Parliamentary Committees

PUBLIC WORKS COMMITTEE: BOLIVAR WASTEWATER TREATMENT PLANT

Mrs VLAHOS (Taylor) (11:21): I move:

That the 405^th report of the committee, entitled Bolivar Wastewater Treatment Plant Energy Use Optimisation, be noted.

The Public Works Committee has heard that the optimised energy use of the Bolivar Wastewater Treatment Plant is proposed to alter the current energy supply configuration for that precinct by connecting natural gas to the Bolivar site; converting existing gas turbines to run solely on natural gas; installing new reciprocating engines to create more electricity from the available biogas (digester gas) created as a by-product of the sewage sludge treatment process; providing a chemical dosing plant adjacent to the Bolivar digesters to reduce the formation of hydrogen sulphide in the digester gas; and undertaking necessary electrical modifications to enable connection and synchronisation of the generating plant with the ETSA supply.

The estimated cost of this project is $25.9 million and will result in net annual operating savings of $1.3 million. Additionally, electricity market revenue of $0.7 million per annum will be earned and around $0.9 million worth of additional renewable energy certificates (RECS) will be created each year. The project provides a 25-year net present value improvement over the 'do nothing' base case of $14.2 million. The capital payback is estimated at eight years. The project will also result in significant reduction in greenhouse gas emissions from the Bolivar site, by more than 11,000 tonnes CO₂e per annum.

Specifically, the proposed works in this project comprise: supply and install approximately 6MW of reciprocating engines in the Bolivar powerhouse to run on digester gas supplemented with small amounts of natural gas by economic supply; supply and installation of a ferrous chloride dosing plant located adjacent to the Bolivar digesters; the conversion of the existing turbines to operate on high-pressure natural gas; establishment of high-pressure natural gas supply to the site by the SEAGas pipeline; provision of high and low pressure natural gas metering to the Bolivar powerhouse; supply of natural gas to the reciprocating engines to supply supplementary fuel and existing gas turbines as a primary fuel; and connection of new generating plant output to a value of 11,000 kV switchboard to the powerhouse which will connect to other existing 11kV switchboards in the wastewater treatment plant.

The main orders pursuant to the project are expected to be placed in July 2011, with construction commencing in January 2012 and completion in July 2012. Based on the evidence presented to it, pursuant to section 12C of the Parliamentary Committees Act 1991, the Public Works Committee recommends to the parliament that the public proposed work be put forward.

The Hon. R.B. SUCH (Fisher) (11:24): Many years ago I used to take students on various educational tours and one of them was to Bolivar Wastewater Treatment Plant.

The Hon. A. Koutsantonis: As you do.

The Hon. R.B. SUCH: The minister is talking a load of crap again! Many members may not realise, but for many years at Bolivar they have been generating electricity by the production of gases there. For those who have never been there to look at the facility, I urge you to do so because it is a great example of maximising the benefit from, in this case, waste products providing electricity for the running of the plant.

I know that for years there were problems. ETSA was reluctant to allow any surplus electricity to be put into the main grid, which I think was a bit short-sighted, but members should appreciate that many years ago we had some forward-looking officers within the old E&WS who ensured that it was not just a treatment plant for sewage but it actually generated electricity which then ran the plant itself.

This is an excellent additional initiative. Other countries such as Singapore generate a lot of their electricity from burning rubbish. We may not be quite at the point yet where that is economical, but I think we should be looking at every opportunity to maximise energy production from what is often classified as waste products or waste materials, so I commend SA Water for this. I think it is a fantastic additional initiative to build on the excellent work which has already been done at Bolivar and which has been in operation for many years, producing their own electricity on site.

Motion carried.