The Environment Agency has identified 2,300 sites within rivers in the North West where small-scale hydroelectric turbines could be installed to power 140,000 homes.
According to a study by the Environment Agency, it found turbines could be installed at the locations to generate electricity from the water without damaging wildlife in rivers around the region.
The study said there were 58 potential win-wins within the North West, representing 23% of the power potential, where a hydropower scheme with a fish pass could deliver an improvement in the local environment as well as renewable electricity.
Within the UK, almost 26,000 locations have been identified where small-scale hydroelectric turbines could be installed to power 850,000 homes.
Its study said the turbines could produce 1.5% of the UK's electricity needs, but not all of the sites are viable for development due to difficulty accessing the local electricity grid.
Tony Grayling, head of climate change and sustainable development at the Environment Agency, said: "Some hydropower schemes have the potential to deliver low carbon electricity and improve the local environment for wildlife, for example by improving fish migration. But there will inevitably be some sites where the risk to the environment outweighs the benefits of power generation."
The study said around half the sites in the UK would need fish-friendly measures such as screens to stop fish getting killed by turbines.
The Environment Agency estimates that a medium-sized scheme, costing £100,000 to £150,000 to set up and providing enough electricity to power 32 homes, could receive around £25,000 a year in funding.