The Turnbull Coalition Government in
Canberra and the Hodgman Liberal
Government in Tasmania have laboured to produce two new energy schemes - Snowy 2.0
and the "Battery
of the Nation".
These schemes
are being touted as ‘clean energy’ providing stability across the nation’s
power networks, supply into the future and cheaper consumer costs.
One small
problem……
Both are pumped hydro systems which will actually
use more power than they generate as their electricity consumption will be
high.
That is, the
total megawatts of electricity from other sources required to pump the water into
the hydroelectric plant will exceed the megawatts of electricity produced by
the plant.
Not all
the potential electricity produced by the plant is realised, because pumping
water uphill and, the conversions of the potential energy to kinetic energy to
electricity is less than 100% efficient across each stage of the entire process.
It seems efficiency loss would run somewhere between 20% to 40%.
Then there
are the environmental effects.
Hydropower projects can
reduce the flows in rivers downstream if the upstream flows are trapped behind
a reservoir and/or diverted into canals that take the water off stream to a
generation unit. Lowering the flows in a river can alter water temperatures and
degrade habitat for plants and animals. Less water in the river can also reduce
oxygen levels which damage water quality.
Water is typically
stored behind a dam and released through the turbines when power is needed.
This creates artificial flow patterns in the downstream river that may be very
different from the flow patterns a river would naturally experience. For example,
rivers fed mostly by snowmelt may experience much higher flows in the winter
and spring than the summer and fall. Hydropower operations may differ from
these natural flow patterns, which has implications for downstream riparian and
aquatic species. If water levels downstream of a hydropower project
fluctuate wildly because of generation operations, fish could be stranded in
suddenly shallow waters. If operations cause a more static flow schedule
throughout the year than what the river would normally experience, the movement
of sediment along a river section could be disrupted, reducing habitat for
aquatic species. Fewer seasonal flow events could also cause a riparian
corridor to thicken into a less dynamic channel as saplings that would usually
be seasonally thinned by high flows are able to mature.
Dams can also block the
migration of fish that swim upstream to reach spawning grounds.
In addition, large dams
created in heavily forested areas have been known to produce high levels of
methane into the water and air in the period following construction.
The Snowy
Mountains Scheme already contains one power station which includes capacity for
pumped hydro - Tumut 3 Power Station at
Talbingo Dam. It has a maximum 600 MW capacity and reportedly rarely uses its
pumped hydro due to at least 30% efficiency loss. For every 1MWh of
pumping the amount of generation that results is only 0.7 MWh of electricity. Operating
hours when storage full is 40 hours.
The proposed Snowy 2.0 hydro scheme will have a
maximum 2,000 MW capacity and will run an energy deficit as there will
be an est. 24% difference between the amount of energy required to pump the
water in and turn it into electricity and the amount of electricity the scheme actually
produces. Operating hours when storage full is expected to be up to 7.3 days.
Its pumping storage
is expected to have a life time of 40-60 years and for that the Australian taxpayer
is expected to watch at least $4.5$ billion leave general revenue and go towards
its construction.
It will the
eighth power plant constructed within the Snowy Mountain Scheme.
Snowy 2.0 will
be inserted 1km underground somewhere between Talbingo and Tantangra reservoirs.
Rivers which feed the Snowy Mountain Scheme are the Tumbarumba, Tooma, Tumut, Eucumbene,
Snowy, Jindabyne and Goodradigbee - their flows are expected to
decrease over time due to climate change and, it is predicted that median water runoff
into the scheme will be 13% lower within the next 50 years.
The bottom line is that the entire Snowy Mountains scheme (including 2.0) will very likely be water hungry in the lifetime of today's primary school kids and operating on ageing infrastructure. It is also likely that by that time the amount of electricity it can produce will have fallen.
It is a
continuing marvel that the Howard, Abbott and Turnbull governments all only
seriously considered those energy schemes which are at
the higher end of the negative impact scale.
The 2006 Howard Government's Switkowski report into the feasibility of nuclear power generation is a case in point. Now in approaching a large-scale renewable energy project this current federal government again choses one with a long list of potential negatives.
For the life
of me I cannot see why solar, wind and wave power frightens Liberal and
Nationals MPs and senators so much, when overseas experience shows just how
successfully these can be harnessed by national governments that believe in climate change and the need for mitigation measures.
Reference Material
Snowy 2.0 feasibility
study information and reports:
A short summary booklet
on the feasibility study is available, click
here.
The Marsden Jacob
Associates report (an independent expert economic analysis of the changing
energy market) commissioned as part of the Snowy 2.0 feasibility study is
available, click
here.
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