subject: Flannery backs geothermal energy posted: Fri, 09 Feb 2007 19:08:51 -0000
[See also http://en.wikipedia.org/wiki/Geothermal_power ... in
California they use sewage to supplement their water input! And,
this kind of generation facility can be used to desalinate sea water.
So it can produce clean electricity AND water - it's a winner!
Check out the "'Delta T', a closed air loop, atmospheric pressure,
evaporation condensation loop geothermally powered desalination
device" - lol - Stu]
Flannery backs geothermal energy
PM - Friday, 9 February , 2007 18:22:00
Reporter: Nance Haxton
MARK COLVIN: The Australian of the Year, Tim Flannery, has made
headlines with his calls to end coal mining and exports, but there's
been less attention on the technology that he says could replace it.
It's geothermal energy, which would convert heat buried deep beneath
the earth into electricity.
Proponents of geothermal energy say it's the only known renewable
energy source that is able to carry large base loads, potentially
providing a constant source of power.
But, it's still years away from providing a viable electricity
supply, as Nance Haxton reports.
NANCE HAXTON: Geothermal energy is still in it's infancy in
Australia, with experimental sites in South Australia, Queensland,
New South Wales and Victoria, but none as yet connected to
Australia's electricity grid.
One of the industry's greatest proponents is Australian of the Year,
Dr Tim Flannery, who told ABC's Lateline program that the electricity
source is one of Australia's most reliable options for reducing
carbon emissions.
TIM FLANNERY: There are hot rocks in South Australia that potentially
have enough embedded energy in them to run the Australian economy for
the best part of a century.
Now, they're not being fully exploited yet but the technology to
extract that energy and turn it into electricity is relatively
straightforward.
NANCE HAXTON: Geothermal energy in Australia is created by drilling
wells underground, some up to four kilometres deep, and then pumping
water onto the hot granite rocks below to generate steam that powers
turbines.
The Energy Supply Association of Australia represents the nation's
electricity generators.
Its chief executive, Brad Page, believes geothermal power will almost
certainly be a significant source of Australia's energy needs in the
near future.
BRAD PAGE: We foresee it in 2030 potentially providing up to seven or
eight per cent of our total electricity needs, which is actually
quite a very large amount.
It's got some challenges, most of where hot dry rocks exist are in
the middle of the country and of course electricity demand is more
around the coast.
So, there are some locational challenges, but we're confident that it
actually will make quite a contribution.
NANCE HAXTON: So this isn't just seen as a green option?
BRAD PAGE: No, no, far from it. I mean, all technologies are going to
be needed to address climate change and provide electricity.
Geothermal is one of the few technologies that offers us 24-hour
seven days a week electricity with no emissions.
NANCE HAXTON: Environmentalists laud geothermal energy's green
benefits, but even they admit that the process has its limitations.
Getting geothermal energy out of the ground requires water to be
pumped in; something that Australia has in increasingly small supply.
Australian Conservation Foundation climate change campaigner Tony
Mohr.
TONY MOHR: We would expect to see that. Any steam that's created
through the process is captured again and reused, so that there's
very little loss of water through the process.
If there are proposals that come through that have a high water
demand, we would expect them to see them go through the same
environmental impact assessment as any other generation plant.
NANCE HAXTON: But Mr Mohr says geothermal energy is a realistic
alternative source of power.
TONY MOHR: Certainly one of the benefits of geothermal energy is you
get a nice, steady supply of electricity and it's independent of the
weather.
So, that really means that it looks a lot like existing coal-fired
base load electricity generation and that is something that we do
need in our electricity grid.
NANCE HAXTON: Origin Energy has traditionally invested in gas-fired
power generation.
But the company's government affairs manager, Tony Wood, says they
have now started investing in geothermal energy options, mainly
because of its lack of carbon emissions.
TONY WOOD: Absolutely, there's no doubt if it wasn't for that then
people wouldn't be pursuing these very technologies because in
absence of the greenhouse issue then you'd be looking to go down the
route of what's the lowest cost power generation and certainly we
expect that geothermal will be more expensive than most of the
existing technologies that are in relation to brown coal for example.
NANCE HAXTON: Dr Iain MacGill from the University of New South Wales
Centre for Energy and Environmental Markets, says much more research
into the geothermal energy process is needed before it can become a
viable power supply source.
IAIN MACGILL: Like many promising technologies they're not yet proven
in a commercial sense.
NANCE HAXTON: How likely do you think it could be that geothermal
power could be harnessed in Australia in this way using hot rocks?
IAIN MACGILL: I think the technology does look promising, it
certainly does.
However that's no guarantee of success, and so what we need to do in
terms of energy and climate policy is as always, you know, it's a
risk management exercise.
We can't, you know, put all of our sort of eggs in one basket which
hasn't yet sort of been proven. And so, it's one of a range of
promising technologies that we should be exploring.
MARK COLVIN: University of New South Wales energy expert, Iain
MacGill, speaking to Nance Haxton.
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