Primer on the technologies of renewable energy

The difference between the two lies in the scale of the projects and the amount of electricity produced. [...] Despite the differences in definition, the important environmental distinction for hydroelectric plants is not the size of the project, but instead the potential local and cumulative effects of waterpower facilities on the environment. [...] Once the tide is out, the water is allowed to flow through holes near the bottom of the barrage where the turbine is located. [...] As a wave enters the column, it forces the air in the column up the closed column past a turbine, and increases the pressure within the column. [...] Parabola — The wave enters the parabola, which focuses the wave, increasing its height and the pressure the water exerts on the air in the column.