The cost of setting up a tidal power station can be very high, although once in place the operating costs are low. As an example of the cost of setting up, a proposed 8000 MW tidal power plant and barrage system on the Severn Estuary in the UK has been estimated to cost US$15 billion, while another in the San Bernadino strait which would produce 2,200 MW as a tidal fence in the Philippines will cost an estimated US$3 billion.

One area of concern is how underwater noise generated by the turbines could affect marine mammals that use auditory cues to navigate and communicate with each other.

Tidal power is a means of electricity generation achieved by capturing the energy contained in moving water mass due to tides. Two types of energy can be extracted: kinetic energy of currents between ebbing and surging, and potential energy from the difference in height (or head) between high and low water marks.

Tidal power schemes do not produce energy 24 hours a day. A conventional design, in any mode of operation, would produce power for 6 to 12 hours in every 24 and will not produce power at other times