Wind a weak solution
WITH reference to the letter from Glen White, TB, 26/5.
I have found that people who endorse wind power do not actually know how a wind turbine works.
The rated power generated by a wind turbine is at its maximum when the wind velocity is within a specific range, usually between about 40-90km/h.
Much above that and the unit shuts down to protect itself from mechanical damage.
If the wind speed is half the optimum speed then the output will be one-eighth the rated output.
In the real world the wind turbine will produce its rated supply output for 30-40 per cent of the year and it will be erratic, requiring compensation to match the phase and frequency to the grid system.
This means it has to be supplemented by an alternate supply.
If the turbine stops completely then power from the grid is required to restart the turbine.
You now have the situation where the wind turbine has to be backed up by another source of power to the grid.
Hydro is the best source of backup because it can quickly be brought up to maximum output to compensate for the continuously varying output of the wind turbines.
Australia is not blessed with hydropower capable rivers.
The other power station that can be brought up to maximum quickly is the gas-powered generator.
The problem is that the gaspowered generator is burning gas (fossil fuel) while it is in an idle state waiting to compensate when the wind generation decreases. This also reduces the efficiency of the gas-fired power plant with gas being wasted.
Glen states that Australia’s renewable energy capacity is 26 per cent.
This is an inaccurate claim because the wind generators are only supplying their rated output for less than half the year.
At the present time, for every renewable energy project there must be a fossil fuel or hydro generator ensuring power 24/7/365 to keep us living the lifestyle we have become accustomed to.
If you factor in the need to have 100 per cent backup for any renewable energy in Australia then I cannot see how renewable energy can possibly provide cheaper electricity. I am sorry Glen, global warming or not, if you want to be able to turn your lights on and we don’t go nuclear or learn to harness our geothermal assets you will be stuck with fossil-fuelled power plants for a long time to come.
MERV JOHNSTON, Kirwan.