Harnessing energy from your greens

Maybe we could use a mangrove swamp or two and harness the energy from the plants on an incoming salt water tide.  Even better, plant a rabid greenie or two in the same fetid swamp.  Both are useless, one chokes our harbours, the other chokes our Parliament and airwaves.

Talking of useless, here in NZ this idea would probably never fly, as there's more than likely to a taniwha that needs its palm greasing with a bribe.