This method of operation utilizes both flood and ebb phases of the tide to
generate electricity. The sluice gates and turbines are kept closed until near the end of the flood cycle.
After this point the water is allowed to flow through the turbines, generating electricity. When the
minimum hydrostatic head for generating electricity is reached the sluice gates are then opened. At
high tide, the sluice gates are closed and the water is trapped behind the barrage until a sufficient
hydrostatic head is reached once again. Water is then allowed to flow through the turbines to generate in
the ebb mode. Two-way generation has the advantage of a reduced period of non-generation and a
reduction in the cost of generators due to lower peak power