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Colin Dunstan

Tuesday, 18th March 2008 1.

Mr Wes Stein CSIRO National Solar Energy Centre P.O. Box 330 Newcastle NSW 2300 Email:wes.stein@csiro.au

2.

Mr Bill Bultitude, Executive Director Developments Snowy Mountains Engineering Corporation 220-226 Sharp Street Cooma, NSW 2630 Email: bill.bultitude@smec.com.au

3.

Mr Mick Gentleman MLA ACT Legislative Assembly GPO Box 1020 Canberra ACT 2601 Email: gentleman@parliament.act.gov.au

4.

Senator the Hon. Penny Wong Minister for Climate Change and Water c/- Black Rod's Office Parliament House Canberra ACT 2600

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The Hon. Peter Garrett AM MP Minister for the Environment, Heritage and the Arts PO Box 6022 House of Representatives Parliament House Canberra ACT 2600 E-mail: Peter.Garrett.MP@aph.gov.au

Dear Sirs and Madam, The attached information may be of some benefit. Further information is in a number of documents accessible at “www.issuu.com/colingd”.

For those who believe renewable energy is good, and other energy sources are bad There are two kinds of dogma – those that categorise all things into either one of two pigeon-holes, and those that don't ... If you consistently ask the wrong questions, you shouldn't be surprised when you consistently get the wrong answers ...


Renewable Energy Good Renewable Energy, Bad Renewable Energy Not every form of renewable energy is sensible. Three examples growing in popularity are quite destructive: 1. Ethanol from sugar cane grown in vast plantations in Brazil – on land formerly part of the Amazon Rainforest. 2. “Bio-diesel” from palm oil plantations grown on land formerly part of Indonesian rainforests. 3. Ethanol from maize grown in the United States – on land formerly used for food crops. Renewable Energy Model 1 A renewable energy system might be envisaged that relies upon photosynthesis for the step that recycles carbon dioxide: Forest plantations could be used to embody solar energy into some other substance Inputs: Arable land, water, carbon dioxide and solar energy. Outputs: Fire-wood and oxygen. An existing thermal power station could be used to convert the solar energy harvested from the forest plantation into electricity Inputs: Fire-wood and oxygen. Outputs: Carbon dioxide, “waste” heat and electrical energy.

Many variations of this model are possible: The crop grown can be varied. The substance produced by the crop can undergo various processing steps such as conversion to ethanol before final use, and the end-use can be varied. For example, if ethanol is the end-product, then it might be used as fuel in a car engine. In every case, arable land and water resources have to be allocated to the energy processing cycle – and this means they are removed from alternate uses, such as growing food, or supporting native species in national parks. The overall efficiency of the process can be estimated and expressed on a per hectare basis. The expected value of the energy produced per hectare can also be estimated. The economic and environmental impact of re-allocating arable land and water resources to energy production can also be estimated. These estimates for efficiency, value and adverse impacts can then be compared with several alternate technology-based models that convert solar energy directly into electricity without the use of biological intermediaries and that may not incorporate carbon dioxide in the energy processing cycle. Examples of these technology-based models include solar photo voltaic panels and turbines driven by solar thermal energy.

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Renewable Energy Model 2 A slightly different renewable energy system might be envisaged that relies upon methaneproducing (methanogenic) bacteria for the step that recycles carbon dioxide: Bio-digestors could be used to convert solar energy embodied in waste organic material into methane Inputs: Waste organic material and carbon dioxide (from a steam/methane reforming plant – see next step). Outputs: Water and methane. A steam/methane reforming plant operated with solar thermal energy could be used to convert methane and water into hydrogen and carbon dioxide Inputs: Water, methane and solar thermal energy. Outputs: Carbon dioxide (recycled to bio-digestor – see above step) and hydrogen. An existing thermal power station could be used to convert the solar energy embodied in the hydrogen into electricity Inputs: Hydrogen and oxygen. Outputs: Water, “waste” heat and electrical energy.

Each of the above processes can be designed, costed and implemented by existing manufacturers. As far as I am aware only the combined use of these technologies in a single installation is new: CSIRO Solar thermal energy project at Newcastle, NSW. Currently reforms methane and water to hydrogen and carbon monoxide. (First stage of a steam/methane reforming plant.) No arable land or potable water resources are needed. A solar thermal array would operate even if situated in a desert. Snowy Mountains Engineering Corporation Designed and implemented a bio-digestor and electricity generating plant at Corowa, NSW. Bacteria convert organic waste from a large scale commercial pig farm into methane, which is used as fuel for electricity generation. One possible example for such a processing cycle – Build an installation on an available site somewhere along the route of an existing sewer trunk pipeline. Divert waste from the sewer through bio-digestors and then return the residue waste back into the sewer. Methane produced by the bio-digesters for steam reforming could be supplemented with methane from natural gas or coal-seam gas. Waste heat from electricity generation may accelerate the bio-digestor process, and add to the energy content of the methane produced. That is, the bacteria may use low-grade thermal energy to convert carbon dioxide into methane, like the CSIRO process that uses solar energy to convert methane into hydrogen – each of these two processes embodying thermal energy in the fuel that is supplied to the electricity generators. Carbon dioxide emissions are zero. If I can be of any further assistance, or if you wish to discuss any of the matters raised above, I may be contacted by telephone or email: Telephone: Email Yours sincerely, [C. Dunstan]

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Some References: 1. EXPOSURE DRAFT Mr Mick Gentleman (Prepared by Parliamentary Counsel’s Office)

Electricity Feed-in (Solar Premium) Bill 2007 ... Dictionary ... renewable energy source means any of the following: (a) solar; (b) wind; (c) any other source prescribed by regulation. (From: "www.legassembly.act.gov.au") 2.

Advanced Resources International, Inc: Methanogenic Conversion of CO2 into Methane (METCON) ... Under the U.S. Department of Energy’s Small Business Innovation Research (SBIR) program, Advanced Resources is investigating the feasibility of using methanogenic bacteria, which are known to naturally convert CO2 into CH4, to both help mitigate carbon emissions and provide a new source of gas supply. In Phase I of the project, the six most promising methanogen consortia were identified, as were the mechanisms by which they convert CO2 into CH4, and the general physicochemical conditions needed to sustain this conversion. (From: "www.adv-res.com/Research.asp")

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HYDROGEN FACT SHEET Hydrogen Production – Steam Methane Reforming (SMR) ... The sustainable energy supply system of the future features electricity and hydrogen as the dominant energy carriers. Hydrogen would be produced from a very diverse base of primary energy feedstocks using the resources and processes that are most economical or consciously preferred. Methods to produce hydrogen from natural gas are well developed and account for over 95% of all hydrogen produced in the U.S. and 48% globally. It is anticipated that hydrogen from natural gas can serve as a foundation to the U.S. transition to a hydrogen energy economy. (From: “www.getenergysmart.org” see www.getenergysmart.org/Files/HydrogenEducation/ 6HydrogenProductionSteamMethaneReforming.pdf)

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Energy Supply Systems  

Loss of arable land to renewable energy production - at what cost?

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