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New studies are showing that hydro is not as clean as we once thought and may be producing large amounts of methane (due to anaerobic breakdown of organic mater
by twojacobtwo 5y ago
New studies are showing that hydro is not as clean as we once thought and may be producing large amounts of methane (due to anaerobic breakdown of organic materials in flood basins), which is orders of magnitude worse than CO2 per unit volume for greenhouse effects in the short-to-medium term.
- Retric 5y agoThat’s missing the wider context, organic matter breaking down in rivers and estuaries also produces methane. https://pubmed.ncbi.nlm.nih.gov/20390897/ https://pubmed.ncbi.nlm.nih.gov/20390897/ Dams net climate change impact is very close to zero.
- twojacobtwo 5y agoThe fact that a problem already exists in nature does not justify further exacerbating the problem. Their net climate change impact can only be considered close to zero when considered as offset fossil-fuel based sources. If they're emitting large amounts of methane and CO2 (until we get net 0 concrete), it seems extremely unlikely that the impact is close to 0.
- Retric 5y agoThey don’t make it worse because dams aren’t generating organic matter. Organic matter that falls into rivers is going to break down either way, and in a free flowing river it’s often going to break down where the water slows down in estuaries. Essentially you need to subtract the methane that would have been produced in other locations. In terms of concrete, the percentage of concrete produced worldwide that ends up in dams is minuscule. Only 34 states even have any hydroelectric dams. The US alone is producing 90 million metric tons per year, look for the most recent large hydroelectric dam in the US it wasn’t produced in 2021, or 2020, or 2019, or …