DEAR News Of The Area,

IN News Of The Area on Feb 8 2024 Steven Low quoted some very salient facts in relation to the effectiveness of wind farms.

According to published data I have read the total installed potential capacity of wind farms in Australia is 9.1 GW.

As of at 03:00 this morning wind generated energy was contributing about 3.1 GW of a total demand that peaks at the same time of 19 GW.

At midday today demand was 29 GW of which wind input was 2GW.

Less than seven percent of the installed capacity.

Other renewables were contributing 16 GW (Reference: anero.id).

Steven Low points out offshore wind may be able to generate more than land based wind farms, so the proposed 5 GW system proposed for our coast might be capable of producing more energy than a land based system.

According to the centre for sustainable systems at the University of Michigan the capacity factor of a wind turbine is its average power output divided by its maximum power capacity.

Land based wind generators have an average capacity factor of 35 percent.

Offshore wind is generally stronger and the generator’s capacity factors potentially could reach 60 percent.

The US has a cumulative capacity of 142 GW with more than 72,000 installed wind turbines.

Based on average capacity factors that is an average of approx 50 GW available at any moment in time.

The research paper I have read suggests the maximum efficiency of a wind turbine is 59 percent, also known as the Betz Limit.

Most turbines can only extract 50 percent of the energy that passes through the rotor area.

There are further energy losses through friction and inertia of the gearbox and generator as well, therefore the most one could expect from the Port Stephens project would be less than 3GW.

On purely a cost benefit analysis the capital cost has a service life of 20 years, plus servicing a wind farm 20 kms offshore every six months gives rise to many questions about the viability of such a project.

Regards,
Bruce LUMSDEN,
Pennant Hills/Hawks Nest.