I have been kicking around an idea for a while about generating electricity from ocean tides. The traditional approach is to use the flow of water through a channel to turn a turbine, which essentially blocks the channel for sea life and water craft. It seems more practical to use the rise and fall of the tide like a slow moving, yet powerful piston. The way I envision it, there would be a barge attached to posts set in the ocean floor. As the tide moved the barge, gears on the posts would turn a turbine on the barge. Say two complete turns of the piston occur every 24 hours. The height of the tide is 3 Meters. The weight of the barge is 1,500,000 kg. Assuming 100% of the energy could be converted into electricity, how much electricity could this device put into the grid? Thanks in advance for the help.