[HN Gopher] In a major reversal, the world bank is backing mega ...
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       In a major reversal, the world bank is backing mega dams (2024)
        
       Author : prmph
       Score  : 29 points
       Date   : 2025-07-21 20:48 UTC (2 hours ago)
        
 (HTM) web link (e360.yale.edu)
 (TXT) w3m dump (e360.yale.edu)
        
       | Ancalagon wrote:
       | Please can we just get back to building nuclear
        
         | bryanlarsen wrote:
         | $80B is buying 40MW of hydro. What would that get you for
         | nuclear? 4MW?
        
           | ginko wrote:
           | It's 40GW of hydro
        
           | jasonwatkinspdx wrote:
           | If we use Vogtle as a cost benchmark you'd get roughly 5 GW
           | (note you typo'd units to MW).
        
             | erentz wrote:
             | Given these projects will be overseas we shouldn't use the
             | extreme outlier of Vogtle in the US as the benchmark.
        
           | qwe----3 wrote:
           | Looks like at least 30GW
           | 
           | https://www.reuters.com/sustainability/boards-policy-
           | regulat...
        
         | daymanstep wrote:
         | There is a finite amount of hydro in the world. They will run
         | out of viable dam locations pretty quickly at this rate.
        
           | Animats wrote:
           | All the good sites were used by 1940.
           | 
           | The ideal big dam is Hoover Dam. Large, deep canyon in a
           | desert. Narrow, deep canyon dam site. Hard rock geology. No
           | major towns or agricultural areas in the area to be flooded
           | above the dam. That's the best case.
           | 
           | Most later dams are at worse sites.
        
             | tomrod wrote:
             | In which continent?
        
         | marcosdumay wrote:
         | Make nuclear cost-competitive and people will start building
         | it.
        
           | notepad0x90 wrote:
           | I thought it was cost-competitive with something on the scale
           | of mega-dams and takes about as long to finish too. Except
           | unlike dams, you don't disrupt river flow and cause water-
           | rights disputes (and potentially wars).
        
             | janice1999 wrote:
             | > Except unlike dams, you don't disrupt river flow and
             | cause water-rights disputes (and potentially wars).
             | 
             | The water requirements of nuclear power stations cooling
             | systems can cause significant issues. The discharge of
             | heated water back into rivers and the sea is also a major
             | problem.
        
               | tomrod wrote:
               | How major? Would not a temporary lake be sufficient to
               | dissipate heat?
        
             | marcosdumay wrote:
             | The unit economics of dams get more and more competitive
             | when their size increase.
             | 
             | So, hell no, nuclear is not competitive with mega-dams.
             | It's not even competitive with small dams.
        
           | colechristensen wrote:
           | Nuclear is cost competitive if you have a reliable cadence of
           | building plants and if folks get out of the way of location
           | permits and waste storage and people can actually make
           | decisions about them without endless debates and lawsuits.
           | The problem is one-off designs and the decades long gap
           | between project inception and when investment returns start
           | coming in. As opposed to solar where I could order a few
           | panels and accessories online and start producing energy
           | within a week. Obviously larger solar projects take more
           | planning but if you've got a roof, a credit card, and an
           | electrician on hand you can start producing electricity or
           | expand your production in a very short time achieving break
           | even in a few years.
        
         | V__ wrote:
         | Nuclear just isn't economically viable. Maybe fusion someday.
        
           | qwe----3 wrote:
           | Tell that to China
        
             | bobthepanda wrote:
             | China has been building them at a relatively lukewarm pace
             | compared to its solar and wind expansion
             | 
             | > China installed 1GW of nuclear last year, compared to
             | 300GW of solar and wind, Mr Buckley said.
             | 
             | https://www.abc.net.au/news/science/2024-07-16/chinas-
             | renewa...
        
           | forrestthewoods wrote:
           | > isn't economically viable
           | 
           | That is not an intrinsic truth. We have chosen to make it
           | economically unviable.
           | 
           | Most things get cheaper to build with time. Nuclear is an
           | outlier where it used to be affordable and now it isn't.
           | That's insane.
        
             | permo-w wrote:
             | why is it different like that?
        
             | bryanlarsen wrote:
             | Nuclear has never been particularly affordable. It's always
             | been more expensive than coal or gas, even in France in the
             | 70s-80s and China in the 2010s.
        
         | Kon5ole wrote:
         | The solar panels installed in China during the past 2 years
         | produce as much electricity as all of their nuclear plants
         | combined.
         | 
         | Finland spent 18 years and 11 bn euros to get 1.6 GW of
         | nuclear, the US spent 7bn in subsidies and got some 20 GW of
         | solar in 2022 alone.
         | 
         | Countries going for nuclear will wait decades to get the same
         | power that solar can add in weeks.
         | 
         | Nuclear basically makes no sense at all in 2025.
         | 
         | (For nighttime use dirt-cheap batteries and natural gas now,
         | even cheaper batteries and generated hydrogen gas later).
        
           | geysersam wrote:
           | But what to do in Finland during the winter months? I'm
           | massively pro solar, and I'm sceptical of nuclear, but this
           | seems like a problem to me. Batteries work well on shorter
           | time scales but not over the entire year.
        
       | brian-armstrong wrote:
       | Dammed if you do, damned if you don't
        
         | pyuser583 wrote:
         | Dam!
        
         | jeffrallen wrote:
         | No more dam jokes.
        
           | tomrod wrote:
           | This made me chuckle. Well done!
        
       | Rover222 wrote:
       | We have cheap fusion. A giant reactor in the sky. Solar should be
       | massively scaled, along with battery capacity and pumped storage.
       | China is crushing in this.
        
         | landl0rd wrote:
         | Hard agree on pumped hydro and other forms of grid-scale
         | storage, but can you understand concerns around batteries?
         | There are environmental ones on the mining/metals side, but
         | producing and disposing of them in a clean manner is often
         | hard. Getting them from anywhere save mostly china is hard (if
         | you want large, dense, affordable, and grid-scale options) and
         | depending on somebody who's nobody's geopolitical friend is
         | probably a bad idea.
         | 
         | Ditto for the panels themselves.
        
         | bryanlarsen wrote:
         | Hydro is a great complement for solar, you can decrease flow
         | when the sun is shining, and increase it when it isn't.
        
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