The fraction of potential realized by farms in an unrestricted channel for both examples when we add turbines is depicted in figure 15(a,b). The figure shows three tuning strategies, optimal concert tuning, optimal turbine tuning considering a single row in the canal, and Lanchester-Betz tuning. The thick lines are for ϵ=0.25 and the thin lines are for ϵ=0.1. It can be observed that there are larger differences between the tunings after realizing 50% of the potential for both turbine densities, with the concert tunings giving the best results. The shallow channel also quickly realizes the potential for fewer lines than the tidal strait. Going further, the differences between optimization strategies are larger for moderate turbine densities than for small-density ones. Figure 15 (a,b): Change in farm efficiency with three optimization strategies when turbines are added to a farm in an unconstricted canal. The concatenated dashed curves represent the optimal Lanchester-Betz tuning, r_3=1/3. The solid curves are for optimal tunings during concerts and the dotted curves are for optimal turbine tunings when only a single line, OSTRA, is tuned. Adapted from [5]Figure 16: Effect on (a) farm efficiency and (b) flow reduction by adding rows of turbines to an optimized farm occupying 20% ​​of the cross section. Solid curves refer to shallow channels while dashed curves refer to tidal straits. Adapted from [7]For optimal tunings during concerts, tunings increase as rows are added due to sharing the load from a finite source across multiple rows, although there is diminishing return from new rows. In the other two optimization strategies, the available power peaks and further decreases as files are added. Therefore tunings are necessary during the concert... half of the paper... the cross section would be proportional to the product of the density of the fluid and the cube of the velocity of the flow, which makes the current of water at a given velocity, as effective as the wind current with a speed 9.5 times higher. The force on the turbines is proportional to the density of the fluid multiplied by the square of the flow velocity. So, for a tidal turbine that produces the same power as the wind turbine, the force on the current turbine is greater than that of the wind turbine based on the ratio of their speeds. Turbines require additional support structures for installation. The drag force on these structures due to flow reduces flow without generating energy. If the force on the turbines is F_T and the force on the support structures is F_S, the calculated available power will be reduced by a factor F_T⁄((F_T+F_S)). This will result in a significant reduction in available power.