Antinuclear

Australian news, and some related international items

#ScottyFromMarketing ‘s bushfire inquiry studiously ‘ignores’ carbon emissions

February 12, 2020 - Posted by | ACT, climate change - global warming, politics

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  1. In his address on 12th February 2020 to the National Press Club Australia’s Chief Scientist, Dr Alan Finkel, stated “Climate change is Nature’s reaction to our actions. It is real, and it is already happening with a rapidity that is deeply affecting our way of life.”

    In respect to mitigation, he says “focusing on energy will present us with the best return on investment. But we cannot abruptly cease our use of energy”. This statement is at odds with data presented by Dr Finkel which clearly supports the need for urgent rapid action.

    Dr Finkel’s approach to human-induced climate change is entirely on energy supply. In only one very brief sentence does he mention energy efficiency. No mention is made of reducing energy demand and he leaves no doubt that such an idea is inconceivable. He clearly expects and wants higher energy use as demonstrated when he talks about meeting “the energy needs of the future without sacrificing standards of living, or undermining the economy.” There is no mention of issues such as quality of life or national and international equity. Australia is one of the most affluent countries in the world but Dr Finkel wants more and more. The message appears to be “Greed is good” but what if China and India take the same attitude? China’s per capita greenhouse gas emissions are already half that of Australia’s. If China, and then India, want to increase their emissions through increased use of fossil fuels “to keep up with the Jones’ ” what hope will there be of preventing runaway climate change?

    Dr Finkel’s answer is hydrogen fuel which contributes a negligible amount to global energy supply but which Dr Finkel considers the mitigation hero which will save Australia and the world from catastrophe. The problem is the time scale involved.

    The hydrogen economy is not a new idea, in my lifetime it has been around for over 50 years, during which time many scientists have endeavored without success to find an economically practical efficient way to produce hydrogen from water, including by electrolysis (using electricity) and photolysis (using light).

    The closest that the world has come to widespread use of hydrogen as a fuel is what is commonly know as “town gas” which is produced from coal and contains mostly the chemicals that make up natural gas with a small amount of hydrogen.This gaseous fuel is safe to transport through pipelines in much the same way as is now done for natural gas. Hydrogen is a relatively small molecule and can leak through steel pipes. It is also capable of making steel very brittle (hydrogen embrittlement). High amounts of gaseous hydrogen would require completely different pipes which are not susceptible to very dangerous embrittlement and hydrogen leakage. Containers for storing and transporting hydrogen exist but are not in common usage compared with other fuels

    In promoting hydrogen as the hero of mitigation Dr Finkel is scientifically inaccurate, perhaps in order to simplify the subject for public consumption through the media. His use of the term “split” is reminiscent of his well-known support of nuclear power (splitting the atom).

    In the context of electrolysis liquid water is not split but REDUCED at an electrode catalyst (the cathode) in an electrolysis cell consisting of an ionically conducting medium (electrolyte) between a cathode and an anode. Electrons are transferred from the cathode to dissolved molecules close to the cathode surface in a reaction that involves molecules containing hydrogen ions or atoms, or water molecules, depending on the acidity of the electrolyte. This results in the formation of hydrogen atoms (H) which combine to form hydrogen molecules (H2, commonly simply referred to as hydrogen). The reaction is an electron transfer, followed by a combination which is just the opposite to splitting.

    A major problem with producing hydrogen by either electrolysis or photolysis is finding inexpensive, durable catalysts without which the reactions are energy inefficient. Dr Finkel gives the misleading impression that water contains readily available hydrogen (H2).

    Electrolysis doesn’t appear to be Dr Finkel’s favored option for producing hydrogen “because it will increase the demand for solar and wind electricity”. This seems to run contrary to the prevailing strategy of storing renewable energy during times when there is excess supply for use when demand exceeds supply.

    Dr Finkel strongly supports using the carbon in either coal or in the carbon containing molecules of natural gas to reduce water to hydrogen. Unfortunately this process simultaneously produces the same greenhouse gas, carbon dioxide, that is produced when coal or gas are burnt. Approximately 50% more water as carbon (by weight) is consumed in this process. Strangely, Dr Finkel describes this as the “carbon dioxide being left behind” and involving “little added cost for its extraction”.

    Dr Finklel supports the use of hydrogen for transport because “hydrogen fuel carries much more energy than the equivalent weight of batteries” but conveniently neglects to include the weight of the containers to store the hydrogen. He also omits to mention the relative VOLUMES of hydrogen gas and batteries.

    Dr Finkel’s argument for supporting the use of hydrogen instead of coal to produce iron from iron ores (e.g. iron oxide) is only valid if the hydrogen is produced from renewable sources of electricity such as solar and wind. If the hydrogen is made by reacting coal with water then there is no advantage. The overall reaction is exactly the same.

    Despite supporting the production of hydrogen using coal, Dr Finkel refers to exporting hydrogen in the terms “to ship sunshine “.

    Comment by Dennis Matthews | February 14, 2020 | Reply


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