DON AITKIN |
‘But wouldn’t it be useful to move to alternative energy anyway?’ #9 My perspective on climate change
Posted: 13 Apr 2016 01:58 PM PDT
The quotation in the title of this essay comes from something I noted down in 2010. It was part of a comment somewhere, and it carried the implication that even if you didn’t think AGW was a real problem there were good reasons to go down the alternative energy path. Why was alternative energy a good thing? Well, it was said to be ‘free’, would continue forever, and didn’t require the use of fossil fuels, which were not sustainable even if they weren’t bad for the planet.
I had a particular interest in solar energy, because the Australian Research Grants Committee (ARGC) had pushed considerable funding into a group at the University of New South Wales who were improving the efficiency of solar panels. I had used solar heating panels in the early 1980s to warm a swimming pool, and they were quite effective at that task. But these new solar cells were something else again, able to capture 40 per cent of the sun’s energy, which could then turned into electricity. I needed some ‘priorities’ to persuade government that the ARGC and later the Australian Research Council (ARC) should have more money, and solar energy was one of them.
I’m sure I added at the time that Australia was one of the countries that could benefit most from solar power, given the abundance of sunlight everywhere, especially in the inland areas. That was an argument that had some weight at the time. Most readers will know that the efficiency of the panels has improved since then, and that their price has also come down. Doesn’t that mean that the future is really going to be one of solar energy?
My answer is — at least at the moment — maybe, perhaps in the long run, but not in the foreseeable future. The two problems with solar power are storing it for later use, and garnering enough of it to make an appreciable difference to the needs of the electricity grid for constant and reliable electricity. If the whole world were to be powered by solar energy (assuming some kind of superior storage for evenings and cloudy days) you would need 500,000 square km of land devoted simply to the panels — an area the size of Spain. And you’d need more to provide the interconnections. Until these two problems are solved, solar energy will only be a small part of national grid systems.
In 2014, thirty years after solar cells had become practicable, the sources of electricity for the eastern Australian grid were: coal 73 per cent, natural gas 13 per cent, hydro 7 per cent, wind 4 per cent, rooftop solar 2 per cent and biomass 1 per cent). The rooftop solar panels wouldn’t be there at all were it not for substantial and continuing subsidies for their installation, and they are not suitable for every dwelling. In any case, the commercial and industrial uses of electricity outweigh those of domestic origin.
You will read from time to time how there are provinces in Germany that get 50 per cent of their power from alternative sources, and that on one day South Australia, which has little coal, managed to get an equivalent fraction of its power from alternative sources (wind and solar). In my judgment these results come from seeing what is happening through rose-tinted spectacles. In 2014 the whole alternative sector contributed just 30 per cent of Germany’s electricity needs, and 11 per cent of total energy needs. What is more, solar energy collection has probably reached a peak in Germany, whose power needs are greatest in winter, when the availability of solar power is at its lowest. In South Australia, the nearest supply of electricity from outside the State is Victoria, and there the source is the brown-coal power stations east of Melbourne. Brown coal is indeed the dirtiest of coals; it is used in Germany, too, because that is the chief coal available there.
It is not coincidental that after Denmark (which tries to rely on wind), Germany has the highest electricity prices in Europe, and that South Australia has the highest electricity prices in Australia. The aim of the subsidies to alternative energy is first to improve the efficiency of solar and wind as contributors to the grid, and eventually to make them competitive with fossil-fuel generation, so that coal will no longer be used to generate electricity. Why would we want to do that? Well, that is the AGW orthodoxy: if coal-fired power stations are closed, then there will be fewer greenhouse gas emissions and the planet will be saved. The earlier essays in this series suggest that the AGW scare has little validity, that coal is a useful and relatively cheap source of electricity, while burning it increases the amount of atmospheric carbon dioxide, which all plants depend on for their food.
The ACT Government has spent a lot of money and effort on trying to make the national capital ‘carbon free’, at least in its use of electricity. To study what is being done there is to be embarrassed at the empty showmanship of what is nothing more than a political initiative, whose aim is to convince Canberra voters that they are doing something really worthwhile with their high electricity prices. In fact, all the ACT Government is doing is to increase the number of solar and wind-powered sources to a point where their total output would be something equivalent to the total electricity demand within the the national capital. But anyone who flicks a switch within Canberra will find that her power is still coming from the grid, at the ratio set out above, with coal leading the way at 73 per cent.
While I have some leaning toward solar power, and would be perfectly happy for much more public funding of solar R&D (without subsidies for roof-top installation), I have virtually none for wind turbines, unless you are a long way away from the grid and there is some useful wind much of the time. Both solar and wind are intermittent, which means that something else has to be available as a back-up all the time. Electricity grids are there to provide just the right amount of electricity all the time as needs change. In winter where I live there is a sudden surge in demand for power around 5 pm, when it gets dark and a couple of hundred thousand households go into evening-meal mode. Grid operators know this, and are ready for it. In most Western grids, the back-up is a gas turbine, which can start producing power almost at once. The gas, of course, is a fossil fuel, a form of methane, which AGW scary people like to point to as the real devil. The need for back-up means that it would simply be impossible, with current knowledge, to have any large system solely powered by wind and solar. And the higher the proportion of alternative energy in the grid, the greater the need for greater back-up. It is a real, and at present quite unsolvable, problem.
Wind turbines have almost everything going against them. They are expensive, the CO2 already generated in making them is enormous, they require rare earth minerals which are in short supply, they kill birds, some people living near them hate the sounds they make, and no one would want one across the road. Their value in the grid is always grossly overstated by those who operate them or want to put them in. You will hear that a particular turbine installation will power 45,000 households. And it would, if it ran all the time at optimum speed. The real value is usually a quarter to a fifth of that stated. In my judgment, they are a waste of time, energy and money, and should be dismantled.
I could say all the above without reference to the positive value of carbon dioxide and the weakness of the AGW scare case. The world is not short of coal, natural gas or oil. But once governments start down a particular road, with goals, regulations and subsidies, it is very difficult for them to stop and change course. So many promises and quasi-promises have been made; so many companies have started up on the expectation that these conditions will continue forever; so many public servants have been employed to regulate the system; and so on. And of course such a large proportion of the electorate has been persuaded that all this is not only good for the planet, but effective and efficient as well.
It is none of those things.
Next: But aren’t 97 per cent of climate scientists sure that humans are causing global warming?
Further reading: There is a lot of useful stuff on the Internet, usually by engineers. You will also find lots of pro-alterntive-energy stuff, usually by people who want to sell you something, or industrial associations with the same intent. It is another of those matters that really hasn’t changed in the last few years, save that governments everywhere seem to be backing away from more subsidies. I have written a lot myself, which you can consult by going to the magnifying glass icon on the top right 0f the screen’s home page, and typing in ‘solar’ or ‘wind turbines’, or whatever you wish.
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