Flow resources: water, wind and sunlight are neither renewable nor non-renewable because they can only be used when and where they are. The energy in a river can be used to generate electricity, but it must be captured by turbines or it will be lost.
A: A flow resource is a resource that there is a certain amount of on Earth. Water is not renewable because renewable is a resource that you use up and reproduce. You can not produce water, you just clean it and reuse it. Tidal power is water power so it is not renewable.
