Last year, Canada dropped some experimental tidal turbines in the Minas passage of the Bay of Fundy. I remember reading about the sheer force and magnitude of the tidal movement in the Bay of Fundy and the desire to harness this wellspring of energy as a power source.
Turns out the rather conventional turbines were destroyed due to underestimating those tidal forces, unfortunately. Just last month, though, Ocean Renewable Power Company, deployed a spiral-ribbon turbine design off of Maine’s coast with the same purpose in mind. It is now delivering power to Maine’s power grid!
America’s First Ocean Energy Delivered to the Grid
September 13, 2012
Portland, ME, September 13, 2012 – Bangor Hydro Electric Company verified today that electricity is being delivered to their power grid from Ocean Renewable Power Company’s (ORPC’s) Cobscook Bay Tidal Energy Project. This is the first power from any ocean energy project including offshore wind, wave and tidal, to be delivered to an electric utility grid in the United States, and it is the only ocean energy project, other than one using a dam, that delivers power to a utility grid anywhere in North, Central and South America. This achievement is being hailed around the globe.
On a related note, I’ve always (since I saw the design in middle school) thought that using either a giant parabolic mirror or array of mirrors to focus solar energy onto a water source to generate steam is the best energy source. It’s fairly clean, even considering the manufacturing of the parts involved, unlike photovoltaic panels which if I recall correctly are still considerably dirty to manufacture. Just get a motor to spin with steam. I don’t have any factual basis (YET) for this, though.
There’s definitely a lot of thought going into solar->mirror->steam power generation, as evidenced by this citation and link-dense reddit commentary. Stirling Energy Systems in particular seems to be at the forefront. Much of the vitriolic invective by redditors seems to be over the initial capital investment of a scalable system on the gigawatt level, but it’s certainly a plus that the energy input is a free source, the sun. Stirling engines seem to work on heat exchanging.