8 Feb 2013

Sydney Council's Gas Gamble

By Justin Field and Norman Thompson
Sydney City Council wants to install gas generators as part of its sustainability plan - but there are concerns the scheme could encourage coal seam gas development in NSW, write Norman Thompson and Justin Field
Sydney Council's Sustainable Sydney 2030 plan targets a 70 per cent reduction of greenhouse gas emission compared to 2006 levels in the city's local government area.

A large part of this reduction is planned to be achieved by building a network of gas burners throughout the city that will simultaneously provide power, heating and cooling to public and private buildings. This approach is known as trigeneration, or trigen.

The gas burners will use natural gas, ultimately taking the city off the coal fired electricity grid. Sometime prior to 2030 the city hopes the trigen system will begin to use biogas generated from processing of municipal waste and the digestion of crop residues.

In April 2012 Sydney Council signed an agreement with Origin Energy's wholly owned subsidiary Cogent to begin building the trigen system. The total cost of this project will be $440 million (in 2010 dollars) by 2030.

Destructive climate change from carbon emissions is one of the major threats facing our planet this century. Sydney's plan for electricity locally generated by burning gas — long considered a low emission fuel — sounds likes a positive step for the council to take.

However, serious questions and concerns have been raised by various environmental groups.

Former US vice president and Nobel Prize winner Al Gore wrote in his recent book that he no longer believes it is wise to first move from coal to gas and then later move from gas to renewable, due to both environmental impacts and cost.

Gore explains that each transition is so expensive it is best to move directly from all polluting fossil fuels to renewables. Moreover, Gore says, "[I]t is increasingly clear that the net effect of shale gas on the environment may ultimately be inconsistent with its use as a bridge fuel."

Experts at Beyond Zero Emissions (BZE) studied the city's plan over a number of months and modelled several comparable schemes. In their October 2012 submission to Sydney Council entitled "Energy efficiency plus renewables can do it better", they pointed out the problems with Sydney's plan and gave alternative solutions. BZE calls trigen "Sydney's white elephant".

The Sydney scheme will promote coal seam gas production (CSG), because the trigen network will result in greater demand for gas in NSW. (We will explore this concern in more detail in a future article, but it is important to recognise that a trigen system run by CSG will reduce or even negate any environmental benefits of Sydney's trigen system.)

The cost of Sydney's scheme is almost impossible to predict. Gas prices are rising very quickly in Australia as the east coast becomes connected to export facilities in Queensland and large volumes of gas are contracted for export.

But won't the trigen system soon be run totally by biogas from our waste and drop residues? BZE's Executive Director Matthew Wright raises several concerns about this scenario. One is Origin Energy's Cogent has a 20 year contract with the City of Sydney. How many years would Cogent contract existing conventional fossil gas supplies before moving to biogas? As Wright points out, Origin is one of the biggest names in coal seam gas.

Jonathan Prendergast of Prendergast Projects, who consulted with the City of Sydney on the trigen project, argues that the biogas age will arrive and Sydney's trigen system will be fine. He uses developments in Denmark to support his position.

However, Wright disagrees. He says that although Denmark has been developing its biogas production for two decades, it has less than 200 biogas plants and these produce a relatively small amount of gas. To supply Sydney's trigen system four times as much biogas will be needed as is produced in Denmark.

BZE argued in its submission to Sydney Council that the money planned for trigen would be better spent on looking to the latest building energy efficiency, upgraded building chillers and development of renewable energy technology. They hoped that trigen will be put on hold while their energy efficiency and renewables alternative is given consideration.

However, Sydney Council appears determined to continue with its 20 year plan.

One of the authors discussed in length the Sydney trigen plans with an expert who worked for a number of years in a government regulatory agency dealing with the electricity industry. He has studied the Sydney scheme in depth. He asked not to be named due to commercial reasons.

He said the economic life of the trigen project will likely be decades, potentially locking Sydney into this project for a very long time. Many things can change during that period. 

New technologies will be developed that could be cleaner and less expensive.  The cost of natural gas is rising, and it could much more expensive in the future in comparison to renewables.  As renewable energies are developed other cities and states will benefit from them while Sydney is tied to fossil fuel. 

In short, he believes residents and businesses in the Sydney local government area might pay a much larger financial price than currently predicted if trigen is used, posing a major financial risk to the City of Sydney and its ratepayers.

In summary, we believe Sydney Council has moved too fast into this project without heeding the advice of other experts and looking at other options to deliver on their ambitious carbon reduction targets while minimising financial risks and prolonging fossil gas use. We hope that other agencies in Australia look more carefully at these other options.

In an article next week we will look more closely at the impact of the City of Sydney's trigen plan on promoting CSG development in NSW and the environmental, health and social issues this may cause.

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Posted Friday, February 8, 2013 - 15:59

This is both an excellent and disturbing article. When I first heard Sydney Council was going to bring in a trigeneration program to help the environment it sounded so positive. But it was very difficult to understand and the Council didn't do enough to educate residents, especially about the costs.

Now it appears Sydney is locked into using fossil fuels for decades rather than making the more sensible transition to renewable energies. Renewable energy is the only way to go.

Was this done so quickly just to make the Council look good? It seems that this is the case. But at what cost to the environment, our health and our rates?

Posted Saturday, February 9, 2013 - 11:48


I doubt that we can trust the City of Sydney. I remember when there were plans to drill for coal seam gas in St Peters, a suburb near to the City, the company planning to drill said the gas was to be used to supply Sydney Council's proposed trigeneration pilot plant.

Fortunately drilling in St Peters was stopped. But I wouldn't be surprised if Sydney doesn't use coal seam gas sourced from other sites.

Why is Sydney Council ignoring renewable sources of electrity if Clover wants to be so green? Did the Greens councillors try to stop this?

Posted Monday, February 11, 2013 - 09:20

This is a useful article in a good cause but has 2 major omissions, making no mention of (1) potentially unacceptable, toxic nitrogen oxides generation in an urban environment from gas burning , and (2) depending upon the rate of gas leakage, gas burning can be dirtier greenhouse gas (GHG)-wise than coal burning.

1. According to E-Instruments , "Combustion Training" (see: http://www.e-inst.com/combustion/nitrogen-oxides-nox ): "Nitrogen Oxides (mainly NO and NO2), or NOx, is the generic term for a group of highly reactive gases, which contain nitrogen and oxygen in various amounts and chemical configurations. Most of the nitrogen oxides are colorless and odorless. However, one very common pollutant, nitrogen dioxide (NO2) along with other particles in the air can often be seen as a reddish-brown layer of smog over many cities or heavily populated areas... When NOx reacts with the oxygen in the air, the result is ground-level ozone. Ground-level ozone has very negative effects on the respiratory system, such as causing lung cancer, and on agricultural production. NOx also reacts to form nitrate particles, and acid aerosols, which all cause respiratory problems. Nitric acid, formed when NOx reacts with water, can cause acid rain and the deterioration of the quality of water. Acidic gases along with airborne particles cause visibility impairment and lower air quality." There are concerns that gas burning for electricity in urban areas will produce NOx exceeding acceptable levels. Thus the DECC interim report states: "In the Sydney CBD and other urban canyons, uncontrolled emission of NOx from cogeneration could exceed health-based goals" (see: http://www.environment.nsw.gov.au/resources/air/inp09124.pdf )

2. Methane (CH4) (about 85% of natural gas) is 105 times worse than CO2 as a greenhouse gas (GHG) on a 20 year time frame and taking aerosol impacts into account. Methane leaks (3.3% in the US based on the latest US EPA data and as high as 7.9% for methane from “fracking” coal seams). Burning both coal and methane generates the GHG CO2 (as well as other pollutants) i.e. neither coal nor natural gas are not clean GHG-wise, they are both dirty. A 2.6 % leakage of CH4 yields the same greenhouse effect as burning the remaining 97.4% CH4. Using this information one can determine that gas burning for electricity can be much dirtier than coal burning greenhouse gas-wise (GHG-wise). While gas burning for power generates twice as much electrical energy per tonne of CO2 produced (MWh/tonne CO2) than coal burning and the health-adverse pollution from gas burning is lower than for coal burning, gas leakage in the system actually means that gas burning for power can be worse GHG-wise than coal burning (see "Gas is not clean energy": https://sites.google.com/site/gasisnotcleanenergy/ ).

It is unfortunate that scientists are sidelined in such discussions (noting that very few institutional scientists are prepared to comment publicly in the first place; see Dr Gideon Polya, “Current academic censorship and self-censorship in Australian universities”, Public University Journal, volume 1, Conference Supplement, “Transforming the Australia University”, Melbourne, 9-10 December 2001: http://pandora.nla.gov.au/pan/57092/20080218-1150/www.publicuni.org/jrnl... ).

Peace is the only way but Silence kills and Silence is complicity.

Councillor Angela
Posted Monday, February 11, 2013 - 12:25

It is very concerning that the City of Sydney is embarking on a scheme without sufficient investigation and information. It appears that this is a perfect opportunity for Council to hasten slowly, do proper due diligence and make an informed decision based on independent evidence. Everyone knows that we need to plan for the future, but it is more important to plan well. Councillor Angela Vithoulkas, City of Sydney.

Posted Monday, February 11, 2013 - 14:33

I was wondering what City of Sydney Councillors thought about such an expensive and potentially environmental destructive project. So many thanks for this, Cr Vithoulkas.

Where are all the other councillors? Why aren't they raising questions? Why aren't they and Council staff communicating with us?

And the Greens? They should be jumping up and down since they supposedly are very concerned about the environment and the health of residents. Their silence is most disturbing.

Justin Field
Posted Monday, February 11, 2013 - 15:38

Thanks DrGideonPolya,

The article wasn't meant to be an exhaustive critique of the project and you raise some very important further issues. Methane leakage is raised in today's article which questions whether or not a biogas transition is even possible. If not, the reality in my opinion is that the project will increase demand for coal seam gas development. That would not be a good thing from what we know about the health, environment, water and on farm impacts from that industry: http://newmatilda.com/2013/02/11/can-sydney-green-grid


Posted Wednesday, February 13, 2013 - 14:45

Jon Walter
The authors of this article claim the City’s trigeneraton network would drive up demand for natural gas and lead to increased demand for coal seam gas.

This is nonsense. Even at its full capacity in 2030, the City’s trigeneration network would only account for 3 per cent of projected demand for gas in NSW, or 1 per cent in the Eastern Gas Market, covering Qld, NSW, Vic and S.A by 2030. Regardless of whether this trigneration project went ahead or not, there would still be large-scale industrial, commercial and residential demand for gas.

The authors also question the City’s strategy to move from natural gas for its trigeneration network, to renewable fuels or biogases produced from garbage, sewage, crop and livestock wastes. This practise is happening widely in Europe, led by Germany, Austria, Denmark, Netherlands, Sweden and the UK. Even the National Grid in the USA is developing a renewable gas grid injection program in Massachusetts, New Hampshire, New York and Rhode Island.
For full details see this article: http://newmatilda.com/2013/02/13/city-sydney-defends-trigen-scheme

Posted Thursday, February 14, 2013 - 00:38

People advocating the coal stream gas programs should read about the results from them in USA!

Posted Monday, February 18, 2013 - 12:08

I started to write a reply to the nonsense Jon Walter wrote about the Sydney Council's trigeneration scheme with a link to Allan Jones article, then I read the excellent post on Jones' article by someone using the name GreensGood. That person's post was so good, I'm copying it here for you to read Mr Walter.

"City of Sydney really doesn’t do a good job of defending itself with this santimonious reply. They have done some really good things to green the city, but this project isn’t looking all that green. It sounds like a plan hatched with the gas companies to get the city hooked on another greenhouse intensive energy system.

Using biogas is a great idea, Sydney Water already collects it to power a number of their waste plants but finding a source to power large chunks of the city ? If there is a genuine source of biomass wouldn’t it be more likely turned into gas at the source (say, at the piggery) and then into electricity pumped into the grid ? That seems to me to be a more likely outcome and it exposes council’s plan as a fossil fuel play.

If they’re so keen on this strategy lets see concrete plans for the biogas before committing $’s to the infrastructure."