Cover, City of Sydney trigen masterplan

22 August 2012; updated 23 August 2012 . It was almost a revolt from the property industry. Last Thursday night’s Property Council of Australia forum promised an innocent enough low-down on the proposed trigeneration network for the city and how it could play the starring role in Lord Mayor Clover Moore’s grand plan to transform Sydney’s sustainability profile.

By Monday there was a letter from the council on the desk of every major property company chief executive. (See a copy of the letter obtained by The Fifth Estate, below.)

The plan is to cut electricity consumption, greenhouse gasses and reduce peak loads on the network by about 70 per cent.

So far so good. The industry specialists gathered at the forum voted a big thumbs up for the engineering work on the gas and electricity supply and network.

There was only one problem (well, maybe more than one): someone forgot to ask the property owners the right questions about how the supply of this low GHG energy would hook up to the buildings.

And this despite the City’s much vaunted Better Buildings Partnership, designed to do just that – consult, get property owners and council on the same page so that the low emissions outcomes would be achieved smoothly, at the lowest possible cost, and make everyone happy.

But that wasn’t the feeling.

According to our accounts, GPT’s Bruce Precious lit the fire. Others soon fanned the flames.

The main problem, the forum heard, is the plan’s proposal to use a hot water reticulation system for heat exchange, instead of a chilled water system.

The hot water system works by bringing hot water, produced by waste heat from electricity generation, to a building. An absorption chiller then converts the heat to chilled water for cooling.

In hot water over the chillers
Not so good. Opting for a hot water system would mean property owners would need to replace their regular chillers with absorption chillers, which are much bigger and heavier than the old models.

Moderator Steve Hennessy later summed up the content of the forum. These chillers, he explained, may not fit where the old chillers were, such as on the roof, which may not have load bearing capacity for the extra weight, or the space.

The new chiller might go into the basement but that means the pipes would need to be rerouted at significant cost.

There are other issues, such as how to attribute the greenhouse gas co-efficient of electricity produced by the gas fired trigen plants. Some of the owners fear that the costs of the trigen system might be too high.

By Monday morning, leading property companies and stakeholders had a letter on their desk, from the City’s chief executive officer Monica Barone, explaining the big picture and inviting feedback to the trigen masterplan. (See below.)

An imminent council election on 8 September, would have added a sense of urgency to her response.

The masterplan
According to Precious, the trigen master plan on display asks many questions, but also fails to answer many.

“The master plan doesn’t provide a genuine technical or commercial feasibility,” Precious said in an interview on Tuesday with The Fifth Estate.

Putting it politely, he said: “I think the industry is finding its way through the sources of information and misinformation and there’s a lot of sifting through of what’s real and what’s a pipedream”.

“The real analysis between energy producing and energy   transmission – what hasn’t been included ­– is the practicality of what’s needed to run buildings.”

The city’s plan by the way had been posted online several weeks ago ­– 20 July.

See the link at Trigeneration MasterPlan – City of Sydney

Precious said: “We have the opportunity now to comment and to the council’s credit it’s kept the Better Buildings Partnership advised of what’s likely to be in the master plan so we were able to digest it.

“We now have the opportunity to respond to the master plan in detail; a letter has been sent to a wide range of stakeholders making them aware of the master plan and inviting them to comment.”

Precious says he thinks the document is impressive and has “some marvellous analysis and some marvellous graphics – well constructed documents”.

But, he said, it was “pretty challenging to digest”.

In addition, its unusual format (almost landscape A3)

and a choice of multiple documents or single document with a massive 28.5 megabites of data in one hit, is cumbersome to access, he said.

(The Fifth Estate doesn’t think the PDF format very accessible. The “big Mac” struggled for an inordinate length of time to download the document; it seemed safer to quit before it was finished. Even the foreword, of 3.5 MB took such a long time that the computer fell asleep before the download was completed. A few wake up calls and we managed to finally view a very limited number of pages of the document. It was beautifully designed. The cover is reproduced above.)

In Hennessy’s view the proposal on a hot water system is probably a misstep.

“A lot of the building owners are comfortable with electric chiller technology and they’re not comfortable with absorption machines,”he said.

“In theory it should not be a problem; there are fewer moving parts but do have other issues.

“If you were to remove the absorption chillers from the equation, why doesn’t the City of Sydney generate chilled water; the efficiency of the chillers they use is much higher.

“The chilled water system has greater appeal to building owners.”

There’s another issue that is probably more significant than the technical difficulties, says Precious.

And that is that it is unclear what greenhouse co-efficient would be applied to gas fired trigen power generated off-site, for purposes of a NABERS rating, given that NABERS doesn’t recognise off-site greener power for its ratings.

This is under review, but there’s no certainty there will be a change any time soon.

It gets more serious.

What about the stars?
Precious says one of the case studies in the council’s masterplan, on pages 58-61 (which The Fifth Estate could not access to verify) “shows the building is unsuitable for connection to the hot water network for absorption cooling”.

“The first case study shows 0.5 star uplift if all electric chillers are replaced with absorption. ”

“In NABERS terms that means zero benefit.

“If the building purchases some of the light brown power from the gas generators it won’t be recognised by NABERS under current protocol.

“NABERS has clarification out for discussion, but it’s unlikely that it will favor this off-site cogen electricity in the near term.”

WSP Built Ecology associate Alan Davis, who also commented at the forum told The Fifth Estate in an article update on Thursday that it was important that NABERS address the emerging technology in its review currently under way.

“The burning issue is how NABERS addresses this situation and it is important that it catches up to developments in technology and catch up now.

“It needs to give surety to owners that if they connect there is a NABERS benefit.”

However, he said even a half a star improvement in NABERS is equivalent to around 25 per cent reduction in a building’s current greenhouse gas emissions.

“This is certainly no small feat. I would also add that the other key benefit to connection is around 25-30 per cent reduction in electricity bills.”

So how did the confusion about the proposals of the trigen system arise?

Questioned as to how much information was shared in the Better Building Partnership group, which he chairs, Bruce Precious, explained that it wasn’t so much a matter of not sharing the information as that the technology is new and challenging, especially in the current tough market conditions.

“The body of knowledge around this technology is not very thick on the ground. No-one has the experience of doing what the council is proposing. And given this market and this environment, nobody is absolutely sure how it could work,” he said.

The City is now preparing a demand management master plan. In retrospect, said Precious, this should perhaps have come first.

Following is a copy of the letter obtained by The Fifth Estate:

I write to invite you to view and comment on the City of Sydney Decentralised Energy Master Plan – Trigeneration (the Trigeneration Master Plan) which is on public exhibition until 10 September 2012.

In June 2008, after almost two years of consultation and planning, the City adopted Sustainable Sydney 2030 with targets to reduce greenhouse gas emissions by 70 per cent across our local government area and end reliance on coal-fired electricity by 2030. Currently, around 80 per cent of the City’s greenhouse gas emissions are from centralised power generation, primarily coal-fired power stations.

In addition to a number of measures to reduce emissions, Sustainable Sydney 2030 identified trigeneration as the principal and largest of the strategic actions that will, collectively, achieve the City’s emission reductions target.

Trigeneration is the simultaneous production of electricity through burning natural (or renewable) gas in an engine. The waste heat from the generation process is then used to supply heating and hot water needs of buildings. Through a further step this heat can then also be converted into cooling. Trigeneration would produce half the emissions of coal and avoids transmission losses.

Commercial buildings are the main cause of greenhouse gas emissions in our LGA and replacing gas heating and electric airconditioning with heating and cooling produced by trigeneration will also reduce emissions and pressure on the electricity network.

The City’s Trigeneration Master Plan identifies 477MWe (mega watt electrical) of local trigeneration potential. It would reduce greenhouse gas emissions across the LGA by between 24 per cent and 32 per cent, electricity consumption by 30 per cent and peak electricity demand by 60 per cent.

The plan shows precinct-scale trigeneration is the most cost effective way, after energy efficiency, to reduce greenhouse gas emissions in Sydney. It includes analysis by CSIRO showing air quality impacts from the proposed gas-fired generation are negligible. It also includes information from gas supplier Jemena showing how gas network augmentation can occur to supply the system.

Submissions are due by 6pm on 10 September 2012 and we would welcome your feedback and look forward to working with you to achieve success with this important and innovative program.

You can see more information on the Trigeneration Master Plan on the City’s website at Alternatively, should you or any of your staff wish to speak with a Council officer about the Plan, please contact Nik Midlam, City Carbon Strategy Manager, on 9265 9847 or at

Other Sustainable Developments

You may also be interested to know that the City is progressing a range of environmental projects. These include:

  • A contract underway with Solgen to install 1.4MWe solar photovoltaic systems across Council owned sites. This will provide about one quarter of the City of Sydney’s electricity needs.
  • A Building Energy and Water Retrofit contract with Origin Energy and Ecosave which is guaranteed to reduce energy and water consumption by 20 per cent and emissions in Council properties by 23 per cent, based on 2006 levels, by the end of 2012.
  • Replacement of 6,450 street and public domain lights with LED technology which will reduce street light electricity consumption and emissions by 51 per cent by 2014 with a simple payback within 10 years.
  • A trigeneration development agreement with Cogent Energy (a subsidiary of Origin Energy) for trigeneration energy services across the local government area that will supply 70 per cent of the City’s local council area electricity requirements by 2030. Trigeneration energy will also supply 100 per cent of Council’s energy requirements. The first plant should be operational by 2014.
  • An Environmental Upgrade Agreement worth $26.5 million with Frasers Property and The Australian Environmental Upgrade Fund to install trigeneration and thermal energy networks at the Central Park development.

Should you or your staff wish to speak to a Council officer about these developments, please contact [the City]

Yours sincerely


Chief Executive Officer