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)
(source: I live in Reykjavík and have witnessed first-hand the increased stench from the Hellisheiði geothermal plant)
- contemporary photovoltaic panels require all sorts of strange metals to make, which have environmental impacts via mining. This might change with new materials. Solar also tends to have quite high carbon dioxide impacts due to the manufacturing process. These are obviously way less than gas or coal, but about double compared to other renewables and nuclear.
- hydroelectric is notorious for destroying huge ecosystems stretching far above and far below the dam and its reservoir. Hydro is so bad that California doesn't let large projects count in the Renewable Portfolio Standard.
It's tough; there's no perfect energy source.
Certain kinds do (e.g. CdTe and CIGS), but not the kind that you'd put on your house. If modern solar panels required significant amounts of rare earths they wouldn't be as cheap as they are.
"Solar also tends to have quite high carbon dioxide impacts due to the manufacturing process."
About 30g/kwh of CO2 vs. coal's ~900g/kwh, and a lot of that is simply because it is usually currently made without green power (i.e. it will go down).
"It's tough; there's no perfect energy source."
There's a lot of half truths told about really good energy sources.
- wind: 11 g / kWh 
- nuclear: 12 g / kWh 
- solar PV: 45 g / kWh 
- gas: 450 g / kWh 
Of course, 12 g vs 45 g is NOTHING compared to 45 g vs 450 g (and coal is another 2x atop gas!), so I'm making a bit of a mountain out of a molehill.
As it stands, of course, it makes everything worse.
This is not quite right. A few kinds of contemporary PV require exotic elements such as indium, gallium, and tellurium. But the market is dominated by crystalline silicon cell technology (about 93% market share in 2015): https://www.ise.fraunhofer.de/content/dam/ise/de/documents/p...
10 cubic kilometers of water: It's the worldwide-recognized ratio under which hydro is considered renewable, and above which the ecosystem destruction is too important.
Of course, dirty alternatives have their own toll on wildlife.
15,000x fewer than house cats do though.
Having said this, I think the risk of man-made earthquakes is exaggerated. I mean, I think it might be possible to trigger small seismic events, but they should not be the destructive kind. I doubt we can trigger massive destructive eathquakes like this. Also, from what I understand, smaller seismic evnts should lower the energy that the bigger ones have.
It might sound alien if you have a certain way of looking at things, but really, is my question not logical?
I wonder similar things about solar - what effect is there on global weather patterns when enough solar energy to make a difference is extracted from the environment? Like, what would happen globally if the entire state of Arizona was in the shadow of solar arrays?
So the Earth has a heat stored which is (4K miles / 50 feet)^3 times larger than a blast furnace.
i.e. about 7x10^16 times larger.
If everyone on Earth had their own personal blast furnace, we'd be controlling 10 million times less energy than what's in the core of the Earth.
Similar calculations apply to other calculations. A Physics 101 calculation I did (years ago) was how much a tidal plant would slow down the rotation of the Earth. The answer was by less than a second a day, after 100 years of running.
> ke, what would happen globally if the entire state of Arizona was in the shadow of solar arrays?
The plants wouldn't grow. :)
But seriously, the energy has to go somewhere. If it's hitting solar panels instead of the ground, the net effect to the world is essentially zero.
Maybe locally the ground would be cooler because it's in the shade. But that's about it.
That means that if you built 100 of those plants that in 1 year you'd change the length of the day by 1 second.
The 2011 Tōhoku earthquake and tsunami released 3.9×10^22 joules of energy and changed the day by just over a microsecond. A single Tsar Bomba releases 2.1×10^17 joules, so you'd need the energy of around 200 thousand of those to produce the same amount of energy as the earthquake, and then assuming you can direct that energy you need 1000 times more to shift the day by a second instead of a microsecond.
That means that each one of your proposed tidal plants would need to generate the energy of 20,000,000 Tsar Bombas per year.
That's one Tsar Bomba's worth of energy being released every 1.5 seconds at each one of those 100 plants. Buy stock in sunscreen companies now!
Each one of your 100 plants would satisfy all of current yearly world energy production in just 30 minutes.
I'm too lazy to calculate what that would do to the surrounding area, but I'd wager that they're going to severely depress local property prices due much of the surrounding beach-side property area now being turned into permanent molten lava.
The good news is you could probably build really good wind power plants now, due to constant hurricane winds not seen on Earth since the K–T impact, but I digress.
I didn't check your molten rock calculation but given how off your tidal plant calculation is I wouldn't be surprised if it's way off as well.
4. ((5.67x10^20)/(2.1x10^17))/1.5/60 = 30
It was a recollection of a problem from 25 years ago for crying out loud.
Thinking about it some more, it's probably slowing down the rotation of the earth by 1 second over the course of 100 years. Not 1 second per day. Which makes about 4-5 orders of magnitude difference.
> I didn't check your molten rock calculation but given how off your tidal plant calculation is I wouldn't be surprised if it's way off as well.
The point was to get a "back of the envelope" calculation. Not to get a precise answer to 4 decimal places.
What's with the bike shedding? Is the point here to have a discussion, or to prove that you're smarter than everyone else?
he showed his work for his first calculation. Looked reasonable to me.
> And these furnaces are maybe 50 feet across. [...]
> So the Earth has a heat stored which is
> (4K miles / 50 feet)^3
It also seems to assume that a 50ft^3 blast furnace contains energy equivalent to 50ft^3 of molten mantle. If you look at diagrams of blast furnaces you can see that a relatively tiny part of them is actually molten material.
Not being able to find numbers on the stored joules of industrial blast furnaces, I'm just going to just state that 50ft^3 of mantle has a crapload more potential energy than 50ft^3 of blast furnace, most of which is air, equipment & empty space, not molten material.
He is right that there's at least as much energy stored in the earth as he's saying, but it's going to be a crapload more than that.
The insides of blast furnaces are also significantly colder than the average temperature of the mantle.
Fermi was known for asking questions like "how many gold balls git into a suitcase". The point isn't to get a perfect answer. The point is to get a reasonable answer.
In this case, the point is to answer the OP question in laymans terms. Using not much more than reasonable assumptions, and grade 5 math.
Or, you can bike shed over details.
Still off by a factor of 1000, a microsecond is one millionth of a second.
* [...] 20,000,000,000 Tsar Bombas per year
* One Tsar Bomba going off every 1.5ms
* World energy production satisfied in 1.8 seconds
We're also going to need more sunscreen.
I imagine that if we were able to tap into deep geothermal energy the continuing exponential growth would eventually pass some sort of geothermal limit point.
But I am a bit sceptical to the no impact scenario. We know a lot allready about the inside of the earth, but afaik we do not really understand it. There are many flows underneath etc. and small changes can have big impacts. Look for example at the amount of artifical CO2 from humans. It is tiny in comparison with the rest of the atmosphere. And yet it gives us a lot of troubles.
And about geothermal: well, here in germany there have been allready some minor earthquakes, probably caused by geothermal plants ...
Even if you don't understand French, you can look at pictures of this article: http://www.lefigaro.fr/actualite-france/2013/11/19/01016-201...
Another experiment was stopped in Switzerland for the same reason: https://www.theguardian.com/world/2009/dec/15/swiss-geotherm...
As for solar, the incoming energy would have been mostly converted to heat. When we use the electricity produced, we convert it back to heat again. If the entire state of AZ were covered with solar panels, and all the energy spent in NY, there would be some localized changes but not much in the global scale. For the foreseeable future, we are not even close to covering up just 1% of the land area of AZ.
Well, with efficiency gains in the latest years energy consumption (not only electricity) actually is constant or decreasing in developed countries. Add to that decreasing population fertility and if you expect that developing countries are going to follow the same trends after a certain threshold then that's not a good assumption long-term.
For me, the more interesting one, which was the 'bad guy' in the forgettable movie "The Core". The earth's magnetic field is created by the motion of the fluid iron (which is conductive) surrounding the solid core. That it is moving and carries charge creates a dynamic dynamo which determines the strength of the magnetic field. Changes in the fluid are why the magnetic poles move around and sometimes change places.
The number 1 feature of the magnetic field (for me at least) is that it deflects the solar wind (those charged particles racing out from the Sun) which would otherwise collide with the gases surrounding our planet and accelerate them outward. Eventually stripping the planet of most of its atmosphere.
One of the less well known ways the solar system could wipe out humanity.
Worst case, you run them continuously at half capacity, but then your cost per kWh is about 2x.
Wait, I haven't looked at geothermal in a long time so I'm not at all up to speed on the current state of the at. But previously you wrote:
>and so geothermal plants are generally only built in areas that require shallow (1km) wells
That sounds like your "30 years" number there is for shallow wells. Intuitively it doesn't seem like this logic would necessarily be identical for deeper wells: obviously at some depth the rock is always extremely hot (or, in fact, molten). The article seems to indicate that they expect a deeper well to produce higher temperatures and pressures, in turn allowing more energy production, and that seems like it'd make sense. Maybe 1km vs 5km makes no difference in lifetime beyond that, but does your analysis include deep wells already in an equivalent area? Otherwise it doesn't seem reasonable to extrapolate past lifetimes of shallow wells to future lifetimes of deep wells, even ignoring that they say they'll be able to achieve far higher energy generation per well.
There are physical limits to the heat capacity of the rock, and the heat flux into the region. Deeper wells are not necessarily hotter. Going hotter adds other costs (drilling mud, water=>co2, casement, etc), so its a big multivariate optimization.
Not if you keep pumping in water to run a steam turbine.
I assume that's how geothermal energy works, and I'm not going to double check.
Are you being serious? In terms of known capabilities the Kola borehole shows that even with older tech we can drill down to over 12km in depth, and there have been decades [1,2,3] of efforts drill all the way through the Mohorovičić discontinuity into the mantle (20+km minimum from a continental starting point, 5-10+km from ocean). Lithosphere/mantle boundary tends to be defined by temperature, in that around 1800°F is when the weakest common mineral (olivine) begins to exhibit viscosity. Well before that it'd reach the point where the amount of pressurized water we could pump through it wouldn't be able to keep up with new thermal load. So yeah, at some depth the rock is always extremely hot.
In terms of economics though of course there is some set of balance points for a given level of tech and economics between cost of drilling to a given depth, gains in lifetime/power density, maintenance costs, costs/losses of actually moving working fluid from heat point to generator, reliability advantages, etc etc. Presumably experts go through and consider all of this, it should be tractable within some set of risk bars. If an experienced power company is actually putting down millions on doing a project after evaluation, I see no reason to doubt that they've done the math to their/their investors' satisfaction to a level sufficient for a pilot project.
I don't know what the Mohorovičić discontinuity is, but I'm sure it doesn't change this physics fact.
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?
Think of a telescopic antenna. That structure is similar to what is done to bore a well. You start with large casing diameter and add progressively smaller casings until you reach the target depth. The deeper you go the bigger the casing you must start with. Offshore deep water stuff can be a meter in diameter with 10cm solid steel walls; monstrously heavy and costly materials. And you use kilometers of the stuff.
There are a lot of reasons why costs scale as they do with depth; casing is just one of the more obvious.
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.
...how deep do you have to go to get to the 400C temperature level on some of those volcanoes??
Also many hot springs could be potential GeoThermal candidate areas http://www.hotspringsenthusiast.com/USsprings.asp
That said, geothermal activity isn't confined to the park borders, and there may be a suitable spot outside of the park. But again, politics. Building a geothermal plant in the middle of natural gas country would be a challenge.
Small note about Iceland- My web host (1984) is located there, and the servers run on 100% geothermal. That, in combination with the stellar privacy laws, make Iceland a nice fit for me.
That said, I agree that it would take a lot to get anything like that built.
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...'"
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.
> Other places in the world have more promising hot dry rocks, so if you
want to know the geothermal answers for other countries, be sure to ask a
local. But sadly for Britain, geothermal will only ever play a tiny part.
Wind, solar, geo... they all work together better than as a single unit.
If you combine it with renewables, you get high fluctuation of demand from the grid, which selects for the exact opposite technology (higher opex, lower capex). Natural gas fits the bill, so that is where the market is going.
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:
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.)
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.
Since we have decent short-term storage tech, it's not the peaker plants I worry about but the constant baseload. Peakers will be replaced by utility-scale storage.
One factory is producing batteries now, and Tesla is announcing three or four new gigafactory locations by the end of the year.
It's a start.
Tesla held a grand opening on July 29, 2016 of the operational facility, having only three of the final 21 "blocks" of the gigafactory built out, or approximately 14 percent of the final factory size expected by 2020. By September 2016 Tesla had spent $608 million on Gigafactory.
I still feel like the reluctance to invest in pumped storage is ultimately going to be what does us in.
I think there's room for both, as you can put batteries just about anywhere and at nearly any scale, while pumped hydro works best for large scale. Gigawatt-level for ~10 hours at a time potentially... Largest facility is 3GW for about 10-12 hours, about the same as the yearly battery production the completed Gigafactory will have:
I do think the difference between pumped and battery storage will get closer, however. And battery power has the advantage of option value since you can build it much faster (about 10 times faster) than a big pumped hydro station.
Indeed, we will likely end up using a wide variety of technologies for storage.
Spodumene is found in and with granite and quartz. Granite and quartz make up 75% of the earth's crust. I don't know how much by weight is spodumene but it's certainly extremely common- much more so than any common metals.
Spodumene is ~6-7% lithium by mass and is mined in an open pit, so no worries about soil or water pollution. It's separated from other rocks by grinding, flotation, and then acid. Very few people like acid in their industrial processes but I will note that lithium production uses way less hydroflouric acid than oil refining. The final stage uses sulfuric acid and while again acid is never good, sulfuric acid is one of the most-used and most-produced chemicals. Most minerals require sulfuric acid for extraction. It comes in a bottle of drain cleaner. Mining lithium rock is as economically painless as buying blasting powder and excavators, and as environmentally painless as... well nothing. The pollution is basically negligible.
>Lithium is one of the most prevalent elements on earth. Spodumene (rocky lithium ore) is likely to be a very important economic source in the future as it is much more common than the brine currently used to manufacture batteries. Brine requires a water pump to extract, spodumene requires mining like any normal mineral, but it's found in extremely high quality deposits in the US including single crystals up to 47 feet across. That means higher quality lithium in addition to greater availability.
>Spodumene is ~6-7% lithium by mass and is mined in an open pit, so no worries about soil or water pollution. It's separated from other rocks by grinding, flotation, and then acid. Very few people like acid in their industrial processes but I will note that lithium production uses way less hydroflouric acid than oil refining. The final stage uses sulfuric acid and while again acid is never good, sulfuric acid is one of the most-used and most-produced chemicals. Most minerals require sulfuric acid for extraction. It comes in a bottle of drain cleaner. Mining lithium rock is as economically painless as buying blasting powder and excavators, and as environmentally painless as... well nothing. The pollution is basically negligible.
I didn't know the gigafactory was gonna do component-level recycling, that's pretty cool. I think it should be relatively easy to separate the metals from the SEI and graphite/lithium in a recoverable way, but processing the SEI has to be pretty complex. Maybe acid would do it- at that point it would probably be worth it to recycle the lithium but you'd have to set up an entire process line just to be able to add it to raw feedstock ore. It'll take a LOT of battery recycling before that's more profitable than selling it as clinker.
Molten salt is interesting though, and I am not particularly familiar with that.
This sounds like a battery to me. Good problem to have :)
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.
Ivanpah is expensive and consistently underperforms and has to make up the difference with natural gas. It freezes solid each night and has to be reheated. The nature of thermal solar also means you can't really take advantage of scale, so the problems aren't likely to get any better even if they get built even bigger.
There is essentially zero chance that solar thermal will ever be better than batteries. Ivanpah has 392 MW of capacity @ $2.2 billion, and produces 1.75 GWh per day. Utility scale solar panels are below $1.42/watt- $557 million installed, with land, tax, and inverters. The average price of lithium batteries is below $150/kWh, which would be 788 million for 3 days of storage. Altogether that's 61% the cost of Ivanpah using the average prices from last year. It's also roughly on par with current electricity prices (12.2 cents vs 10.3 cents, but NB residential is 12.6 cents)
Solar city claims panels costing 55 cents per watt and Tesla expects to get below $100/kWh for cells by 2020. If those prices held the cost for a solar plant with 3 days of storage would be 740 million, and the cost of electricity would be 6.8 cents/kWh.
It helps tremendously. I do think we'll use batteries for immediate power instead of natural gas. And the natural gas plants we DO have (hopefully not many of them!) could be more efficient because we won't have to ramp them up and down quickly, so we can use the much higher efficiency combined cycle plants.
(But this idea of replacing nuclear with renewables and peakers seems really dumb to me... it's clearly a step backwards in emissions when we should be targeting fossil fuel plants for shutdowns. The fact that supposedly "green" people are pushing this is really, really weird.)
... and crazy costs (construction, maintenance, decomissioning, waste disposal, much of it obfuscated under general energy budgets, de facto government subsidy, or optimistic amortization).
The costs for construction are very high, for one main reason: time. Due to inexperienced contractors, legal battles, etc, it often takes a decade or more to finish a nuclear plant which DRAMATICALLY increases costs and reduces the option value. But all that could be dramatically reduced, in principle, without sacrificing safety or even needing dramatically new designs. Nuclear innovation really needs to focus on the construction process. Get that down to 2 years or less, and the cost problem will be solved.
Are you aware of the Westinghouse bankruptcy due to nuclear projects, possibly taking Toshiba under with them?
(Just kidding, that's a cool app.)
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.
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.
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'm very surprised to find that the hot water is heated cold water. Where is it heated? Offsite, with geothermal plants, I must assume? Otherwise I'd be VERY confused about how my host would not know that he had 2 separate water heaters. Seems quite odd that a local would not know this, but I guess that's how rumors work.
Is the hot water in radiators similarly offsite-heated water?
There are exceptions, but generally hot water is piped directly into homes in Iceland from municipal heating. There's no domestic water heaters. There are dual hot & cold water pipes everywhere. The hot water that comes out of the tap is from the same source that's in the hot water radiators.
In the case of Reykjavík the hot water is initially cold water heated at Nesjavellir and at  you can see an article in Icelandic about the pipe. It's 27km of 80x90cm pipe that can transfer 1600 liters of 100 degree hot water per second. Here's the pipe on Street View: https://goo.gl/jFzvYN
The reason they heat up cold water is simply because most of the time when you find an abundant natural heat source it doesn't also come with an abundant natural water source. Therefore you pump cold water in, mix it with the heat, and pump out hot water.
I don't know what fancy technology they use for this at Nesjavellir, but in some rural areas this setup is literally just a coiled pipe dropped into a hot spring.
I did see one of the very large geothermal plants, but am having a hard time remembering where it was. Either on my way to/from Thórsmörk, along the golden circle, or on a drive to Snaefellsnes.
Thanks again for your insight!
Perhaps you meant Iceland's average power production is 10GW?
I just hope that they are being careful not to drill through any adamantine formations. http://dwarffortresswiki.org/index.php/DF2014:Raw_adamantine
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.
The Magnetoshpere which protects us from radiation is generated by the magma under the crust. Eventually, if we interfere with the magma currents too much, don't we run the risk of damaging our magnetosphere?
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.
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.
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.
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
random thought: Could geothermal power be considered nuclear power considering half of the Earth's internal energy comes from decaying radioactive isotopes?
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 , 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 , 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.
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.
It's actually super annoying that the same word "geothermal" is used for both. If I were emperor of the world, I'd ensure that the proper "ground-source heat pump" were used instead of the criminally misleading "geothermal."
Ground-source heat pumps are not energy sources, they consume energy.
What Iceland is doing is actually developing an energy source.
Reykjavík artificially adds sulfur to its hot water to reduce the corrosion of their hot water pipes.
I can't find a source for that in English but there's one in Icelandic, it's the "Vinnslutæknileg vandamál við vinnslu jarðhita" section.
Seems like Iceland could really use some sort of myth/fact information as they continue look to grow their tourism.
They have very little incentive to "correct" people
I also know some Iceland natives who actually like it, so I wouldn't completely dismiss it as a tourist trap.
If you have an issue with how it's marketed, I'd suggest inquiring against it.
"If I were emperor of the world..."
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.
Man, every once in a while you remember the scale of energy when you're talking about the sun. Good lord.
It outputs our yearly energy usage in about a microsecond, and converts 4 million tons of mass to energy per second.
However, per unit volume, it's putting out energy about the same as a compost heap.
Adding more heat doesn't change the equation, it's how much we retain.
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.
Relatedly, though, won't this cool the core?