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Olives, the universe and everything

as seen from from the Hunter Valley


If only there was a free, in-exhausible supply of energy somewhere that we can use?

Well, the sun, the wind and the waves look like a pretty good option, so why dig coal out of the ground, grind it up, wash it to remove the unwanted rock, load it onto a train, drive it 100km to the coast, load it onto a ship, sail it round the world (burning oil as you do so) then unload it, load it onto another train, drive it to a power station and use it to heat water to make steam to drive a turbine to make electricity.

Is this really the best option in the 21st Century? It might have been an attractive option in 1870 so Sherlock Holmes didn't have to use a gas light to solve his cases, but haven't we moved on?

Pumped Hydro is one of the solutions available

I am by no means an expert in this field, but there are very few people in Australia than can claim to have much in the way of practical experience in this relatively new technology. The concept is simple – find two mining voids that are relatively close together, preferably one at a different elevation to the other. The Hunter Valley should have plenty of this sort of thing – I don’t know how many mining voids are out there but I would guess at dozens. The next two requirements are also pretty straight forward – abundant sunshine / wind to generate renewable power, and access to an electricity distribution grid. Again the Hunter has both of those.

One of the major arguments against solar powered electricity generation is that it only works during the day, and that wind power only works when the wind is blowing. The peak demand for electricity is not during the day while the sun is shining, but in the evening as the sun goes down. The challenge is to be able to store electricity for use later in the evening when the peak is highest. This is exactly what pumped hydro will deliver. The solar / wind generators can also feed the Grid if required.
The infrastructure of pumped hydro requires two large holes in the ground, a solar array or wind farm to generate electricity, a pipeline from one void to the other, and a pump to move water from the lower dam to the dam at a higher location. This pump is driven by the solar / wind power generated by the solar array or wind farm, so moving water from one location to another does not require buying electricity. The concept is to be able to store water in the higher elevation dam until there is a peak demand, then to run water down from top dam to bottom dam through a turbine to generate electricity. No water is lost as it can simply be pumped back – driven by solar / wind – the following day.

The technology behind pumped hydro is not new — a facility was opened in the 1970s at the Tumut 3 Power Station at Talbingo in New South Wales. Pumped hydro is also widespread in Europe, especially in the alpine parts of Italy, Germany and France, and in Scandinavian countries like Norway. It is also widely used in Japan and the United States. The former Kidson Gold Mine site inland from Townsville in Queensland is already operating a 250MW generator this way, with an upgrade to 2,000MW currently underway. By comparison, Liddell Power Station has 4 x 500MW generators so can also generate 2000MW. Liddell releases 14.7 million tonnes of greenhouse gases a year, a pumped hydro scheme of the same size would generate none at all.

The chance of any business wanting to outlay the sort of funds required to build a new coal-fired power station in NSW is negligible, but the current Government does not have much in the way of incentives to business to build this sort of pollution-free generating plant, however. I do wonder if mine owners might see this as a practical way of using the land they have destroyed for farming and have a moral obligation to do something about, something would generate an income from the degraded land.