Slashdot Mirror
Iceland Seeking 'Supercritical Steam' For Power Source (bbc.com)
New submitter FatdogHaiku writes: Already getting over 25% of its electrical power from geothermal sources, Iceland hopes to break new ground using "supercritical steam" from a 5 km deep borehole. Is it just me, or does this sound like the start of a movie where everything that can go wrong does in fact go wrong? It's not like they are new to the tech, but working with geologic sources at 450C to ~600C is a new ball game for anyone. It should be noted that Iceland also uses direct geothermal for most of its space heating. "In this area at Reykjanes, we typically drill to 2km or 3km depth to harness the steam, to run power plants and produce clean, renewable electricity," explained Asgeir Margeirsson, CEO of the Iceland Deep Drilling Project (IDDP). "We want to see if the resources go deeper than that." The "supercritical steam" holds more energy than a liquid or a gas. The team wants to bring it up to the surface to convert into electricity, as they believe it could produce up to 10 times as much energy as the steam from conventional geothermal wells.
'Muricans are anti-science idiots who deny the existence of volcanoes, which is why they don't live directly on top of one that can supply them with heat and lava.
I personally blame Trump's racist wall for keeping out the undocument volcanoes.
AntiFA: An abbreviation for Anti First Amendment.
About the worst case scenario is they waste a lot of money for nothing. It's not like they're going to release some prehistoric mutant monster, or hit a pocket of zombie creating virus, or melt down or anything like that.
Why deal with the middle man?
Why do people insist on calling those thing renewable? How exactly do you renew sun or earh?
what kind of pipe they use for this kinda thing, im thinking some kind of ceramic metal hybrid?? Temps and sulfer corrosion must be a major PITA to deal with.
If the drill does hit magma, because it is under pressure, it would be likely to come to the surface rapidly, he explained. "It would come out rather like lancing a boil or popping a spot. It would cause huge problems for the drilling operation itself, but it is unlikely to cause anything more significant than that."
Would not want to be on that drill crew. Falling into lava or getting splashed with lava is just about the worst way I can imagine to die.
" Is it just me, or does this sound like the start of a movie where everything that can go wrong does in fact go wrong? "
Yeah, it's just you.
Or not.
"supercritical steam" just means steam at above the boiling point of water at whatever pressure applies. More specific heat than "saturated steam" (steam at the boiling point of water at the applicable pressure), but otherwise pretty much the same as any other steam....
"I do not agree with what you say, but I will defend to the death your right to say it"
http://www.imdb.com/title/tt0059065/
Have they done anything to address the issue of the earthquakes this can produce? Earthquakes (especially large numbers of microearthquakes) are why geothermal energy is off the table because it damages all of your buildings and infrastructure. To make things worse, the effects of lots of earthquakes on wildlife isn't well understood.
Anons need not reply. Questions end with a question mark.
If a fluid is supercritical it does not have a distinct phase. Steam is vapor phase. You can either have supercritical water, or you can have water vapor. If you have one, you do not have the other.
Most power plants (natural gas, oil or coal) run on supercritical steam anyways, at least in their designed power level. The technology is neither new nor rare. The need to run on "dry" steam for efficiency is known at least from steam locomotives. The only modern power-generating subcritical steam systems I know of are some nuclear power plants where the reactor expects some of the cooling water in it to stay liquid (read: dense) because it serves as neutron moderator as well.
Iceland should stick with regular steam and not use Supercritical steam.
Nobody likes a nag.
>It should be noted that Iceland also uses direct geothermal
It still can't beat nuclear district heating and having your tap water coming out of reactor cooling circuit (Bilibino)
No, not this case. It's not the US we are talking about
why does he have this sort of defeatist attitude, like he wants Iceland to stop researching this? Does he also go on to other areas of energy production and suggest that everything can go wrong, and it's a bad idea to research?
Did you know your decaf latte probably used supercritical CO2 to decaffeinate the beans? Supercritical CO2, also at very high pressures, is a very good solvent and used in many industries.
Have some fun videos about the latter.
https://www.youtube.com/watch?...
https://www.youtube.com/watch?v=-gCTKteN5Y4
Silence is a state of mime.
"In this area at Reykjanes, we typically drill to 2km or 3km depth to harness the steam, to run power plants and produce clean, renewable electricity,"
It may be clean but it is NOT renewable. Unless they're reheating back the magma with solar panels.
Or not.
"supercritical steam" just means steam at above the boiling point of water at whatever pressure applies. More specific heat than "saturated steam" (steam at the boiling point of water at the applicable pressure), but otherwise pretty much the same as any other steam....
That would be superheated steam as opposed to saturated steam. Supercritical steam would be steam that is at pressure higher than water can exist as a vapor and temperature higher than water can exist as a liquid. For water this is above 3200 psia and above 705F.
Tapping geothermal energy is a great idea, but it's not precisely renewable.
The process, whether using natural (in place) water or by water injection, is removing paleolithic heat from a piece of solidified rock. That rock only has so much heat in it and the process of tapping that heat cools it. There are already geothermal fields in Northern California (The Geysers) that are producing reduced power output due to local cooling.
The upside with deep geothermal is that there is a whole lot of crust to drill into and depleted wells can be deepened. With better grid technology more remote geothermal sources can be tapped including shallow magma.
There is a lot of energy available but technically speaking it is neither infinite nor renewable any more than anthracite coal fields were renewable. At the turn of the 20th century mining companies were looking forward to mining these vast fields of coal forever.
Don't take life too seriously; it isn't permanent.
Why does Iceland always hit the news with this crap? The whole country is about the size of Tombstone Az. Geothermal is a much bigger business elsewhere.
You appear to think that most of the heat at the earth's core is residual, in which case presumably tapping this heat would "let it out" and we would eventually run out. This is not the case. The vast majority of the heat (90% or more) is from the decay of radioactive elements. Thus, the heat is being produced continually and is renewable until the radioactive elements decay (should be a good source of heat for at least a few billion years, probably much more). This means that tapping into the earth's core is not going to ruin the insulation of our crust and cause all the stored up heat to get out, because the core isn't really hot because of residual heat – regardless of what people are taught in grade school.
Saying geothermal heat like this is not renewable is ultimately like saying that hydropower is not renewable because at some point the sun will expand and the earth will get so hot that all the water in all the rivers evaporates – which
Its all fun and games until someone frees the Balrog.
[QUOTE]In this area at Reykjanes, we typically drill to 2km or 3km depth to harness the steam, to run power plants and produce clean, renewable electricity," explained Asgeir Margeirsson, CEO of the Iceland Deep Drilling Project (IDDP).[/QUOTE]
As other posters have noted, this is an oxymoron. To renew the heat that resides in the depths of the Earth, one would have to pump heat, against a gradient, back into the earth.
The other issue is the thermal efficiency the the heat is converted to electricity. Turbines typically harness about 35% of the energy in a coal powered electrical plant, the rest escapes to the atmosphere. That 35% does not include the energy used to extract and transport the coal to the electrical plant.
Picture an unimpressed Balrog chained to a treadmill...
I hear polonium poisoning is pretty slow, unpleasant and untreatable.
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
typically used for industrial processes, but one local example may be the area hospital laundry facility, where they typically run in the 2500-2700 degree range at the boiler.
if this is supposed to be a new economy, how come they still want my old fashioned money?
In real world units around 375 degC and 220 Bar.
"The likes of Facebook and WhatsApp are free to those whose privacy is of zero value."
Then we should do this at Yellowstone. If we harnessed enough energy from there, we might be able to stave off a caldera super event, which is overdue.
Brawndo: It's what plants crave!
Depending on the how much pressure the injection well pump can provide and the geology of the field, supercritical geothermal could be possible. Not common, but possible. Most geothermal wells are under 600F and the steam temperature declines over time. Heat carrying capacity of supercritical steam is not great, however, so this could potentially be very damaging to the geothermal field. It would also wreck havoc on most turbine designs, even ones with superalloy parts and overlays. Unlike most power plant steam, where the water chemistry is very carefully controlled, geothermal steam is quite dirty with sulphur and arsenic compounds and salts. Supercritical or even superheated steam could cause a creep / stress corrosion cracking failure quite quickly.
Even those who arrange and design shrubberies are under considerable economic stress at this period in history.
If my calculations are correct, 5km down is right around where the balrogs live...
Thanks to technologies developed by the petroleum industry for deep drilling through solid rock, it is feasible to find enough heat to run electrical generators in most places of the US. Two boreholes are drilled, high-pressure liquid cracks the hot rock between them, and you have a closed loop that delivers steam or hot-enough water. Can run 24 x 7 x 365, stopped and restarted as needed, and located pretty close to where the power is needed. The mass of rock is immense, so there is little danger of cooling it off prematurely. Closed loop is pollution-free, no waste to store for centuries.
DOE had a significant research program going on, but it has been scaled back. Short-sighted thinking.
But geothermal steam is pretty corrosive for the pipes which carry them. Think of lots of sulphur and other "nice" chemical compounds from the literal burning hell.
Thanks.
CLI paste? paste.pr0.tips!
Also the sun's, though if I recall correctly it's only about half as strong.
More to the point though, even an extraordinarily deep 6km borehole, you'd only be reaching 1/1000th of the way to the Earth's center. We're not appreciably cooling the liquid core, or even the outer semi-liquid mantle, we're just cooling some of the hot spots in the solid crust floating on the surface.
In the extreme long term, or if human energy consumption increased radically, that might indeed be a problem. As it is though, the Earth's core is already cooling at about 100*C per billion years. We could double that and the magnetosphere would still be going strong by the time our slowly heating sun boils off the oceans.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
In real world units around 375 degC and 220 Bar.
That would be 22MPa in the real metric system.
Apocalypse Cancelled, Sorry, No Ticket Refunds
It would be crazy to use the geothermal steam directly and not use a secondary boiler.
Apocalypse Cancelled, Sorry, No Ticket Refunds
It's just you.
You are too stupid to know how stupid you are. Hollywood movies are not documentaries. Most of us have already figured that out.
Let me know when you turn eight years old. Then maybe I'll care.
Nobody who takes anything Hollywood makes seriously should ever be taken seriously.
True, that's why around my place we like to use the hPa, as a number it is identical to the Bar.
"The likes of Facebook and WhatsApp are free to those whose privacy is of zero value."