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Google Releases Geothermal Potential Map of the US
a_hanso writes "The Google funded Enhanced Geothermal Systems research at the Southern Methodist University has produced a coast-to-coast geothermal potential map of the United States. Having invested over $10 million on geothermal energy, Google seems to believe that it is our best bet at kicking the oil habit (especially now that nuclear power has suddenly become disproportionately unpopular)."
Probably about the same time all those wind farms start blowing Earth off it's orbit.
"None can love freedom heartily, but good men; the rest love not freedom, but license." --John Milton
I hope those questions are a joke. Geothermal wells don't go any where deep enough to reach the core. In fact they remain in the mantle, the top layer of the earth. It's only where the core sends a plume of lava close to the surface that geo-thermal is possible. Removing any large amounts of energy from these plumes will make no difference in the core temperature. (about as much change as a fart in a hurricane).
As for question #2, that is one of the limits to the amount of energy we can use on the surface of this planet, and a limit to growth of the human race.
1. What happens to the core when we start pumping large amounts of heat out of the core? How long until it cools enough for our magnetic field to collapse enough to be dangerous?
Here's a fascinating thought experiment that might interest you: What is cold weather?
It's so easy to say that cold weather is the movement of cold air, but that's wrong. "Cold" is not a force or some sort of negative energy that gets applied during winter. Cold is what happens when, if even for a moment, we stop getting enough sunlight to make up for the energy that's lost to space. Every single winter of every single year (and remember that summer on one hemisphere is winter on the other), huge swaths of the planet are losing energy to space. It's enough to bring the frost line of soil down several feet just in the northern US--I'd hate to think how deep it penetrates in Canada.
There is no comparison of the surface area affected by severe winters to the surface area of geothermal wells, and as such, there is no comparing the energy loss between the two.
And keep in mind, nobody's suggesting drilling into the mantle, let alone the core. That's known as a volcano. We don't really have materials to safely handle that sort of well. And the crust of the earth is so remarkably thin compared to the size of the mantle... well, I'm not sure we'll have to worry about it for millenia if not more.
The chance that humans could impact such a large object in an way, is pretty slim.
This argument sounds familiar for some reason ...
Wait, this question was serious? The heat from the mantle will eventually migrate upwards anyways. And turning it into electricity won't introduce more heat into our atmosphere than we already are from burning coal/ natural gas. Considerably less so, especially without any CO2 production.
Geothermal can last a long, long time. Although I should point out that scharkalvin is wrong (about this one): Google's EGS plan doesn't use geothermal plumes like most geothermal power does, it just uses the Earth's natural heat at about 6.5km down (which occurs everywhere to various degrees.) Hence, the gradient map.
Oh, and lest we forget, sun unleashes something like 1*10^17 joules of energy on the Earth per second. It would take an absolute shitload of geothermal stations, probably more than we could ever effectively build, to add any considerable amount to that.
"None can love freedom heartily, but good men; the rest love not freedom, but license." --John Milton
You do realize that we already pipe energy from one side of the country to the other right? The "Long Wires" are for the most part already there. Upgrade, enhancements will be need but the framework is in place.
Actually, we don't. At least not significant amounts.
The USA is essentially 3 main power grids without much interconnection between them (but it's planned).
Check out this map:
http://www.npr.org/templates/story/story.php?storyId=110997398
(turn off the "proposed" lines to see what the grid looks like today)
FTFS:
(especially now that nuclear power has suddenly become disproportionately unpopular)
There are lots of problems with this phrase:
1. "especially now" and "suddenly" imply that opposition to nuclear power is something new, rather than something that's had at least rumblings about for over 50 years.
2. "disproportionately" doesn't describe what you're comparing it to. I'm guessing it's the cost of nuclear power, factoring in the average cost per KwH, the incidence of accidents, and the average cost per accident, but that's little more than a guess.
So that little editorial comment seems to read:
"Nuclear power is safe and fantastic, but those environmentalist nutjobs have suddenly convinced everybody to hate it for no good reason."
The more reasonable comment, if you were going to make any general statement at all, would be something like:
"Nuclear power seems to be mostly safe, but environmentalists have convinced many people that it's a bad idea because of a few notable accidents."
Or, you know, you could just leave that out entirely. Knowing where geothermal energy could be a viable source is worth doing regardless of what happens to nuclear power plants.
I am officially gone from
A hurricane has about 6e14 W. You might be able to create somewhere around 8kJ/day if you found a way to harness all your gas. That's about 1e-1 W. That's a difference of 15 orders of magnitude.
The earth has geothermal energy of about 1e31 J. 15 orders of magnitude less than that is 1e16J. That's less than what Zimbabwe uses annually. The core is radioactively replenished at 30TW. As of 2007 there was already 10GW of geothermal electric capacity. That's only 4 orders of magnitude. So no, it's not a fart in a hurricane. I am flabbergasted by these findings. I thought for sure you were right.
Are you keyword triggered or something?
Once again we encounter this silly notion that most power in the US is used for "people" (residential needs). Residential electricity consumption is just over a third of the total US electricity demand. If power is cheaper in some part of the country, heavy industry and high electricity-consumption commercial will move there. That's why we have so many of our aluminum smelters in the Pacific Northwest, feeding off of cheap hydro. It's why aluminum is Iceland's leading export despite there not being a single bauxite mine in the country.
Furthermore:
A) There are "hot" areas out east as well -- just not as major or widespread. But you honestly don't need much; the total power potential from EGS is so much greater than the demand.
B) You don't have to produce from the hottest areas; it just means more well cost per unit power generated to use a cooler area.
C) Power *can* be shipped cross-country with rather low losses, via HVDC lines. Which are surprisingly affordable; HVDC has a lot of per-terminal cost but a not-unreasonable per-mile cost.
Lastly:
"Get away from the Northeast, the West Coast, and Texas".
In case you didn't notice, the greatest heat potential areas *are* near the west coast.
Seen on a Japanese food processor: "Not to be used for the other use."
Yes, there are idiots. So? Even the Audubon Society supports wind power, so long as you do the (required) bird safety studies and best-practices for bird strike amelioration. Bird turbine deaths are a drop in the bucket compared to most anthropogenic bird death causes, even taking into account its currently limited scale. Our worst are glass windows and the raising of housecats, but everything from habitat destruction to hunting to industrial waste ponds to vehicle strikes kills far more birds than wind turbines. The "wind turbines are bird cuisinarts" notion came from one old, specific wind farm, built in as horrible of a location and manner as possible (Altamont Pass). It was from before the bird strike issue was well known. They built it in the middle of a raptor flyway, using small, low, closely spaced, fast-spinning turbines whose tower structure was inviting for birds to try to perch on. It was a perfect recipe for disaster, and doesn't apply at all to modern wind farms.
There are some concerns about EGS, mainly about earthquakes; however, the quakes are low-level, and all you're really doing is just accelerating what was going to come naturally. Apart from that, geothermal is about as non-intrusive of a power generation method as you can get -- just a plume of steam rising in the distance. There's even one interesting geothermal approach being pursued out there that eliminates even EGS's problems. Instead of drilling open "wells", then fracking a reservoir, then running water through the reservoir, instead you drill a self-contained water-cooled "heat sink" of thermally-conductive grout. Your water working fluid never touches the rock (only the grout does), so it never takes on corrosive minerals or waste gasses, there's no earthquakes (because there's no fracking), and it works reliably, equally well everywhere in the world with the same heat gradient (instead of just in areas with good potential reservoir rock layers) since you don't have to get water to run through a fracked rock layer in just the right manner (one of the big problems with EGS is that you never really know where your water is going to go once you inject it until you drill the well, frack the rock, cross your fingers and try).
Seen on a Japanese food processor: "Not to be used for the other use."