4 ms·

I really want to like hydro but it has clear negative effects on ecology (namely fish). I am really hoping wind and solar don't affect local ecology as much.

HPsquared 3y ago
Layman's question: don't the reservoirs create a new habitat for fish? They'd be "artificial" in a way but eh, so is everything else. Or is the problem that they all get turned into fish pie in the turbine...
- voakbasda 3y ago
  River fish need different habitat than lake fish. And in many areas, migratory fish are impeded from reaching their spawning grounds. Fish ladders and other contrivances are a poor workaround for an unimpeded flow.
- nereye 3y ago
  One of the main issues is that dams tend to block access to the upstream spawning grounds for species such as Coho salmon. E.g. see https://www.reuters.com/world/us/save-salmon-us-approves-largest-dam-removal-history-2022-11-17/ https://www.reuters.com/world/us/save-salmon-us-approves-lar....
  - bilekas 3y ago
    Not sure how prevalent they are bit aren't fish ladders built with dams for this exact reason? https://www.sciencedirect.com/science/article/pii/S0925857416305936 https://www.sciencedirect.com/science/article/pii/S092585741...
    - burkaman 3y ago
      Yes, but it's very hard to get fish to use them. Some species are almost completely blocked even if there is a ladder.
    - bobthepanda 3y ago
      They don't work for many species. For example, one study found that 3% of American shad were able to use a fish ladder. https://e360.yale.edu/features/blocked_migration_fish_ladders_on_us_dams_are_not_effective https://e360.yale.edu/features/blocked_migration_fish_ladder... Fish ladders are akin to greenwashing.
    - belorn 3y ago
      Fish ladders are expensive and have a fairly large negative impact on yearly electric output. Forcing upgrades makes most dams too expensive, which would mean they get replaced by fossil fueled power plants which can more cheaply operate as backup for wind and solar. As a result, most hydro power in Europe is in direct violation of environmental laws, but are also given exceptions given the yearly and regular energy crisis.
- latchkey 3y ago
  Imagine in countries like Vietnam/Cambodia/Laos where they dam up rivers for hydro so badly that it prevents downstream flows, wiping out the downstream natural ecology. They also have wet/dry seasons, so for part of the year everything gets flooded, overruns the dams and wipes out whole villages. Pretty much a complete eco disaster that few talk about.
  - sdflhasjd 3y ago
    Is that for hydro or water storage though? Surely you want the flow for hydro.
    - latchkey 3y ago
      This isn't about storage. They build hydro dams on running rivers.
      - mdorazio 3y ago
        That’s not how it works. After it fills up you have to let water out of the dammed reservoir at the same rate it flows in (on average) or else it overflows. The issues created are related to sediments and flow consistency. More info in the top response here: https://earthscience.stackexchange.com/questions/18287/do-dams-reduce-the-flow-of-river-downstream https://earthscience.stackexchange.com/questions/18287/do-da...
        latchkey 3y ago
        I don't appreciate the downvote because you aren't listening to what I'm saying. When it rains, it floods. They (stupidly) build dams for rate of flow during low season (cause it isn't raining)... then the wet season comes and the dams all overflow. Poor construction practices doesn't help either. They also build dam after dam along the same river... I've see 10+ of these things... ends up being a chain of mess when the first one fails. Just a bit of googling to give you examples: "Dam design and greed may factor into flood devastation in Vietnam" https://www.refworld.org/docid/58f9ca0c13.html https://www.refworld.org/docid/58f9ca0c13.html https://tuoitrenews.vn/news/society/20231012/investigation-underway-for-broken-hydroelectric-dams-wall-in-vietnams-central-highlands/76126.html https://tuoitrenews.vn/news/society/20231012/investigation-u... https://www.voanews.com/a/vietnam-must-improve-flood-resilience-as-extreme-weather-hits-central-coast-say-experts/7331626.html https://www.voanews.com/a/vietnam-must-improve-flood-resilie...
- audunw 3y ago
  Look at pictures of a hydro power plant reservoir. Look at the water edge when the water level is lower. It’s like a desert. When the water level goes up and down it kills all life along the edge. That life is an important food source for fish.
  - m4rtink 3y ago
    That's pretty much how seasonal rivers work & other natural intermittent water reservoirs.
- gosub100 3y ago
  people already mentioned fish, but still water harbors bacteria and generally has lower oxygen levels than turbulent water. also nutrient-rich sediment piles up at the base of the dam instead of getting distributed evenly down the river.
lvspiff 3y ago
In NV it has really depended on the type of solar but seems anything that takes up large acres of land is going to be an issue. For ground based solar cell arrays we've had issues with the desert tortoise and other animals that it encroaches on their habitat. When you are using the molten salt method the bird population ends up at risk due to the laser like beam of light that gets directed towards the tower. They go so far as to deploy hawks and sounds but inevitably some bird brain gets fried.
- adventured 3y ago
  There is nothing of meaningful physical scale that can be built that doesn't encroach on some animals habitat. There are no exceptions, whether we're talking about a house, a road, a store, a factory, a power plant, a train line, a commercial office building. Humans only have two choices: de facto suicide, or encroach. I vote encroach.
  - dubcanada 3y ago
    There is plenty of desert and piles of garbage which are great for building solar panels on. Another aspect often overlooked is shade is very important, there are methods where building solar panels can actually help the environment by providing much needed shade. You can also build solar panels of the water, theoretically you could build solar panels suspended in the air. And they don't really require much to hold them down, compared to a wind turbine which needs to basically be a tree. We just don't try. There is no effort to experiment because everyone is scared to change.
    - nick222226 3y ago
      More like, because it's so damn hard to get reasonable rates paid for small developers solar projects power output?
foota 3y ago
Hydro is mostly (not entirely) tapped out for power generation (not, of course, for pumped storage, which doesn't require rivers). Creating reservoirs is also ecologically damaging, and releases a lot of methane (although I'm not sure how large the impact is relative to the carbon savings, this could be FUD I'm repeating)

HPsquared 3y ago

Layman's question: don't the reservoirs create a new habitat for fish? They'd be "artificial" in a way but eh, so is everything else. Or is the problem that they all get turned into fish pie in the turbine...

voakbasda 3y ago
River fish need different habitat than lake fish. And in many areas, migratory fish are impeded from reaching their spawning grounds. Fish ladders and other contrivances are a poor workaround for an unimpeded flow.
nereye 3y ago
One of the main issues is that dams tend to block access to the upstream spawning grounds for species such as Coho salmon. E.g. see https://www.reuters.com/world/us/save-salmon-us-approves-largest-dam-removal-history-2022-11-17/ https://www.reuters.com/world/us/save-salmon-us-approves-lar....
- bilekas 3y ago
  Not sure how prevalent they are bit aren't fish ladders built with dams for this exact reason? https://www.sciencedirect.com/science/article/pii/S0925857416305936 https://www.sciencedirect.com/science/article/pii/S092585741...
  - burkaman 3y ago
    Yes, but it's very hard to get fish to use them. Some species are almost completely blocked even if there is a ladder.
  - bobthepanda 3y ago
    They don't work for many species. For example, one study found that 3% of American shad were able to use a fish ladder. https://e360.yale.edu/features/blocked_migration_fish_ladders_on_us_dams_are_not_effective https://e360.yale.edu/features/blocked_migration_fish_ladder... Fish ladders are akin to greenwashing.
  - belorn 3y ago
    Fish ladders are expensive and have a fairly large negative impact on yearly electric output. Forcing upgrades makes most dams too expensive, which would mean they get replaced by fossil fueled power plants which can more cheaply operate as backup for wind and solar. As a result, most hydro power in Europe is in direct violation of environmental laws, but are also given exceptions given the yearly and regular energy crisis.
latchkey 3y ago
Imagine in countries like Vietnam/Cambodia/Laos where they dam up rivers for hydro so badly that it prevents downstream flows, wiping out the downstream natural ecology. They also have wet/dry seasons, so for part of the year everything gets flooded, overruns the dams and wipes out whole villages. Pretty much a complete eco disaster that few talk about.
- sdflhasjd 3y ago
  Is that for hydro or water storage though? Surely you want the flow for hydro.
  - latchkey 3y ago
    This isn't about storage. They build hydro dams on running rivers.
    - mdorazio 3y ago
      That’s not how it works. After it fills up you have to let water out of the dammed reservoir at the same rate it flows in (on average) or else it overflows. The issues created are related to sediments and flow consistency. More info in the top response here: https://earthscience.stackexchange.com/questions/18287/do-dams-reduce-the-flow-of-river-downstream https://earthscience.stackexchange.com/questions/18287/do-da...
      - latchkey 3y ago
        I don't appreciate the downvote because you aren't listening to what I'm saying. When it rains, it floods. They (stupidly) build dams for rate of flow during low season (cause it isn't raining)... then the wet season comes and the dams all overflow. Poor construction practices doesn't help either. They also build dam after dam along the same river... I've see 10+ of these things... ends up being a chain of mess when the first one fails. Just a bit of googling to give you examples: "Dam design and greed may factor into flood devastation in Vietnam" https://www.refworld.org/docid/58f9ca0c13.html https://www.refworld.org/docid/58f9ca0c13.html https://tuoitrenews.vn/news/society/20231012/investigation-underway-for-broken-hydroelectric-dams-wall-in-vietnams-central-highlands/76126.html https://tuoitrenews.vn/news/society/20231012/investigation-u... https://www.voanews.com/a/vietnam-must-improve-flood-resilience-as-extreme-weather-hits-central-coast-say-experts/7331626.html https://www.voanews.com/a/vietnam-must-improve-flood-resilie...
audunw 3y ago
Look at pictures of a hydro power plant reservoir. Look at the water edge when the water level is lower. It’s like a desert. When the water level goes up and down it kills all life along the edge. That life is an important food source for fish.
- m4rtink 3y ago
  That's pretty much how seasonal rivers work & other natural intermittent water reservoirs.
gosub100 3y ago
people already mentioned fish, but still water harbors bacteria and generally has lower oxygen levels than turbulent water. also nutrient-rich sediment piles up at the base of the dam instead of getting distributed evenly down the river.

lvspiff 3y ago

In NV it has really depended on the type of solar but seems anything that takes up large acres of land is going to be an issue. For ground based solar cell arrays we've had issues with the desert tortoise and other animals that it encroaches on their habitat. When you are using the molten salt method the bird population ends up at risk due to the laser like beam of light that gets directed towards the tower. They go so far as to deploy hawks and sounds but inevitably some bird brain gets fried.

adventured 3y ago
There is nothing of meaningful physical scale that can be built that doesn't encroach on some animals habitat. There are no exceptions, whether we're talking about a house, a road, a store, a factory, a power plant, a train line, a commercial office building. Humans only have two choices: de facto suicide, or encroach. I vote encroach.
- dubcanada 3y ago
  There is plenty of desert and piles of garbage which are great for building solar panels on. Another aspect often overlooked is shade is very important, there are methods where building solar panels can actually help the environment by providing much needed shade. You can also build solar panels of the water, theoretically you could build solar panels suspended in the air. And they don't really require much to hold them down, compared to a wind turbine which needs to basically be a tree. We just don't try. There is no effort to experiment because everyone is scared to change.
  - nick222226 3y ago
    More like, because it's so damn hard to get reasonable rates paid for small developers solar projects power output?

foota 3y ago

Hydro is mostly (not entirely) tapped out for power generation (not, of course, for pumped storage, which doesn't require rivers). Creating reservoirs is also ecologically damaging, and releases a lot of methane (although I'm not sure how large the impact is relative to the carbon savings, this could be FUD I'm repeating)