4 ms·

I think you are forgetting about the environmental impact of hydro damns. It floods entire valleys, displaces lots of flora and fauna and it uses much more conc

by jcfrei 5y ago

I think you are forgetting about the environmental impact of hydro damns. It floods entire valleys, displaces lots of flora and fauna and it uses much more concrete than wind farms.

oneoff786 5y ago
The advantage of hydro is that you can turn it on whenever you want. Environmental impacts aside, wind will never have that.
- vidarh 5y ago
  Except when the reservoirs run dry, which many will do at times unless you spend only a rather small proportion of the available capacity. Norway is a huge energy exporter, but regularly imports because of reduced hydro generating capacity. Expanding storage capacity is generally a problem because of the massive environmental impact.
  - pas 5y ago
    > Expanding storage capacity is generally a problem because of the massive environmental impact Meh. It could be put completely underground. (We could put nuclear power plants hundreds of meters deep underground too.) People don't want to spend on it is the real problem.
  - goodcanadian 5y ago
    Norway is a huge energy exporter, but regularly imports because of reduced hydro generating capacity. I have recently come to the conclusion that hydro is a very good complement to wind because the hydro is dispatchable when the wind doesn't blow. As long as the average wind and hydro together exceed needed capacity, things should be good. As I understand it, this is what Norway is doing. Importing wind from Germany when there is excess and exporting hydro when there is a shortage.
    - otherme123 5y ago
      A similar dynamic between Spain and France: Spain sells wind to France, France sells nuclear to Spain.
    - vidarh 5y ago
      Yes, and when you have already paid the environmental cost of hydro, it's a good tradeoff. If you need to destroy new large parts of your ecology and display people, it's a much trickier decision. I'm not fundamentally opposed to hydro including building new dams, but it's important people are aware that they have both massive ecological and humanitarian challenges, and create a long term maintenance commitment (or they become potentially disastrous) that means they're not no brainers. When they're still a decent fit, they're then absolutely a good complement to other renewable resources.
  - oneoff786 5y ago
    That’s not really a counterpoint. That hydro isn’t an infinite source of energy isn’t remarkable.
    - vidarh 5y ago
      The point is not that it isn't infinite, but that you can't rely on it always being available, just as with wind or solar. You still need fallbacks unless you over dimension massively, and over dimensioning hydro storage comes with massive ecological impact.
- otherme123 5y ago
  Energy is a grid. As long as you have wind and FV, hydro is accumulating water for less windy/sunny moments. We tend to look at batteries as something that has to be physically linked (the wind mill must reverse a hydro or must store in a lithium battery), but it can be though as avoiding to release the water in the first place. Viewing the different technologies on the grid as isolated competitors in which one must "win" over the others as if they were Walmart vs Costco is a mistake. E.g. nuclear providing 20-30% of the load is a must, but providing more than 60% is a drag. The trick is to get, slowly evolving, a good mix in the grid that is reasonably cheap and green (wind and solar) and reasonably stable (nuclear, hydro and gas). Too cheap and you get blackouts. Too stable and you get high prices and CO2.
sschueller 5y ago
I am aware but as a total I find that impact to be minor especially if great care it taken to determine where such a damn is built.
- vidarh 5y ago
  There aren't many places to build hydro left where the impact would be low. The typical environmental impact tends to be huge and the number of people displaced tends to be huge, because the type of places most suitable to build up also tends to be the types of places that have historically attracted human settlements. On top of that, the ongoing release of e.g. methane for years after construction coupled with the environmental cost of the construction materials means it takes a long time for dams to even pay off the environmental debt they create. The death toll from hydro is also not all that reassuring. Even if you subtract the Ban Qiao dam failure, the single most destructive power plant failure in history[1], beating e.g. Chernobyl several times over, construction accidents and the like adds up, and contributes to a lasting maintenance burden where guaranteeing sufficient maintenance becomes a growing risk to downstream downstream populations for as long as the dams exist. I'm sure there are places where dams are still reasonable choices, but they're no unambiguously good choices. [1] https://en.wikipedia.org/wiki/1975_Banqiao_Dam_failure https://en.wikipedia.org/wiki/1975_Banqiao_Dam_failure

by jcfrei 5y ago

I think you are forgetting about the environmental impact of hydro damns. It floods entire valleys, displaces lots of flora and fauna and it uses much more concrete than wind farms.

oneoff786 5y ago

The advantage of hydro is that you can turn it on whenever you want. Environmental impacts aside, wind will never have that.

vidarh 5y ago
Except when the reservoirs run dry, which many will do at times unless you spend only a rather small proportion of the available capacity. Norway is a huge energy exporter, but regularly imports because of reduced hydro generating capacity. Expanding storage capacity is generally a problem because of the massive environmental impact.
- pas 5y ago
  > Expanding storage capacity is generally a problem because of the massive environmental impact Meh. It could be put completely underground. (We could put nuclear power plants hundreds of meters deep underground too.) People don't want to spend on it is the real problem.
- goodcanadian 5y ago
  Norway is a huge energy exporter, but regularly imports because of reduced hydro generating capacity. I have recently come to the conclusion that hydro is a very good complement to wind because the hydro is dispatchable when the wind doesn't blow. As long as the average wind and hydro together exceed needed capacity, things should be good. As I understand it, this is what Norway is doing. Importing wind from Germany when there is excess and exporting hydro when there is a shortage.
  - otherme123 5y ago
    A similar dynamic between Spain and France: Spain sells wind to France, France sells nuclear to Spain.
  - vidarh 5y ago
    Yes, and when you have already paid the environmental cost of hydro, it's a good tradeoff. If you need to destroy new large parts of your ecology and display people, it's a much trickier decision. I'm not fundamentally opposed to hydro including building new dams, but it's important people are aware that they have both massive ecological and humanitarian challenges, and create a long term maintenance commitment (or they become potentially disastrous) that means they're not no brainers. When they're still a decent fit, they're then absolutely a good complement to other renewable resources.
- oneoff786 5y ago
  That’s not really a counterpoint. That hydro isn’t an infinite source of energy isn’t remarkable.
  - vidarh 5y ago
    The point is not that it isn't infinite, but that you can't rely on it always being available, just as with wind or solar. You still need fallbacks unless you over dimension massively, and over dimensioning hydro storage comes with massive ecological impact.
otherme123 5y ago
Energy is a grid. As long as you have wind and FV, hydro is accumulating water for less windy/sunny moments. We tend to look at batteries as something that has to be physically linked (the wind mill must reverse a hydro or must store in a lithium battery), but it can be though as avoiding to release the water in the first place. Viewing the different technologies on the grid as isolated competitors in which one must "win" over the others as if they were Walmart vs Costco is a mistake. E.g. nuclear providing 20-30% of the load is a must, but providing more than 60% is a drag. The trick is to get, slowly evolving, a good mix in the grid that is reasonably cheap and green (wind and solar) and reasonably stable (nuclear, hydro and gas). Too cheap and you get blackouts. Too stable and you get high prices and CO2.

sschueller 5y ago

I am aware but as a total I find that impact to be minor especially if great care it taken to determine where such a damn is built.

vidarh 5y ago
There aren't many places to build hydro left where the impact would be low. The typical environmental impact tends to be huge and the number of people displaced tends to be huge, because the type of places most suitable to build up also tends to be the types of places that have historically attracted human settlements. On top of that, the ongoing release of e.g. methane for years after construction coupled with the environmental cost of the construction materials means it takes a long time for dams to even pay off the environmental debt they create. The death toll from hydro is also not all that reassuring. Even if you subtract the Ban Qiao dam failure, the single most destructive power plant failure in history[1], beating e.g. Chernobyl several times over, construction accidents and the like adds up, and contributes to a lasting maintenance burden where guaranteeing sufficient maintenance becomes a growing risk to downstream downstream populations for as long as the dams exist. I'm sure there are places where dams are still reasonable choices, but they're no unambiguously good choices. [1] https://en.wikipedia.org/wiki/1975_Banqiao_Dam_failure https://en.wikipedia.org/wiki/1975_Banqiao_Dam_failure