4 ms·

Massive Energy Skyscraper Proposed On U.S.-Mexico Border

38 points by samsolomon 14y ago

dmotles 14y ago
Do you seriously get surplus energy despite pumping water from 46 miles away and then 2000+ ft up in the air?
- mmphosis 14y ago
  I was wondering about that too. Plus the energy required to desalinate the seawater. http://en.wikipedia.org/wiki/Energy_tower http://en.wikipedia.org/wiki/Energy_tower (downdraft) My first thought was that they were building an updraft tower. http://en.wikipedia.org/wiki/Solar_updraft_tower http://en.wikipedia.org/wiki/Solar_updraft_tower http://www.livescience.com/2644-giant-solar-tower-power-future.html http://www.livescience.com/2644-giant-solar-tower-power-futu...
  - ndonnellan 14y ago
    Me too. The difference is that a solar chimney makes sense, kinda. I have no idea what this downdraft tower nonsense is. Converting potential energy to kinetic? 46 miles of pumping expensive water?
    - richardjordan 14y ago
      Right... I've heard of the concentrated solar towers which create an updraft to drive turbines in a very tall chimney, and seen suggestions that they COULD be made to be net energy return on energy investment positive. But this one is pretty new to me. I think it's time to pop over to see what the folks on TheOilDrum.com have had to say about this - they must have seen it and are probably ripping it apart by now.
  - brc 14y ago
    From your link: "no data on a working pilot plant have ever been collected." I smell snake oil.
ximeng 14y ago
Follow up: http://www.forbes.com/sites/davidferris/2013/03/26/your-energy-skyscraper-questions-answered/ http://www.forbes.com/sites/davidferris/2013/03/26/your-ener...
jayfuerstenberg 14y ago
A Canadian company, AVE Designs, has a similar idea but with an upward moving vortex... http://vortexengine.ca/index.shtml http://vortexengine.ca/index.shtml
racbart 14y ago
I really like the idea of solar updraft tower, where air moves the other way: http://en.wikipedia.org/wiki/Solar_updraft_tower http://en.wikipedia.org/wiki/Solar_updraft_tower It's disadvantage is that it requires much more land, but it doesn't require water on the other hand. As someone noticed, the water-powered downdraft version requires pumping water from 46 miles away and then 2000+ ft up.
drucken 14y ago
Wait, what... 1. massive water dependency in middle of the desert 2. dependency on pipeline through foreign territory 3. dependency on foreign border integrity 4. adjunct to military territory ...mmm, what could go wrong?
alimoeeny 14y ago
something is not quite right here, does this make sense at all to anybody? even if for some reason air on the top is hotter than the air next to the hot ground, after a short while the draft itself, makes a local equilibrium, and it is hard to believe you can over come this by spraying water and cooling the bottom of the tower, and all of this just by testing on a 4 feet tall model in Maryland?!
graycat 14y ago
My take was that the crucial 'energy' issue was the huge latent heat of evaporation of water that cooled the air at the top of the tower. So, the air falls in the tower partly, maybe mostly, because it is cooler and, thus, more dense, not because the air is more dense because it is wetter (is air less dense than water vapor?) but because it is more dense because it is cooler. Then I would wonder how to recapture the water without losing a lot of energy, that is, would be fighting the huge latent heat of evaporation again? And I would wonder just why bothering to desalinate the water?
- deleted 14y ago
  [deleted]
- chii 14y ago
  > And I would wonder just why bothering to desalinate the water? perhaps it sucks to have salt deposits due to the evaporation?
  - chroem 14y ago
    One word: corrosion. I honestly don't think this idea is too far fetched, though it's going to need subsidies to get going. If it all works out, then it would be pretty revolutionary.
  - graycat 14y ago
    Sure, but's got to be much cheaper to scrape off and shovel out the salt than to separate it by reverse osmosis, etc. Besides, to save on the scraping, might line the relevant areas with some tough, flexible plastic and, then, periodically shut down, remove the plastic, flex it to break off the salt, reinstall, and continue.
brc 14y ago
EROEI will kill this thing stone dead, if the world is still thinking rationally. Note that it is essentially a solar installation, it doesn't really say if it works during the night. But you can safely assume that if it works on temperature, the headline 'nameplate' figure of 500 gw is only available in peak conditions. It says it uses desalinated water - which is a very energy intensive operation- so at best I figure it would be mildly energy-neutral, at worst it would actually be an energy suck. Then there is the small matter of all the embedded energy in the worlds second tallest structure. The costs are $1 billion for the tower, $100 million for the pipeline, and desal plants are about a $1b a piece these days. That's $2.1 billion invested - not including transmission lines - that's going to take a very long time to earn back. It looks like a subsidy farming exercise to me, or possibly a stock pump'n'dump scheme.
- richardjordan 14y ago
  Any time people think in terms of EROEI they get an upvote from me, as it's the problem with so many plans. I was hoping from the headline that this was a conc. solar tower or something similar, as have been described in the past and which have a chance of being EROEI positive. Sadly few people see the world in the eyes of basic physics and energy return on energy investment. Most of the utopians who believe we'll think ourselves out of the energy crisis without having to make any lifestyle changes or depopulate tend to rely on arguments that are almost always EROEI negative.
fernly 14y ago
"Solar Wind Energy has said... that each tower would require a permanent workforce of 1,000 people." Doing what, exactly? That has to be a bogus number.
Cryode 14y ago
What a giant eye sore.
gavanwoolery 14y ago
Is it wrong that the first thing I thought of was this: http://majorslack.com/pics/screenshots/redalert_03.jpg http://majorslack.com/pics/screenshots/redalert_03.jpg ?
deleted 14y ago
[deleted]

38 points by samsolomon 14y ago

dmotles 14y ago

Do you seriously get surplus energy despite pumping water from 46 miles away and then 2000+ ft up in the air?

mmphosis 14y ago
I was wondering about that too. Plus the energy required to desalinate the seawater. http://en.wikipedia.org/wiki/Energy_tower http://en.wikipedia.org/wiki/Energy_tower (downdraft) My first thought was that they were building an updraft tower. http://en.wikipedia.org/wiki/Solar_updraft_tower http://en.wikipedia.org/wiki/Solar_updraft_tower http://www.livescience.com/2644-giant-solar-tower-power-future.html http://www.livescience.com/2644-giant-solar-tower-power-futu...
- ndonnellan 14y ago
  Me too. The difference is that a solar chimney makes sense, kinda. I have no idea what this downdraft tower nonsense is. Converting potential energy to kinetic? 46 miles of pumping expensive water?
  - richardjordan 14y ago
    Right... I've heard of the concentrated solar towers which create an updraft to drive turbines in a very tall chimney, and seen suggestions that they COULD be made to be net energy return on energy investment positive. But this one is pretty new to me. I think it's time to pop over to see what the folks on TheOilDrum.com have had to say about this - they must have seen it and are probably ripping it apart by now.
- brc 14y ago
  From your link: "no data on a working pilot plant have ever been collected." I smell snake oil.

ximeng 14y ago

Follow up: http://www.forbes.com/sites/davidferris/2013/03/26/your-energy-skyscraper-questions-answered/ http://www.forbes.com/sites/davidferris/2013/03/26/your-ener...

jayfuerstenberg 14y ago

A Canadian company, AVE Designs, has a similar idea but with an upward moving vortex... http://vortexengine.ca/index.shtml http://vortexengine.ca/index.shtml

racbart 14y ago

I really like the idea of solar updraft tower, where air moves the other way: http://en.wikipedia.org/wiki/Solar_updraft_tower http://en.wikipedia.org/wiki/Solar_updraft_tower It's disadvantage is that it requires much more land, but it doesn't require water on the other hand. As someone noticed, the water-powered downdraft version requires pumping water from 46 miles away and then 2000+ ft up.

drucken 14y ago

Wait, what... 1. massive water dependency in middle of the desert 2. dependency on pipeline through foreign territory 3. dependency on foreign border integrity 4. adjunct to military territory ...mmm, what could go wrong?

alimoeeny 14y ago

something is not quite right here, does this make sense at all to anybody? even if for some reason air on the top is hotter than the air next to the hot ground, after a short while the draft itself, makes a local equilibrium, and it is hard to believe you can over come this by spraying water and cooling the bottom of the tower, and all of this just by testing on a 4 feet tall model in Maryland?!

graycat 14y ago

My take was that the crucial 'energy' issue was the huge latent heat of evaporation of water that cooled the air at the top of the tower. So, the air falls in the tower partly, maybe mostly, because it is cooler and, thus, more dense, not because the air is more dense because it is wetter (is air less dense than water vapor?) but because it is more dense because it is cooler. Then I would wonder how to recapture the water without losing a lot of energy, that is, would be fighting the huge latent heat of evaporation again? And I would wonder just why bothering to desalinate the water?

deleted 14y ago
[deleted]
chii 14y ago
> And I would wonder just why bothering to desalinate the water? perhaps it sucks to have salt deposits due to the evaporation?
- chroem 14y ago
  One word: corrosion. I honestly don't think this idea is too far fetched, though it's going to need subsidies to get going. If it all works out, then it would be pretty revolutionary.
- graycat 14y ago
  Sure, but's got to be much cheaper to scrape off and shovel out the salt than to separate it by reverse osmosis, etc. Besides, to save on the scraping, might line the relevant areas with some tough, flexible plastic and, then, periodically shut down, remove the plastic, flex it to break off the salt, reinstall, and continue.

brc 14y ago

EROEI will kill this thing stone dead, if the world is still thinking rationally. Note that it is essentially a solar installation, it doesn't really say if it works during the night. But you can safely assume that if it works on temperature, the headline 'nameplate' figure of 500 gw is only available in peak conditions. It says it uses desalinated water - which is a very energy intensive operation- so at best I figure it would be mildly energy-neutral, at worst it would actually be an energy suck. Then there is the small matter of all the embedded energy in the worlds second tallest structure. The costs are $1 billion for the tower, $100 million for the pipeline, and desal plants are about a $1b a piece these days. That's $2.1 billion invested - not including transmission lines - that's going to take a very long time to earn back. It looks like a subsidy farming exercise to me, or possibly a stock pump'n'dump scheme.

richardjordan 14y ago
Any time people think in terms of EROEI they get an upvote from me, as it's the problem with so many plans. I was hoping from the headline that this was a conc. solar tower or something similar, as have been described in the past and which have a chance of being EROEI positive. Sadly few people see the world in the eyes of basic physics and energy return on energy investment. Most of the utopians who believe we'll think ourselves out of the energy crisis without having to make any lifestyle changes or depopulate tend to rely on arguments that are almost always EROEI negative.

fernly 14y ago

"Solar Wind Energy has said... that each tower would require a permanent workforce of 1,000 people." Doing what, exactly? That has to be a bogus number.

Cryode 14y ago

What a giant eye sore.

gavanwoolery 14y ago

Is it wrong that the first thing I thought of was this: http://majorslack.com/pics/screenshots/redalert_03.jpg http://majorslack.com/pics/screenshots/redalert_03.jpg ?

deleted 14y ago

[deleted]