Australia Pushes Geothermal Energy

_martini_ writes writes to tell us Reuters is reporting that several Australian firms are experimenting with taking geothermal energy mainstream. Geodynamics Ltd. will be making an investment decision on their first geothermal power station in early 2006. From the article: "Mother Nature has been kind to us. Australia could be the world leader within the next couple of years given the geological anomalies present in South Australia," says Peter Reid, chief executive of another explorer, Petratherm Ltd."

Geothermal Is Expensive

[geomon (78680)]

There are several problems that geothermal energy will have to overcome before it can be used for any large-scale power production. First of all, geothermal solutions are terribly corrosive and the pipes are subject to scaling. The maintenance costs associated with keeping the plumbing working are high.

These are just a few of the problems [elsevier.com] associated with geothermal energy: the variable nature of the reservoirs and fluids; the depth, location, orientation, number and type of wells; the type and size of power plant; the method of disposal of the spent geothermal fluid and the need to conform with local environmental regulations.

Re:Geothermal Is Expensive

[by Anonymous Coward]

And it's been studied extensively since the 1970s. this article [oit.edu] has a nice summary of the research to date.

Re:Geothermal Is Expensive

[DodgyGeezer (83311)]

How expensive is that compared with fossil fuels? With those billions of taxpayers dollars are spent providing security to ensure regular delivery of oil from their source. A price not reflected for instance in the prices at the gas pump. Then there is all the pollution that causes things asthma, contributing to medical bills.

Re:Geothermal Is Expensive

[ian_mackereth (889101)]

This is quite different to most geothermal installations, though. Most of them utilise vulcanism, with all the attendant sulfur and such to cause the corrosion and scaling. This scheme is in granite that contains low-level radioactivity and should be relatively clean to pump water through. The basic idea is to force water/steam into one hole to open up some fissures, then pump water through those fissures to generate steam that goes up an outlet pipe to drive a turbine. The water's reclaimed and re-pumped down the feed bore.

Environmental impact should be minimal, and there's hardly any ecosystem there to affect anyway. This region was chosen for the Woomera rocket range for exactly this reason. Australia's about 90% of the area of the continental USA, and much of it looks exactly like this area; arid or semi-arid rocky plains.

There's a transcript of an article with quite some depth (ahem.) here. http://www.abc.net.au/rn/science/ockham/stories/s1 440622.htm [abc.net.au]

Re:Geothermal Is Expensive

[Kelson (129150)]

Whether geothermal energy is worth it depends entirely on the location. IIRC, Iceland does well with it.

How geologically active is Australia? Are there any places where hot springs and the like can be tapped on a large enough scale?

Re:Geothermal Is Expensive

[Timbotronic (717458)]

There needs to be a distinction drawn between regular geothermal power from volcanic areas (such as Iceland, NZ, Yellowstone etc) and hot dry rock geothermal power which is what Geodynamics are pursuing.

HDR Geothermal works by passing water through hot, fractured granite. The granite is hot because of the radioactive decay of trace elements in the granite (too low in concentration for any radioactive waste concerns). A thick layer of sediment above the granite effectively creates a heat blanket, allowing the temperature to build to 200-300 hundred degrees C - ideal for heating water without building up extreme pressure.

I'm not a geologist, but I imagine that problems with pipe scaling would be much lower for HDR geothermal than in regular geothermal power, where you've got a lot of salts, sulphur and all sorts of muddy crap bubbling through. The water in HDR geothermal is kept in a closed loop so there's no waste to dispose of. The heat is extracted via a heat exchanger which boils a more volatile fluid such as ammonia and this fluid is used for the power generation. So you've got no impurities going through your generation facility.

Geodynamics say they have enough heat to power Australia at current levels of consumption for 70 years. Unlike solar or wind, the power is constant and can be ramped up or down at will. I'm surprised this has been off everyone's radar for so long.

Re:Environmental regulations????

[Yartrebo (690383)]

Scaling materials do not harm the environment and generally be disposed of like sand. The corrosive materials are safe to dump in small amounts over the millenia as nature slowly weathers rock formations, but I do think that the liquid would have to be pumped back into the rock formation to avoid contamination. (isn't that what they do already?)

If it's really a problem (probably not), one can always use a closed cycle, which will avoid contamination issues at an increase in cost.

The bigger drawback to geoth

Re:Environmental regulations????

[mwood (25379)]

Some perspectives:

Concentrated hydrochloric acid is natural: your stomach makes some every minute. Uranium is natural: it's dug out of the ground like coal (also natural). Horrific, destroy-all-in-its-path wildfires covering thousands of square km. are natural and have been happening since long before humans came along. Just because it's "natural" doesn't mean it's nice.

Geothermal hot spots will be cooled, not eventually, but *immediately*. By a few degrees within centimeters of the tap, millidegrees

Re:Environmental regulations????

[Kelson (129150)]

The issue with scaling and corrosion isn't that it'll escape and damage the environment -- it's that it'll damage the power plant itself. Most power plants work by burning something to heat water, vaporize it, and use the steam to turn a turbine. At least one form of geothermal power involves plugging pipes into the ground where magma is naturally heating water and vaporizing it. In other words, hot springs. But since it's ground water, it's full of minerals that can cause scaling in the pipes. And sin

Energy creation or energy storage?

[dada21 (163177)]

I was reading on a link from LRC about Nature's Nuclear Reactor [discover.com], so the timing of this /. post comes just as I was thinking about the potential energy inside the ground.

I've ran the numbers for solar cells and windmill generators and can't see the overall savings. Taking into account the manufacturing, installation and maintenance costs, are these techniques better for the environment or any cheaper?

Geothermal seems like it would work well, if you can store the energy or throttle back the generation during lulls in need. The setup costs seem huge and I wonder how often they'll tap out a given dig's heat (if ever).

I think money will be better spent in more efficient storage of energy. Batteries, salts and event heat tanks all interest me. I'm not seeing any long term viability of anything but coal, gasoline and natural gas until the storage exceeds the unit per dollar ratio of the 3 gases mentioned.

Re:Energy creation or energy storage?

[Average_Joe_Sixpack (534373)]

I've ran the numbers for solar cells and windmill generators and can't see the overall savings. Taking into account the manufacturing, installation and maintenance costs, are these techniques better for the environment or any cheaper?

As we slide down the fossil fuel depletion curve, it will take a combination of "green" tech to keep humanity from freezing to death. (ie ... Windmills work in New Jersey, but not in Pennsylvania ... Solar thermal works in Arizona, but not in Minnesota).

Re:Energy creation or energy storage?

[WindBourne (631190)]

First off, the fact that private profitable companies are springing up all over doing wind energies should suggest that your numbers are quite probably incorrect.

But with that said, I do think that govs. should be funding research in storage. [slashdot.org] I think that it is wise to assume that the future will include a greater mix of energy generation. By storing, we can generate at anytime, and then pull when needed.

Re:Energy creation or energy storage?

[nathanh (1214)]

I've ran the numbers for solar cells and windmill generators and can't see the overall savings. Taking into account the manufacturing, installation and maintenance costs, are these techniques better for the environment or any cheaper?

Wind turbines pay for their total life energy cost within the first 9 months. They repay their energy input many dozens of times within their lifetime. The materials are also highly recyclable. Offshore farms are practical in many countries and have minimal impact on the

Big anomaly

[Neo-Rio-101 (700494)]

.... given the geological anomalies present in South Australia

You mean the city of Adelaide?

Re:Big anomaly

[Frogbert (589961)]

Quite frankly I'm surprised there is anything at all in South Australia.

Re:Big anomaly

[The Nine (320384)]

You're thinking of Western Australia. :p I'm still not convinced Perth actually exists. I mean, sure, it's on the maps, but when was the last time you ever heard anything about Perth on the news, or met anybody from Perth, or had Perth's existence validated in any other way?

Re:Big anomaly

[Martin Blank (154261)]

It's like Delaware in the United States. I'm partially convinced that Delaware is a fictitious entity created as a tax haven for large companies.

Re:Big anomaly

[Bad D.N.A. (753582)]

Delaware is more like a tax-free haven for those of us that live near DC. Tax free shopping baby.

Re:Big anomaly

[mgv (198488)]

You're thinking of Western Australia. :p I'm still not convinced Perth actually exists. I mean, sure, it's on the maps, but when was the last time you ever heard anything about Perth on the news, or met anybody from Perth, or had Perth's existence validated in any other way?

Ok, I'll bite. As a card carring born again sand groper I think I have to validate my own existance.

Yes, Perth exists. Deal with it. Its (in my opinion) the best city in Australia, as far as actually being a place to live.

Whilst I know (as I was born in Melboune and went to high school in Sydney) that Western Australia was almost not on the map then, its getting hard to ignore now. It has the strongest economy in the country, just about the lowest unemployment (actually, Canberra is lower due to the large amount of government money there), and a city that has a future that doesn't depend on motor cars [wa.gov.au] or even fossil fuels [wa.gov.au], so we aren't going to waste the economic benefits of having a strong economy.

Anyway, I'm sure I'm over reacting to a humourous statement, but I just had to ...

Michael

Re:Big anomaly

[cheesee (97693)]

I live in Adelaide, I would describe it as more of a biological anomaly than a geological one.

Isn't This Dangerous

[MBCook (132727)]

Is this dangerous? I heard this on the radio today and that was what struck me.

So if we use this to power Australia like they suggest, what are the consequences. That would mean stealing a lot of heat from the Earth that is trapped in these geothermal "deposits" (since it sounds like they found concentrated areas of heat higher up than usual). If we cool those down (which is what will happen when we extract heat from them) then what will happen? Will it effect the ground in any way? I'm thinking of towns where they used to mine salt or coal or something and the ground later started to collapse because the stuff was gone. While they are not removing rock, would removing the heat cause problems later? For example: remove the heat -> things cool down -> rocks contract from cooling -> empty space -> fissues?

Anyone know? I realize this would probably be a long-term problem (not something that would show up for a long time). Would this not be a problem because the ground could slowly adjust as we removed the heat, or would the heat stay high until the last minute then plummet (sorta like batteries do) causing problems?

Re:Isn't This Dangerous

[HotNeedleOfInquiry (598897)]

No. It's not dangerous and it's not new technology. I know firsthand that it is used in California and the Sierra Madres of Mexico. Most of the homes in Klameth Falls, Oregon are heated via geothermal energy. I'm sure it's used in a lot of other places, so I'm a little surprised this is even news. I've not heard of any sort of accident or danger, other than the possible release of poisionous hydrogen sulfide gas, and that only during the exploration stage.

There are issues, but nothin insurmountable.

Re:Isn't This Dangerous

[Marxist Hacker 42 (638312)]

Klamath Falls suffered an earthquake a while back, and there was a theory that *part* of the cause may have been some older wells that didn't reinject.

Re:Isn't This Dangerous

[palndrumm (416336)]

Will it effect the ground in any way?

Not really, no. We're talking about big solid lumps of granite, which at the sort of temperatures they're at to start with won't undergo any significant thermal contraction even if cooled to atmospheric temperature. Plus we're only able to extract a relatively small proportion of the overall amount of heat in these deposits, so the overall temperature of the rock won't change a whole lot.

Re:Isn't This Dangerous

[leathered (780018)]

This is what will will happen:

World turns to geothermal energy. Mankind relieved at being saved from global warming.
As a result, the Earth's core cools and solidifies and the planet's magnetic field breaks down.
All life wiped out by cosmic radiation.

Other than that it's not dangerous at all.

Re:Isn't This Dangerous

[Michael Woodhams (112247)]

It isn't like an oil field where, once it is gone, it is gone. The heat is continuously renewed from the earth's core.

It is a lot like an aquifer - a geothermal field will have a limited capacity. Once too much heat is being tapped from it, it will cool down and all users will get less.

Subsidence can be a problem, as can toxic chemicals which accompany the steam/hot water. See the link in this comment. [slashdot.org].

I'm surprised Australia is looking into this - across the ditch here (NZ), we regard you as geological deadsville. The Newcastle quake was magnitude 5.6, in 1989. Our most recent magnitude 5.6 was a week ago [geonet.org.nz] (and 5 others this year.) (OK, not really a fair comparison, as this recent one was 290km deep, and Oz may have had bigger but less damaging earthquakes since Newcastle.)

Oh, and our largest city contains about 50 vulcanos, most recent eruption about 500 years ago.

Re:Isn't This Dangerous

[StikyPad (445176)]

Uh, I'm pretty sure that the rocks aren't heated from the earth's core, which is a little farther down than 5km from the surface. Radioactive decay is actually the source, and that isn't particularly renewable, unless you know of a way to impregnate the rock with more radioactive material. The article suggests 70 years of use at current comsumption rates. (Get it? Current consumption rates?).

Also the radiation isn't really dangerous since it's just trace amounts; it's just that the heat can't escape so

Re:Isn't This Dangerous

[MBCook (132727)]

I didn't mean cool down the planet's core or anything like that. While that would eventually happen, it would take a LONG time.

But if that heat built up over millions of years, it would be possible to drain in if we take energy out fast enough.

Yellowstone

[WindBourne (631190)]

I wish that they would do more around the yellowstone area. The thing is a super volcano so should have loads of heat easily accessable.

Re:Yellowstone

[mrchaotica (681592)]

I agree, except for the fact that it's also a national park.

Re:Yellowstone

[Bad D.N.A. (753582)]

"I wish that they would do more around the yellowstone area" NO... leave yellowstone alone. And while your there, please catch and release.

Sigh

[WindBourne (631190)]

I have been a hard environmentalists since 1971. In fact, it was a major part of my becoming a libertarian in the 90's. So, you do think that we can not take energy from there without harming the area. Ok. Then lets look at alternatives as well as what has happened over the last 5 years.

1. Oil, coal, NG - These speak for themselves. They are getting expensive and they pollute heavily. Not only are we looking at CO2 pollution leading to global warming, but we are putting in Radioactivity, etc in the air.
2. Nuc

Here on the Ring of Fire...

[Repton (60818)]

I'm sure we can lend them some expertise — NZ's first geothermal plant was commissioned in the '50s...

(apparently, we get 18% [ew.govt.nz] of our primary energy from geothermal sources)

Re:Here on the Ring of Fire...

[afaik_ianal (918433)]

This isn't quite the same kind of power generation. A few people have made similar comments about NZ and the US.

From TFA: "While the United States, the Philippines, Iceland, New Zealand and Japan already produce commercial volumes of geothermal electricity, their system uses naturally occurring steam from underground reservoirs and springs, rather than the renewable dry rock technology the Australians are developing."

Re:Here on the Ring of Fire...

[nathanh (1214)]

I'm sure we can lend them some expertise -- NZ's first geothermal plant was commissioned in the '50s... (apparently, we get 18% of our primary energy from geothermal sources)

NZ has a different area of expertise. NZ has naturally occuring hot water springs. Tapping those is relatively easy. That's why NZ has had geothermal energy for so long. Iceland was in a similar fortunate position and they also have geothermal.

Australia is drier than Oscar Wilde's wit. There are no naturally occuring hot water springs. The technology being researched in Australia is Hot Dry Rock. The rocks are dry and you pump fluids down into the rocks. The water is forced through naturally occuring horizontal fissures in the rocks and collected by a second bore. This only works when there are insulating rocks above, below and around the fissures. Otherwise the fluid disperses and you never collect back enough water to make the system economical.

When it does work it's brilliant. The system powers itself and the only significant issue is dealing with scale buildup on the pipes. The energy output is enormous and the capital investment is modest. A single plant can power a small city with almost no pollution and no (as yet known) environmental impact.

also in small scale

[Keruo (771880)]

Not for generating electricity, but geothermal energy is increasingly popular way to heat residential buildings here.
It's already half cheaper than oil burner heating and as the oil prices climb, geothermal becomes more and more attractive option.

geothermal

[H0D_G (894033)]

geothermal shouldn't steal a noticeable amount of heat- remember, the Earth is VERY big and VERY hot. I'd still prefer it if we went Nuclear. and that smart ass with the Adelaide crack... guess where I'm writing this from?

Re:geothermal

[Belseth (835595)]

Still it's nice to see them finally harnessing all the hot air for power. Shame to see it all go to waste. Adelaide is quite rich in some resources.

Re:geothermal

[Yartrebo (690383)]

Unfortunately, the Earth is a great insulator. Heat from the mantle travels exceeding slowly to the surface. The maximum sustainable power density is many orders (at least three, probably more) of magnitude less than solar power. The unsustainable (deplete once) energy reserve is exceedingly dilute compared to fossil fuels. I haven't had time to do some hard math, but my gut feeling is that drawing out 8GW of heat energy will cool off a lot of rock real fast. (assupmtions are 15% rankine cycle and 12.5% net efficiency and a 1GW plant). How many cubic kilometers of rock can their collection system honestly cover?

Iceland has a much larger (though still finite) sustainable energy density, since it sits on the mid-oceanic rift, so it would be a far better site for a geothermal plant, though I have my doubts that 1GW could be extracted even from that island.

Granite is radioactive.

[TapeCutter (624760)]

Australia does not have any major fault lines, no volcanoes and has some of the oldest (most stable) bedrock on the planet. The heat in the Granite is not from magma, it is from the low level radioactivity in the rock itself. A big enough chunk of granite will get hot all by itself. Check out the CSIRO, they have been working on this kind of "geothermal" for at least 10yrs. Their numbers say that one site with two deep wells (500m apart) would remain hot enough to replace the largest power plant in NSW for 50yrs. Intrestingly the site they got those numbers from was just a few miles from said power station.

The biggest problem in Oz is that coal is not only sprinkled everwhere so as to convieniently fuel our current power stations, it is also a major export. These two things combine to make the coal industry fat, lazy and influential.

World leader?

[Malc (1751)]

After Iceland that is. I would think they are the world leader. They way they're going they'll be able to banish fossil fuels. Well, I suppose fishing boats and aeroplanes might be an exception.

Not the first

[rscoggin (845029)]

What about Iceland? I believe they have an extensive geothermal energy system that provides not only electricity, but also heat for those cold Reykjavik nights ;). So how are the Australian firms making it "main-stream"?

Some more info [rochester.edu]

Say NO to geothermal

[jnadke (907188)]

This is just another attempt at Mother Nature to monopolize the energy market. First coal, then oil, now renewable engeries???

We must rise up to defeat this threat. Say NO to Mother Nature.

Yellowstone Public Utility District

[wardk (3037)]

Yellowstone immediately comes to mind as a geothermal power source. I bet if it destroys the environment, the GOP will be all over this.

Ah, geothermal

[localman (111171)]

I just visited Iceland a couple months back, and I have to say that it made me wonder why geothemal isn't more popular.

My favorite iceland moment: I went to the blue lagoon [geographia.com], which is a spa next to a geothermal powerplant. Basically you've got this cloudy blue mineral water in a huge black volcanic rock basin, at one end you've got the spa, where you get in, and the water is probably just over 80 degrees. Then on the other end of the basin you've got geothermal runoff water boiling in. You can get as close as you like to the inlet, but when you get within 30 feet or so you're nearly getting cooked. There's also some silica mud and waterfalls along the sides. The view is dramatic with the industrial steamstacks on one end, a classy spa structure on the other, and the natural volcanic pool in the middle. Highly recommended.

But the point is: you're bathing in powerplant runoff. And it's supposed to be good for you. Now that's pretty amazing: I want that kind of powerplant in my back yard. And looking up in Wikipedia [wikipedia.org], the largest geothermal installation in the world is actually in California. And it doesn't put out some wussy windmill sized power, we're talking 2000 Megawatts -- that's nuclear plant territory, if I understand correctly.

Reykjavik is reputedly the least polluted city in Europe, and most of the heating and power is provided by geothermal -- they just run hot pipes through the houses. Iceland has some pretty unique geographic properties that lend itself well to the process, but it's hard to believe that this can't be harnessed elsewhere to good effect. I mean, I understand the startup costs are very high. And I understand the technology needs work. But we're talking about a nearly limitless source of energy that is clean, safe, and politically sound. It seems like a pretty wise investment.

Cheers.

Re:Ah, geothermal

[John Nowak (872479)]

But the point is: you're bathing in powerplant runoff.

Big deal. You've been able to do that in New Jersey for decades.

1,200 Megawatts?

[StikyPad (445176)]

There could one day be plants supplying more than 1,000 megawatts of power if the market allowed it, which is theoretically a good chunk of the 1,200 megawatts required to power South Australia.

You mean... 1.2 jigawatts? I'm sorry, but the only thing that can generate 1.21 jigawatts of electricity is a bolt of lightning.

Very Cool Technology

[foo fighter (151863)]

I was just in a small, community bank in the U.S. that installed geothermal HVAC when they rebuilt a decade ago.

They recouped the cost in five years and are very, very happy with the system. It heats for almost no expense in the winter (sometimes they have to fire up the natural gas furnace when it gets way below freezing) and cools for nothing in the summer.

It's also been basically maintenance free. Nothing on the order of what some of the naysayers here would have you believe.

I've also seen several rest stops in the area that use geothermal wells to cool and heat very effectively and efficiently. Near-zero maintenance is a very important thing for rest stops.

From what I've seen, geothermal is underutilized and underhyped and should be investigated closely by anyone doing new construction.

Re:PG&E has been doing this for decades in Cal

[Yartrebo (690383)]

At least they're nice and honest and admit that it's a non-renewable resource. They talk about an estimated reserve of at least 50 years and their depletion rate. They also don't use the word 'sustainable' that many people attach to geothermal energy.

The only thing I would like in addition is what is the production in GW*h/year? They mention peak of 1.1GW, but that implies just a 1.1GW turbine. My guess is that the geothermal energy is easily throttled, so they run it as a peaking plant to get the most bang

Re:I'm a geothermal geek

[Anthony (4077)]

I am studying at the ANU dept of Earth and Marine Sciences that is doing a lot of the research in this. This is not hydrothermal. You are right, there are no active margins and no active hotspots. This is using 3-4km deep drill holes, injecting plentiful artesian water down, fracturing the rock at depth and the heated water returning. The anomaly is a large intrusion that is near enough to the surface to make the project feasible. Sorry I haven't the paper at hand. Look at Geodynamics [geodynamics.com.au] or look for papers by Prame Chopra. The "limited life" they are projecting is 300 years.