Friday, June 17, 2016

An open letter to Hydro Tasmania

Dear Hydro-Tasmania management,

You are far more aware than I of the energy crisis in Tasmania, compounded by flooding in June 2016, aggravated by unusually warm water in the Tasman Sea, and possibly worsened by cloud seeding (which was undertake by Hydro despite the flood warning).

I am concerned that there might have been other mismanagement, not only concerning the selling of power to the mainland and possible risk to the integrity of Basslink (see below) but also the selection of reservoirs to disproportionately drain. 

Basslink integrity and turbine safety
In an article in the Saturday paper, called "Tasmania's power crisis" Luke Crowley, spokesman for the union representing high-level hydro workers in Tasmania, Professionals Australia, is reported to have said: "the problem, .. has been coming for a long time and is not just due to lack of rain or the cable break. .. He says switching from such high levels of export back to import put more stress on the cable and, he says, may have contributed to the breakage. He says such profligacy with the hydroelectric resource not only has “fried” the cable but led to levels in the dams that are so low – and have been compounded by the lowest recorded annual rainfall in the past year – that the actual physical infrastructure of the dams themselves is being threatened."

Luke Crowley also warns of "a whirlpool effect where air gets into the turbines due to the low water levels and then gets compressed and expands and explodes. He says engineers are telling him that, with no rain, many of the turbines would be unsafe to operate within two months."

The pattern of reservoir drainage

Despite the recent flooding, some of the biggest reservoirs are still very low. For example, today (June 18, 2016) Great Lake is still 16m below the dam wall, and Lake Gordon is an incredible 40m below its dam. Yet, the levels for the 5 dams on the Mersey Forth are either spilling or almost spilling. In the recent floods water not only spilled over the spillway of the Cethana dam, but I am told, was so high for a while that it almost spilled over the Cethana dam wall.

Since the 5 dams on the Mersey Forth system were all spilling simultaneously should these reservoirs have been drawn down far more than Lake Gordon etc? Flooding of this system significantly harmed the towns of Latrobe and Forth, as you know.

The case for much more prudence in supplying the Australian mainland with hydro power

Of even more significance, my opinion is that Tasmania should be far more frugal exporting its power to the mainland than it has been, even if there was a carbon tax and even if no El NiƱo is forecast. Instead, it should be using its carbon friendly power to attract skilled job-intensive enterprises to the state, similar but more biased to people than to big business, than your old policy of "hydro-industrialisation". 

There is an obvious exception to being frugal with the export of hydro-power. Such power can be safely exported not only if the dams are spilling, but also also if the dams are near full with rain forecast; especially if towns vulnerable to flooding lie downstream.

About the author
I am Australia's first IPCC contributor to have been arrested for civil disobedience concerning climate change (2014). I was also arrested for civil disobedience in 1983 protesting the policies of Hydro Tas, concerning its proposed dam on the Franklin River, following the loss of Lake Pedder. The flaws in your policies were clearly apparent, at that time, on economic grounds apart from anything else.

I have lived in Tasmania, intermittently, since 1974, and I have owned land in the catchment to Lake Cethana since 1978; I still own this.

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