Tidal power developments by British firms show this renewable power technology achieving impressive scale and continued design innovation. Bristol-based Marine Current Turbines (MCT) revealed last month that its SeaGen dual-turbine system achieved full power operation of 1.2 megawatts. MCT’s power peak is four times the global record for a tidal stream system set by the company in 2004, according to U.K.-based renewables journal REFocus, and 30-times more than the output from the tidal turbines pumping electricity in New York’s East River.
Meanwhile the U.K. Guardian reported yesterday that more largescale demonstrations are on the way as Cardiff-based Tidal Energy Ltd prepares to test a 1-MW version of its triple-rotor design by next year off the coast of Wales.
Achieving full power operation clears a major hurdle for MCT. As TechReview reported last July, the company suffered a setback early on when the powerful tidal streams of Northern Ireland’s Strangford Lough damaged one of its blades shortly after installation. In an odd way it’s an affirmation of MCT’s design, which enables the dual rotors to be lifted clear up out of the water for easy maintenance and repair.
While at a considerably earlier phase of development, MCT rival Tidal Energy’s triple-rotor concept provides an equally innovative means of ready repair. Tidal Energy’s rotors sit at the corners of a three-legged platform that can be deposited on the seabed and held in place by the systems 250-ton heft. That should not only ease recovery of the system for maintenance, but also simplify installation by eliminating the need for a fixed foundation in the seabed.
To see these concepts in action see MCT and Tidal Energy’s dueling animations.
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This post was created for the Technology Review guest blog: Insights, opinions and analysis of the latest in emerging technologies
Peter Fairley 
Where can i find a histogram of the worlds energy usage broken down by type of energy technology? And is the same histogram available as projections, near term and far term? Is the same histogram also available for past dates? And is it possible to see some longer term trends analogous to Moore’s law? Is the tidal wind farm a possibility? And would that technology be expected to ramp-up quicker given the previous aeronautical wind farm experience?
Gerard
I come across such histograms from time to time and will try to dig some up. Perhaps you could do a Google search or two and post what you find?
Regarding your questions about the development path of tidal power, its similarities to wind power certainly help. In a 2007 story for Technology Review I reported found that:
As for the potential impact of tidal energy, here are some useful comments from British authorities aggregated by the British Wind Energy Association:
I did a search on “world energy usage” and got some useful sites. However i liked the following URL at BP: http://www.bp.com/sectiongenericarticle.do?categoryId=9023766&contentId=7044197 because it had an Excel dataset that you could download with many different types of data. To make best use of this requires installing the histogram capability into Excel (this is easy to do just go to help in Excel). I get for example for the total world energy use binned by energy use:
Bin Frequency
0 0
1000 0
2000 0
3000 0
4000 1
5000 5
6000 5
7000 9
8000 4
9000 10
10000 5
more 4
This has an interesting behavior when we consider that energy usage has an approximately linear (found by graphing the dataset)increase over time. But apparently the usage lately has bucked that trend and energy usage is now increasing more than average.
Gerard
Thanks for that resource Gerard. We just need to be careful to check the fine print. In trying to figure out where renewables fit in to that BP data, I discovered the following footnote: “In this Review, primary energy comprises commercially traded fuels only. Excluded, therefore, are fuels such as wood, peat and animal waste which, though important in many countries, are unreliably documented in terms of consumption statistics. Also excluded are wind, geothermal and solar power generation.”
I don’t buy either point. First off, there are major questions about the numbers for natural gas and oil. For example, disputes over how much natural gas Russia ships to Ukraine and how much Ukraine extracts before shipping it south to Europe is at the heart of the recurring natural gas supply disruptions afflicting Europe.
As for excluding wind, geothermal and solar power generation: Why does BP include hydropower in its data if it is then going to exclude other sources of renewable electricity?
An alternative source if you really want to dig into data is the U.S. Department of Energy’s Energy Information Agency website, which is a data goldmine. See the World Energy Overview for one starting point. Note that the EIA overview’s Table 2.9 on world primary energy production presents renewables other than hydro as a separate category.
Right. We have to be careful apparently about what energy websites are/aren’t including in their data. However, initially I was not trying to necessarily include all energies rather I was just trying out some of the ‘goods’.
I tried that EIA site and was able to make some interesting graphs with the Excel data they provide. I think they answer many of the trend questions I had asked.
Thanks for pointing me to that site.