It is pretty good. It has a few other problems: * Can't be built in lots of areas due to geography * Struggles seriously in droughts * Large reservoirs emits

It is pretty good. It has a few other problems: * Can't be built in lots of areas due to geography * Struggles seriously in droughts * Large reservoirs emits significant biogenic methane (especially in warm areas) [1], which is a powerful greenhouse gas * Messes with fish * Gets scary in major rainfalls [1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5023102/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5023102/