Question

hydroelectric and coal - fired power plants produce electricity in a similar way. in both cases, an energy source is used to spin a turbine that will then generate electricity. the difference is that a coal - fired plant uses steam while the hydroelectric plant uses falling water to turn the blades of the turbine. which is not an environmental cost of hydroelectric power plants? flooding of upstream habitat near a dam disruption of the life cycle of salmon alters the natural flow of water downstream increased greenhouse gases being released

Explanation:

Hydroelectric power plants do not release greenhouse - gases during electricity generation. Flooding of upstream habitat, disruption of salmon life - cycle and altering downstream water flow are environmental costs.

Answer:

increased greenhouse gases being released