Tuesday, January 23, 2007

Enviro impacts of in-stream tidal energy

I've been searching everywhere for comprehensive environmental impact assessments of in-stream tidal energy. I guess because there haven't been any major in-stream tidal energy projects, there also isn't much available in the way of research results.

The environmental and societal impacts of the old style tidal barrage (think: dam) have been well documented: significant damage to estuarine ecosystems including destruction of habitat for fish, bird and other organisms, disruptions to commerical & recreational navigation, as well as significant alterations to river currents & sediments.

It appears that these factors would not come into play where in-stream tidal energy is concerned. Why?
1. in-stream turbines are located individually underwater, therefore no dam blocking the flow of water,
2. small marine life can pass through the slow turning blades (larger creatures are diverted by screens on some turbines),
3. early simulation appears to indicate that in-stream turbines (because they are capturing only a portion of the energy of the current) will not cause silt build up or significant alterations to marine currents.
If this is the case then in-stream tidal energy would be the greenest of the alternate energy technologies!

4 comments:

Unknown said...

Terry, I just learned about the proposed increase in strip mining up in Hants West around Windsor/Hantsport, and thought you might want to know about it too, if you don't already. I'm worried, and trying to figure what I might do to help, other than posting info on my own blog.

You can read about the situation affecting the Avon River Watershed at www.avondalemedia.ca/APWPS.

cheers, jodi

Ralph Smith said...

Hi Terri

Glad to find your blog, especially the series on "tidal energy". Interesting to me since I grew up on the Bay of Fundy and have heard a lot of talk about harnessing the tide. The concept drawings are enthralling by themselves, never mind the reality to come. Thanks for keeping us posted.

Cheers

Terri said...

thanks for the comments you two. I think there is great potential for developing environmentally sustainable projects in the Bay region. Perhaps tidal energy will be that, perhaps not but I certainly plan to keep an eye on new developments from my vantage point here in Parrsboro...Terri

Tom Allan said...

Hello Terri,

I'm doing some research about tidal energy myself, but in relation to the plans for a barrage across the Severn. I live in the South-West of England.

I was wondering if I could call or chat with you some time? I'd like to ask some questions about the Annapolis Royal Generating Station.

Best, Tom.

w_t_allan@yahoo.com