Conventional geothermal is about 4-5 cents/kWh, on par with natural gas in the US. The dominant capital cost is drilling a large well (you need volume), and so geothermal plants are generally only built in areas that require shallow (1km) wells.
Well costs are ~quadratic in depth. Given how much money has already been spent optimizing drilling for the oil&gas industry, along with how cutthroat that market is, I don't see the cost coming down significantly. As a result, deep geothermal will likely be limited to niche regions like Iceland. And you need deep geothermal to scale it past the existing locations.
I would love to be wrong, since geothermal checks all the boxes for renewables and is also suitable for base load power, but I don't see an obvious path forward short of a drilling tech miracle.
Don't bill deep geothermal as any sort of green. There are usually emissions that have health consequences for the population around the power plant. The corrosion of the pipes bringing steam from the drill site to the turbines is massive. Drilling that deep and pumping water into the hole ups the risk of earthquakes.
(source: I live in Reykjavík and have witnessed first-hand the increased stench from the Hellisheiði geothermal plant)
Has the lifetime of deep GeoThermal wells been studied at all? Unlike oil/natural gas drilling, a deep geothermal well should provide energy indefinitely barring collapse or obstruction of the well. I'd venture the cost of shutdown and clearing obstructions is fairly low relative to the initial CapEx of the well.
Anyone know as to why this is the case? At first pass it seems like your cutting tools should wear out in proportion to depth. But I suppose as things get warmer tool wear becomes faster. What types of tool materials are used for rock boring? Diamond? Tungsten carbide? Is is more of a "conventional machining" process, or an abrasive / water jet? Or explosive like in hard rock mining?
What else has an effect on cost for deep holes? Shaft length gets longer, so the twist becomes more of a problem if your are driving rotating bits from the top? Does it have to do with removing the material from the bottom of the hole to the top? Others?
> deep geothermal will likely be limited to niche regions like Iceland
True, but aren't there plenty of such regions around the world? In the US I can think of at least Hawaii and Yellowstone.
Not the greatest population centers, but power lines have a good range. Also, Iceland is making good use of its comparative advantage by doing power intensive production like aluminum smelting and bitcoin mining.
It can get pretty crazy the resources consumed by a drill rig during the average week drilling. New bits, roughly 1200 or so liters of fuel every 24 hours, all kinds of sacrificial bits of tube if they are core drilling their holes. Any hundreds of liters of drilling fluids depending on down hole conditions. I was blown away by the consumption when I saw it first hand. The fuel and drilling bits were the craziest. Then all of the maintenance consumables that you go through as a result of running 24/7.
I shudder to consider the quantities of hardware consumed to drill 4km+ you would get all kinds of crazy hard rock down there, not to mention the time it would take for rod pulls.
"Although geothermal energy is still preferable to gas, coal and oil, it's not 'completely renewable and without problems... As soon as you start drilling you have issues to it, such as sulphur pollution and CO2 emission...'"
A bit late to the party but i wanted to back this up by linking to the relevant chapter from the fantastic book by David MacKay: http://withouthotair.com/c16/page_96.shtml
The chapter is only 4 pages long and he quickly works out that if done sustainably, even blanketing the entire country with geothermal plants could provide at most 2 kWh/day per person in the UK. Current consumption is about 125 kWh/day per person. So even without the capex argument, it is just not a very efficient source of energy long-term.
The additional advantage of Geotermal from an operations standpoint it has 0 marginal cost which guarantees it will be producing on most economically dispatched power grids.
I think the real approach to geo should be more focused on decentralized use, instead of trying to do big arrays of holes, like solar, it's in the combination with localization of other technologies in array themselves that seem to offer the most opportunity.
Wind, solar, geo... they all work together better than as a single unit.
And geothermal energy is a too-often-overlooked technology. It's not intermittent like wind and solar. It's more like nuclear but without the emotional baggage. As we try deep decarbonization, we're going to need more things like geothermal (or nuclear) or we'll end up spending like 2 or 3x as much money over-building solar to provide enough power even on cloudy winter days, building many more wind turbines, etc.
The hard part isn't getting to 60-80% clean energy, it's getting that last 20%. Geothermal helps a LOT with that. (As does nuclear, which is why we should be protecting existing nuclear assets until fossil fuels are eliminated... The existing ~20% of our electricity in the US produced by nuclear will make deep decarbonization multiple times cheaper than relying solely on wind and solar alone, plus accelerate deep decarbonization by a decade.)
Places like New Mexico and southern Colorado are good fits for this.
A problem with geothermal is if you draw heat too fast from the ground, the output will decline over the years. If you stop drawing heat, the ground will warm back up and then when you start again, output will be higher than it was when you stopped. So there is some sense in conserving geothermal power when demand for it is low.
So the idea is, you draw from solar when the Sun is shining and draw from geothermal when it's not. By being co-located, you can use the same grid infrastructure and get higher utilization out of your powerlines. You've essentially converted some of your solar energy into a baseload power source. Or you can think about it as enhancing the output and lifetime of your geothermal power source.
(And it's possible that if you have a LOT of extra solar power, you could run a resistive load underground, using the ground as a makeshift thermal battery.)
From what I understand, the big hurdle for 100% renewable is not replacing the power stations that provide base load power, but rather replacing peak load power stations. Hydro is often used for that, but in the Midwest the peaker stations are almost entirely run with natural gas.
Replacing those often involves some way of storing energy that you've generated in a renewable fashion. The issue is that storing large amounts of energy is not easy, especially when you live in an area that could be described as flatter than flat.
> A problem with geothermal is if you draw heat too fast from the ground, the output will decline over the years. If you stop drawing heat, the ground will warm back up and then when you start again, output will be higher than it was when you stopped. So there is some sense in conserving geothermal power when demand for it is low.
This sounds like a battery to me. Good problem to have :)
I think it's possible that geothermal and hydro can get us 20% of our total power (though that relies on very optimistic estimates being correct), but I think that's misunderstanding what we actually need baseload for, which is when wind and solar aren't working to provide either enough, or any, power (for whatever reason). You need to be able to replace all of their power for relatively short periods of time (though to sustain our current lifestyle, probably longer), not 20% of their power all of the time. Being able to ramp up a bunch of normally idle natural gas plants at a moment's notice lets us do that right now, but part of that is that existing natural gas plants don't necessarily all fail at once... whereas wind and solar plans would have pretty correlated failures.
> It's more like nuclear but without the emotional baggage.
... and crazy costs (construction, maintenance, decomissioning, waste disposal, much of it obfuscated under general energy budgets, de facto government subsidy, or optimistic amortization).
If you're interested in tracking the efficiency of your geothermal install, there's an app for that (which I helped build): http://groundenergysupport.com/
When I was in sixth grade I entered a science contest to invent a new form of clean energy. Mostly I entered because I was getting a B in my science class and needed extra credit to get up to an A.
And the thing I "invented" was literally what's in this article, geothermal power. Pump water down near magma, have it turned to steam, have that steam come rushing back up to power turbines.
The problem with my invention was that the company sponsoring the contest was a geothermal energy company.
I'm still proud of myself though, because I thought of the idea independently and it is a pretty damn cool idea for how to get energy.
Iceland has discussed building a ~7TW (I think?) cable to transmit power to the UK.
At least in Reykjavik, hot water is piped directly into homes and used for heating (radiators) as well as hot water (with attendant sulfur smell). My host there told me "my wife doesn't like the smell so, we use heated cold water instead". I had to think for a few seconds to parse the phrase "heated cold water". Oh, right, that's what I call "hot water" :)
It's so abundant, they don't mind the waste. Just leave the windows above the radiator open, the radiator keeps the room warm, you get fresh outside air inside, and the convective flow keeps the air moving. That chilled water is sent back to the geothermal plant and pumped back into the ground to replace the water taken out. IIRC there are definitely been geological issues (earthquakes) as a result of this whole process.
Most of your comment is wrong. They've been discussing building a 1GW cable. 7000 times smaller than 7TW. A 7TW cable would be enough to transmit Iceland's yearly electricity production 700 times over. It produces ~10GW per annum.
Hot water is not piped directly into the homes in Reykjavík, it's heated up "cold" water, with artificially added sulfur. See another comment of mine here: https://news.ycombinator.com/item?id=14274085
In Reykjavík the water you use is not recycled in any way, it's pumped into a sewer from there into the ocean. It's definitely not pumped the >50 km back to Nesjavellir for reprocessing.
I firmly believe that the technology to pump water that turns the waterwheel that powers the water pump (and also something else) must be extracting geothermal energy. We just don't see the details. %%
It would be a whole lot cleaner (and friendlier to the framerate) to have a 3x3 geothermal power plant building with a magma reservoir under one tile, and a water reservoir under another, which transmits power to mechanisms or axles touching it, and maybe also pressurized steam to any pipe touching it.
Yes, this seems much better than coal/oil, but isn't there a finite amount of heat under Earth's crust? Have we studied what would happen if we cool Earth's internal temperature by extracting heat in this way?
The Magnetoshpere which protects us from radiation is generated by the magma under the crust[1]. Eventually, if we interfere with the magma currents too much, don't we run the risk of damaging our magnetosphere?
> isn't there a finite amount of heat under Earth's crust?
We can't make meaningful change over the next million years which is vastly past any reasonable projections.
The earth is 6 * 10 ^ 24 kilograms. Changing that much mass by 1 degree would take ~2000 Joules * 6 * 10 ^ 24 kilograms, but we don't get 100% efficiency so let's say it's 10% for a nice low estimate to get 1.2e + 27J.
Worldwide energy use is 5.67 × 10^20J / year. So circa 2 million years of total worldwide energy supply for a 1 degree change. Of course it's not a static value as nuclear reactions and tidal friction are also adding energy, while energy also slowly escapes though the crust.
I would just guess off the top of my head that, because of the sheer volume of the earths interior and the amount of energy stored there as heat, the energy to run our entire civilisation for 1000's of years would be trival compared to it.
The 4.7 km well is still in the earths crust, not even reached the lithosphere.
As far as the earths interior is concerned it might just be like an era of slightly increased vulcanism.
The heat in the earths core is actively generated as well, by radioactive decay and viscous friction. It's not all just left over heat. In that way it's kind of like asking if windmills will cause the wind to run out. Heat is constantly moving from the interior to the exterior of the earth, and we are really just tapping into that rather than breaching a dam that does not leak.
No. The total heat energy down there is astronomical. And earth is heated by the sun. And the heat removed from the rock isnt being flung out into space. Much of it will return through the ground. We are just moving it a few km up from where it is. The earth is thousands of kms thick. We are toying with heat within the pond scum atop an immense ocean of hot rock.
"The Institute of Economic Studies at the University of Iceland said in a February report that the country will not be able to abide by the COP21 climate change agreement signed in Paris in 2015.
Greenhouse gas emissions are rising in all sectors of the economy, except in fisheries and agriculture, it said."
This is unfortunate. Given Iceland's cheap & abundant renewable energy (2X Norway's electricity production per capita!), they really ought to be following the example set by Norway and prioritising Electric Vehicles through tax policies, etc.
It would be easy to build excellent charging infrastructure for EVs in this island nation - instead you have hordes of tourists driving around the ring road in smelly diesels.
I do see a few Nissan Leafs around Reykjavik and Akureyri, but there is barely any public charging infrastructure for driving between cities and tourist attractions.
Does anyone know where phys.org has their articles from? I suppose it has something to do with Elsevier. Since a LOT of their articles has to do with students and universities.
Overall, they publish a great amount of "copy-paste" articles, either from other news sites and/or student papers. I am 100% sure their reports don't write original articles, just rewrite from other sources. It looks to me that Elsevier has found something new with the information they are tapping from (students/universities)
Interesting . NZ has had a geothermal plant for decades that is situated in a volcanic area (and right next to tourist hotspots of Rotorua and Taupo). They force cold water down and use the steam to drive turbines. No idea on the efficiency but the fact its been operating for decades would suggest its good enough to be viable.
I'm at a loss a bit, are they directly tapping underground sources of hot pressurized liquid and not using some form of heat exhanger? How would they deal with various minerals dissolved in the water from gumming up their turbines or heavy elements escaping into the environment? IIRC there was one geothermal plant (in one of the nordic countries, i don't recall which) sitting by hotsprings that had to replace their piping every few months due to mineral deposits...
random thought: Could geothermal power be considered nuclear power considering half of the Earth's internal energy comes from decaying radioactive isotopes?
> How would they deal with various minerals dissolved in the water from gumming up their turbines or heavy elements escaping into the environment?
This kind of ongoing, predictable maintenance is usually priced into the project, along with a health margin for error, and is rather easy to predict (except when you're one of the first such power plants using a new technology or exploiting a new geography). According to [1], the upfront capital cost for a geothermal plant is 5-6x that of a natural gas plant ($/kW) and the maintenance cost is over 10x ($/kW-yr) but since geothermal doesn't require expensive fuel it can be cheaper than fossil fuel based power (depending on price of fuel). Replacing pipes every few months isn't any different than buying tons of gas if you're still making profit and since geothermal plants rarely run more than 90% of the year because of diminishing returns, there's plenty of time for that maintenance.
> random thought: Could geothermal power be considered nuclear power considering half of the Earth's internal energy comes from decaying radioactive isotopes?
Technically yes, but nuclear power implies a concentrated sample of radioactive material. Radioisotope thermoelectric generators [2], which generate power from the heat of decaying isotopes, are relatively common nuclear power sources in space exploration. They were used on the Apollo 12-17 missions, they still power the Voyager 1 and 2 spacecraft, Cassini, and many more including, most recently, the Mars Science Laboratory rover.
> random thought: Could geothermal power be considered nuclear power considering half of the Earth's internal energy comes from decaying radioactive isotopes?
Only to the extend that all power is nuclear power. Solar power: the sun is a huge fission reactor. Coal: ultimately got its energy from the sun. Etc.
geothermal doesn't use magma, which would destroy the borehole. Its just a hole into very hot rock somewhat near magma. It's still far enough away that water/steam can flow in between the rocks. Steam is what comes up the hole.
Someone more knowledgable than me, please correct me... if they are drilling a hole in the ground and making steam come up from said hole, doesn't that heat up the Earth's crust and atmosphere more than the previous condition without the hole, therefore contributing to higher temperatures (and climate change), making it not that "clean" after all? Maybe cleaner than carbon/petrol, but not ideal for the current context.
>doesn't that heat up the Earth's crust and atmosphere more than the previous condition without the hole, therefore contributing to higher temperatures (and climate change)
It's irrelevant when compared to the amount of energy from the sun. World energy consumption is roughly 5.4 * 10^20 Joules per year. This is 86% of the total energy from the sun that hits the Earth in an hour.
It's like worrying over putting a single drop of poison into the ocean.
Global warming isn't really about heat per se, it's about heat retention. It's the green house gasses reflecting back the latent infrared energy preventing it from escaping to space.
Adding more heat doesn't change the equation, it's how much we retain.
I'm probably no more knowledgeable than you in this area, but I have a free morning, and this is interesting. My hypothesis, is that the heat that we produce or release to generate usable energy, is an insignificant factor in global warming, compared to the solar heat that we trap with greenhouse gases. Let's find some quick simple stats and do some arithmetic, to figure out how much we are directly heating the surface of the Earth.
According to Wikipedia, the global energy production for 2012 was about 5.616e+20 joules, or 156 petawatt-hours. The Earth has about 1.386e+21 liters of water on it, and I will assume that that water represents the bulk of the relevant thermal mass, when considering weather patterns and sea level.
Now, let's estimate the heating caused by that energy. According to www.bickfordscience.com/03-05_State_Changes/PDF/Specific_Heat.pdf, 4,184 Joules of energy applied to 1 KG of water will raise its temperature by 1 degree Celsius, and this scales linearly with mass. Assuming that Earth-water averages out a density of 1 KG per liter, our 5.616e+20 joules, applied over a year to our 1.386e+21 liter water mass, would heat that water by 1.036e-38 degrees Celcius.
It has been a while since I've done a dimensional analysis, and the scale here are so extreme that I can't tell if my result is sensible. However, if my assumptions are reasonable and my math is correct, and the processes that I have chosen to ignore are insignificant (i.e. radiation into space over one year), then all of the heat that we release in the generation of the global energy supply, has a negligible impact on the temperature of the planet.
I imagine any pipes down into the hole will be insulated however there was some work looking at the changes in bacterial make up of soil surrounding these access lines. I can't find reference, but it was mentioned last time this idea was brought up on HN.
[+] [-] chris_va|9 years ago|reply
Conventional geothermal is about 4-5 cents/kWh, on par with natural gas in the US. The dominant capital cost is drilling a large well (you need volume), and so geothermal plants are generally only built in areas that require shallow (1km) wells.
Well costs are ~quadratic in depth. Given how much money has already been spent optimizing drilling for the oil&gas industry, along with how cutthroat that market is, I don't see the cost coming down significantly. As a result, deep geothermal will likely be limited to niche regions like Iceland. And you need deep geothermal to scale it past the existing locations.
I would love to be wrong, since geothermal checks all the boxes for renewables and is also suitable for base load power, but I don't see an obvious path forward short of a drilling tech miracle.
(source: Climate and Energy R&D group)
[+] [-] Beltiras|9 years ago|reply
(source: I live in Reykjavík and have witnessed first-hand the increased stench from the Hellisheiði geothermal plant)
[+] [-] lumost|9 years ago|reply
[+] [-] GregBuchholz|9 years ago|reply
Anyone know as to why this is the case? At first pass it seems like your cutting tools should wear out in proportion to depth. But I suppose as things get warmer tool wear becomes faster. What types of tool materials are used for rock boring? Diamond? Tungsten carbide? Is is more of a "conventional machining" process, or an abrasive / water jet? Or explosive like in hard rock mining? What else has an effect on cost for deep holes? Shaft length gets longer, so the twist becomes more of a problem if your are driving rotating bits from the top? Does it have to do with removing the material from the bottom of the hole to the top? Others?
[+] [-] BurningFrog|9 years ago|reply
True, but aren't there plenty of such regions around the world? In the US I can think of at least Hawaii and Yellowstone.
Not the greatest population centers, but power lines have a good range. Also, Iceland is making good use of its comparative advantage by doing power intensive production like aluminum smelting and bitcoin mining.
[+] [-] gtvwill|9 years ago|reply
I shudder to consider the quantities of hardware consumed to drill 4km+ you would get all kinds of crazy hard rock down there, not to mention the time it would take for rod pulls.
[+] [-] abalone|9 years ago|reply
Article:
"Although geothermal energy is still preferable to gas, coal and oil, it's not 'completely renewable and without problems... As soon as you start drilling you have issues to it, such as sulphur pollution and CO2 emission...'"
[+] [-] phreeza|9 years ago|reply
The chapter is only 4 pages long and he quickly works out that if done sustainably, even blanketing the entire country with geothermal plants could provide at most 2 kWh/day per person in the UK. Current consumption is about 125 kWh/day per person. So even without the capex argument, it is just not a very efficient source of energy long-term.
[+] [-] Rabei|9 years ago|reply
[+] [-] fulafel|9 years ago|reply
[+] [-] arca_vorago|9 years ago|reply
Wind, solar, geo... they all work together better than as a single unit.
[+] [-] Robotbeat|9 years ago|reply
The hard part isn't getting to 60-80% clean energy, it's getting that last 20%. Geothermal helps a LOT with that. (As does nuclear, which is why we should be protecting existing nuclear assets until fossil fuels are eliminated... The existing ~20% of our electricity in the US produced by nuclear will make deep decarbonization multiple times cheaper than relying solely on wind and solar alone, plus accelerate deep decarbonization by a decade.)
An interesting idea is to build geothermal and solar at the same site. Consider areas where these two maps overlap in high potential for both: Geothermal: http://www.smu.edu/~/media/Site/Dedman/Academics/Programs/Ge... and Solar: http://www.nrel.gov/gis/images/map_pv_us_june_dec2008.jpg
Places like New Mexico and southern Colorado are good fits for this.
A problem with geothermal is if you draw heat too fast from the ground, the output will decline over the years. If you stop drawing heat, the ground will warm back up and then when you start again, output will be higher than it was when you stopped. So there is some sense in conserving geothermal power when demand for it is low.
So the idea is, you draw from solar when the Sun is shining and draw from geothermal when it's not. By being co-located, you can use the same grid infrastructure and get higher utilization out of your powerlines. You've essentially converted some of your solar energy into a baseload power source. Or you can think about it as enhancing the output and lifetime of your geothermal power source.
(And it's possible that if you have a LOT of extra solar power, you could run a resistive load underground, using the ground as a makeshift thermal battery.)
[+] [-] Declanomous|9 years ago|reply
Replacing those often involves some way of storing energy that you've generated in a renewable fashion. The issue is that storing large amounts of energy is not easy, especially when you live in an area that could be described as flatter than flat.
[+] [-] simonebrunozzi|9 years ago|reply
This sounds like a battery to me. Good problem to have :)
[+] [-] nickik|9 years ago|reply
It is clean, relativly easy to build, shared tech with gas on the turbine and can have it produce power 24/7.
You just heat up a pot of something and let it cool during the night, still producing energy.
Cheap, green, stable.
[+] [-] Jweb_Guru|9 years ago|reply
[+] [-] afterburner|9 years ago|reply
... and crazy costs (construction, maintenance, decomissioning, waste disposal, much of it obfuscated under general energy budgets, de facto government subsidy, or optimistic amortization).
[+] [-] tclancy|9 years ago|reply
[+] [-] tonystubblebine|9 years ago|reply
And the thing I "invented" was literally what's in this article, geothermal power. Pump water down near magma, have it turned to steam, have that steam come rushing back up to power turbines.
The problem with my invention was that the company sponsoring the contest was a geothermal energy company.
I'm still proud of myself though, because I thought of the idea independently and it is a pretty damn cool idea for how to get energy.
[+] [-] rconti|9 years ago|reply
At least in Reykjavik, hot water is piped directly into homes and used for heating (radiators) as well as hot water (with attendant sulfur smell). My host there told me "my wife doesn't like the smell so, we use heated cold water instead". I had to think for a few seconds to parse the phrase "heated cold water". Oh, right, that's what I call "hot water" :)
It's so abundant, they don't mind the waste. Just leave the windows above the radiator open, the radiator keeps the room warm, you get fresh outside air inside, and the convective flow keeps the air moving. That chilled water is sent back to the geothermal plant and pumped back into the ground to replace the water taken out. IIRC there are definitely been geological issues (earthquakes) as a result of this whole process.
[+] [-] avar|9 years ago|reply
Hot water is not piped directly into the homes in Reykjavík, it's heated up "cold" water, with artificially added sulfur. See another comment of mine here: https://news.ycombinator.com/item?id=14274085
In Reykjavík the water you use is not recycled in any way, it's pumped into a sewer from there into the ocean. It's definitely not pumped the >50 km back to Nesjavellir for reprocessing.
[+] [-] devrandomguy|9 years ago|reply
I just hope that they are being careful not to drill through any adamantine formations. http://dwarffortresswiki.org/index.php/DF2014:Raw_adamantine
[+] [-] logfromblammo|9 years ago|reply
I firmly believe that the technology to pump water that turns the waterwheel that powers the water pump (and also something else) must be extracting geothermal energy. We just don't see the details. %%
It would be a whole lot cleaner (and friendlier to the framerate) to have a 3x3 geothermal power plant building with a magma reservoir under one tile, and a water reservoir under another, which transmits power to mechanisms or axles touching it, and maybe also pressurized steam to any pipe touching it.
[+] [-] cmbuck|9 years ago|reply
The Magnetoshpere which protects us from radiation is generated by the magma under the crust[1]. Eventually, if we interfere with the magma currents too much, don't we run the risk of damaging our magnetosphere?
[1] https://en.wikipedia.org/wiki/Earth%27s_magnetic_field#Physi...
[+] [-] Retric|9 years ago|reply
We can't make meaningful change over the next million years which is vastly past any reasonable projections.
The earth is 6 * 10 ^ 24 kilograms. Changing that much mass by 1 degree would take ~2000 Joules * 6 * 10 ^ 24 kilograms, but we don't get 100% efficiency so let's say it's 10% for a nice low estimate to get 1.2e + 27J.
Worldwide energy use is 5.67 × 10^20J / year. So circa 2 million years of total worldwide energy supply for a 1 degree change. Of course it's not a static value as nuclear reactions and tidal friction are also adding energy, while energy also slowly escapes though the crust.
[+] [-] everyone|9 years ago|reply
http://hyperphysics.phy-astr.gsu.edu/hbase/Geophys/imggeo/ea...
The 4.7 km well is still in the earths crust, not even reached the lithosphere. As far as the earths interior is concerned it might just be like an era of slightly increased vulcanism.
[+] [-] hwillis|9 years ago|reply
[+] [-] sandworm101|9 years ago|reply
[+] [-] Reason077|9 years ago|reply
Greenhouse gas emissions are rising in all sectors of the economy, except in fisheries and agriculture, it said."
This is unfortunate. Given Iceland's cheap & abundant renewable energy (2X Norway's electricity production per capita!), they really ought to be following the example set by Norway and prioritising Electric Vehicles through tax policies, etc.
It would be easy to build excellent charging infrastructure for EVs in this island nation - instead you have hordes of tourists driving around the ring road in smelly diesels.
I do see a few Nissan Leafs around Reykjavik and Akureyri, but there is barely any public charging infrastructure for driving between cities and tourist attractions.
[+] [-] NicoJuicy|9 years ago|reply
Overall, they publish a great amount of "copy-paste" articles, either from other news sites and/or student papers. I am 100% sure their reports don't write original articles, just rewrite from other sources. It looks to me that Elsevier has found something new with the information they are tapping from (students/universities)
PS. The source of their article now is : https://techxplore.com/news/2016-10-geothermal-power-potenti...
PS2. Elsevier seemed my best guess, since a lot of articles discuss research from students. Other articles are a rewrite
[+] [-] zoom6628|9 years ago|reply
[+] [-] Teknoman117|9 years ago|reply
random thought: Could geothermal power be considered nuclear power considering half of the Earth's internal energy comes from decaying radioactive isotopes?
[+] [-] akiselev|9 years ago|reply
This kind of ongoing, predictable maintenance is usually priced into the project, along with a health margin for error, and is rather easy to predict (except when you're one of the first such power plants using a new technology or exploiting a new geography). According to [1], the upfront capital cost for a geothermal plant is 5-6x that of a natural gas plant ($/kW) and the maintenance cost is over 10x ($/kW-yr) but since geothermal doesn't require expensive fuel it can be cheaper than fossil fuel based power (depending on price of fuel). Replacing pipes every few months isn't any different than buying tons of gas if you're still making profit and since geothermal plants rarely run more than 90% of the year because of diminishing returns, there's plenty of time for that maintenance.
> random thought: Could geothermal power be considered nuclear power considering half of the Earth's internal energy comes from decaying radioactive isotopes?
Technically yes, but nuclear power implies a concentrated sample of radioactive material. Radioisotope thermoelectric generators [2], which generate power from the heat of decaying isotopes, are relatively common nuclear power sources in space exploration. They were used on the Apollo 12-17 missions, they still power the Voyager 1 and 2 spacecraft, Cassini, and many more including, most recently, the Mars Science Laboratory rover.
[1] https://www.eia.gov/outlooks/capitalcost/pdf/updated_capcost...
[2] https://en.wikipedia.org/wiki/Radioisotope_thermoelectric_ge...
[+] [-] perlgeek|9 years ago|reply
Only to the extend that all power is nuclear power. Solar power: the sun is a huge fission reactor. Coal: ultimately got its energy from the sun. Etc.
[+] [-] avar|9 years ago|reply
[+] [-] greatNespresso|9 years ago|reply
[+] [-] thatwebdude|9 years ago|reply
[+] [-] idlewords|9 years ago|reply
[+] [-] awqrre|9 years ago|reply
[+] [-] hwillis|9 years ago|reply
[+] [-] mmwako|9 years ago|reply
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[+] [-] mmwako|9 years ago|reply
[+] [-] cowboysauce|9 years ago|reply
It's irrelevant when compared to the amount of energy from the sun. World energy consumption is roughly 5.4 * 10^20 Joules per year. This is 86% of the total energy from the sun that hits the Earth in an hour.
It's like worrying over putting a single drop of poison into the ocean.
[+] [-] deeviant|9 years ago|reply
Adding more heat doesn't change the equation, it's how much we retain.
[+] [-] devrandomguy|9 years ago|reply
According to Wikipedia, the global energy production for 2012 was about 5.616e+20 joules, or 156 petawatt-hours. The Earth has about 1.386e+21 liters of water on it, and I will assume that that water represents the bulk of the relevant thermal mass, when considering weather patterns and sea level.
Now, let's estimate the heating caused by that energy. According to www.bickfordscience.com/03-05_State_Changes/PDF/Specific_Heat.pdf, 4,184 Joules of energy applied to 1 KG of water will raise its temperature by 1 degree Celsius, and this scales linearly with mass. Assuming that Earth-water averages out a density of 1 KG per liter, our 5.616e+20 joules, applied over a year to our 1.386e+21 liter water mass, would heat that water by 1.036e-38 degrees Celcius.
It has been a while since I've done a dimensional analysis, and the scale here are so extreme that I can't tell if my result is sensible. However, if my assumptions are reasonable and my math is correct, and the processes that I have chosen to ignore are insignificant (i.e. radiation into space over one year), then all of the heat that we release in the generation of the global energy supply, has a negligible impact on the temperature of the planet.
[+] [-] ant6n|9 years ago|reply
[+] [-] EGreg|9 years ago|reply
https://dothemath.ucsd.edu/2012/04/economist-meets-physicist...
[+] [-] giarc|9 years ago|reply
[+] [-] StavrosK|9 years ago|reply
Relatedly, though, won't this cool the core?