Carbon Tax tips the scales for Munmorah coal power station closure

Delta Electricity this afternoon announced the closure of the 45 year old Munmorah coal fired power station at least partly due to the introduction of the carbon tax. The power station is located on the shores of Lake Munmorah on the central coast of NSW between Sydney and Newcastle.

Reasons for the closure being cited by Delta Energy include the reduction in energy demand in NSW resulting in an excess in electrictiy supply, the aging nature of the infrastructure and the high cost of maintenance, and that "the carbon tax further erodes its viability."

The local Wyong shire Council and environment activists wanted Munmorah decommissioned due to environmental reasons with any rehabilitation likely to result in 4.2 million tonnes of greenhouse gases a year, according to a report in the Lakes Mail.

Greenpeace activists successfully closed down the power station in November 2007 in protest about the lack of action on climate change mitigation.

The station had been operating in standby mode since 2010, with the last production for the grid in August 2010. Constructed with 4 350MW generators with a total capacity of 1400MW which went into production 1967 to 1969. Two units were decommissioned during the 1990s. Unit 4 last operated in March 2009 and unit 3 operated until August 2010 participating in a pilot carbon capture project.

The staff of 100 that worked Munmorah have been reassigned to work at the Vales Point power station according to Delta’s Chief Executive Greg Everett.

"The process of decommissioning will require staff activity at Munmorah over the coming weeks and we will consult with staff and unions on the structure of the business for the longer term", said Delta CEO Greg Everett.

The Delta Energy media release says that there is development consent for the site to be rehabilitated for coal or gas fired power station but "this would require substantial new capital investment by a future owner."

Delta Energy Carbon Capture and Storage Pilot project

The "clean coal" carbon capture pilot project was established in 2007 with State Government funding of $5million; the first phase of $150 million carbon capture development to be jointly funded by coal companies and the state. The pilot plant was run by Delta Energy and the CSIRO. The pilot plant went into operation in 2009 and used a post combustion ammonia absorption technique to extract the carbon dioxide. As storage was not part of the pilot program the 3000 tonnes captured per year were then released to the atmosphere, according to the zeroco2.no Munmorah project page.

According to Delta Electricity the "pilot plant exceeded its targets for capture rate, carbon dioxide purity and sulphur removal". The NSW Government project website noted that capture rates greater than 90% were achieved with high purity CO2 greater than 98.5% and high sulphur dioxide removal.

The pilot plant was relocated to Vales Point for further research during 2012 for scaling up to a demonstration plant. But a suitable site for geosequestration of the liquid carbon dioxide is still being researched. Stage 1 development is set to start in 2013. CSIRO scientists are heavily involved in researching post combustion capture and underground CO2 storage.

Part of the problem with underground storage - geosequestration - is ensuring the geological seal on the liquid CO2 remains tight. A leak of CO2, even a relatively minor one, would undo all the mitigation action achieved with carbon capture and storage process.

The problem is large scale storage of CO2 in rock formations can contribute to seismic activity which may result in leakage. A new scientific study by Stanford University Earth Science professors Mark D. Zobacka and Steven M. Gorelick argues that large scale geologic storage of carbon dioxide may very well trigger earthquakes. The authors say in the article abstract that carbon capture and storage is far to risky and expensive for use on the scale required for climate mitigation. You can read more on this issue and recent scientific research in my article: Carbon capture and storage and the Melbourne Earthquake.

Another issue with carbon capture and storage retrofitted to coal fired power generators is that they lock-in fossil fuel dependency and addiction to coal. Neil Perry, a senior lecturer at the University of Western Sydney presents this issue - Carbon lock-in: social-technological inertias increasing our addiction to coal-fired energy on the Conversation website.

Clearly weaning ourselves off carbon emissions and coal dependency is going to be painful and involve much more campaigning and pressuring government and businesses to adopt clean energy behaviours. The carbon price scheme implemented on 1 July 2012 and the closure of Munmorah is just a first small step.

Sources

• Delta Energy media release, July 3, 2012 - Munmorah power station to close
• Paul Callaghan, Lakes Mail, 14 July 2011 - Turn off Munmorah call
• Delta Electricity - Carbon capture and storage research. Accessed 3 July 2012
• CSIRO 29 November 2011 - Reducing greenhouse gas emissions through carbon dioxide storage