Final answer:
It is false that hydroelectric power can replace depleted coal reserves on its own. Hydroelectric power has geographical and environmental limitations and only addresses part of our energy needs.
Step-by-step explanation:
The statement that we can replace depleted coal reserves by increasing our output of hydroelectric power is false. While hydroelectric power is a clean and reliable source of energy, its potential for expansion is limited by geographical and environmental factors. Hydropower is unlikely to provide a wholesale replacement for fossil fuels due to its limited scale and the fact that it only provides electricity, rather than addressing the wide array of energy needs currently met by coal, such as heating and transportation. In addition, there are environmental impacts associated with hydropower, such as disruption of fish migration and ecosystem changes caused by dams. The transition from fossil fuels like coal to renewable sources of energy requires a diverse portfolio of energy solutions, including not just hydroelectric but also solar, wind, nuclear, and others, as well as an overall reduction in energy consumption.