6. Costs and deadlines

The cost of plants (including civil engineering) operating in both directions with a mean tidal range H of 5 to 8 m is probably in the order of e1,000 to e1,500/kW for a use equivalent to 3,000 h at full power. Plant investment per kW per year is therefore 0.3 to 0.5 e (Russian projects are approaching 4,000 h/year).

The economic impact of dikes varies essentially with the length of dike per km ² of basin, whose annual production in GWh is of the order of 0.7 H ² (25 GWh for 6 m). For a dike cost of e3,000/m ² , i.e. e75,000/m and a dike length of 200 m per km...