Friday, 10 March 2017

Dear Malcolm, About your clean coal........



A letter to Malcolm Turnbull:

Dear Malcolm,

I am a retired power industry engineer with considerable expertise in the asset management, performance and efficiency of coal fired generation and I can assure you emphatically that building a new coal fired power station of any type would be technical and economic insanity. Let me explain why. Capacity Factor is a measure of how much power is actually generated as a percentage of what it could produce if it ran all the time at its nameplate rating. Because of the high capital and fixed costs of coal fired plants you need to achieve a Capacity Factor of more than 85% for all of its 30 year life to be economically viable. Below 70% you lose money and also suffer large efficiency drops and corresponding increases in levels of CO2 and other harmful pollutants. Below 55% the major components of the plant start to fail due to the inevitable increase in thermal cycling of the plants as they ramp up and down or are switched on and off. Do you know the current capacity factor of our existing black coal power stations in the NEM (VIC, NSW, QLD)? I guess no because I had to go through all of the latest annual reports of the generation companies to calculate it. AND IT IS 53%. This is because wind and solar are cheaper (regardless of the RET) and have displaced more expensive coal fired plants in the energy market. (At least we are in front of China where the average CF is 50% for exactly the same reason). So how can we justify a new, very expensive ultra critical coal plant when its power cost will mean it cannot pay for itself, it will not be able to achieve any efficiency improvements or CO2 reductions due to operating at reduced loads and is also likely to have a short life because the exotic metals needed are extremely susceptible to thermal fatigue? You will notice I have not referred to politics or climate change in my discussion, just engineering and economics. I should also point out that it will take ten years to build a new power station and I suspect we don't have that long when we are running our very old power stations with increased thermal cycling. We need to be accelerating storage options, not being distracted by technology that is no longer appropriate to the market.

Wayne Bissett.

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