (CBD) of Sydney, anchoring a broader development site with the University of Technology, Sydney (UTS). Delivered by Frasers Property Australia and Sekisui House Australia, the project demonstrates the developers’ aspirations to create an environmentally sustainable urban precinct through a combination of certified green buildings, green public domain, and sustainable district utilities infrastructure.

The Central Thermal Plant is the engineering heart of Central Park and a prime example of a project that provides strong benefits in three areas: sustainability, liveability, and resilience. It is a fully integrated thermal energy, electricity and water utility system, enabled by a ground-breaking precinct governance framework and financed by one of the first low-carbon environmental upgrade agreements (EUA) in New South Wales (NSW), and it has pioneered the delivery of district infrastructure in an urban regeneration context.

The precinct utility provides affordable, low-carbon energy and a reliable and sustainable source of non-potable water through a 20MW central thermal plant, 2MW tri-generation and 1ML/day district water recycling and re-use system.

Project Innovation

The Central Park utilities infrastructure is a complex engineering feat of electrical, gas, and thermal energy and potable, recycled and stormwater management. The integration of these systems with a complex, multi-user community is a first, and it has required collaborative innovation by the design, construction, and commercial teams:

• Technical Innovation: The phased delivery of precinct thermal energy systems and the first low-carbon ‘green transformer’ tri-generation system in Sydney has developed new expertise in the design and construction sectors in Australia. Furthermore, constructing a utility hub within a spatially constrained urban precinct has proven an enabler for similar systems to be delivered more efficiently across the Australian market.
• Governance Innovation: The implementation of shared thermal services has required innovation in governance frameworks to create a functional market for thermal energy between disparate ownership and stakeholder profiles including the developers, Department of Planning and Infrastructure, residents, and tenants (residential, commercial, and retail). Central Park provides for reform in the broader energy market to allow both thermal energy retailing and embedded generation.
• Commercial/Financial Innovation: The financial innovation of the environmental upgrade agreement (EUA) process for infrastructure finance servicing multiple buildings (including complex ownership and heritage considerations) is a first and has revolutionized the urban infrastructure market in Australia. It has led to a much broader uptake of low-carbon energy funds from major financial institutions.

Resilience Aspects

The project has been designed with resilient features which include the following benefits and mitigation aspects:

• Delivery of affordable, low-carbon energy: this provides mitigation against climate change and it offers resilience to the economic cost-of-living pressures on its residents and commercial businesses.
• Central thermal plant: the CTP remains as a standalone autonomous “box”, minimising reliance on the local electrical grid. This arrangement requires careful thought into the system arrangement and system drivers to ensure that the tri-generation plant will be fully utilised and all outputs balanced.
• Thermal energy storage: this process of storing redundant thermal energy that is generated by the tri-generation system and thermal plant to use at a later time reduces the need and size of energy infrastructure normally designed to satisfy peak demand, for example, it reduced the number of required electric chillers from 32 to 8; the number of boilers from 24 to 5; and the number of cooling towers from 24 to 12. For resilience, a back-up emergency power system is provided for the plant room.

• Separating thermal and electrical networks: this principle long established in Nordic countries, global leaders in urban sustainability, enables both the improved feasibility of renewable energy on the electrical network side (by reduced demand and improved load consistency) and the opportunities for waste-heat capture for thermal networks. Both these approaches are front-line strategies in reducing reliance on fossil fuels and reforming the energy sector. Large-scale energy sector reform is a crucial element in successfully addressing climate change. The outputs of the CTP fall under the categories of electrical and thermal output:

• Electrical output – utilised to supply the conventional electrical chillers, pumping equipment, cooling towers and plantroom lighting; and

• Thermal output – utilised for space heating, domestic hot water and for the generation of chilled water by the absorption chiller plant.

• Cooling/heat rejection: the water-cooled electric chiller plant has been optimally configured to achieve a high operational efficiency through effective load matching with the cooling demand profile of the precinct. The modularity of the electric chiller plant ensures sufficient resilience in case of breakdown and routine maintenance, inclusive of the absorption chiller plant configuration.
• Recycled Water Treatment Plant (RWTP): low total dissolved solids (TDS) make-up water will be sourced from the RWTP to serve the cooling towers, which will be backed up by the Sydney water mains.

Summary

The Central Park CTP is an exemplar project for urban utilities, changing the paradigm for our management of urban energy and water networks.

• It integrates cutting edge technology across energy and water systems; shared thermal services, tri-generation, private electricity networks, waste-water treatment and sewer mining to deliver low-carbon energy and low-impact water to residents, commercial tenants, building owners and the public domain.
• The CTP is a highly complex industrial-scale utility delivered in a dense urban precinct without compromising visual or environmental amenity.
• It has tested the governance structures of energy market regulation, and broken new ground in the reticulation and commercialisation of thermal energy networks in Australia.
• It has leveraged innovative finance mechanisms – the first environmental upgrade agreement and first low-carbon fund in Australia – to be wholly privately funded.
• It has delivered on the triple-bottom line, engineering that serves people, profit, and planet.