Wave resource in UK

Nowadays we are enjoying great news even coming from mass media about the huge potential and possibilities of wave and tidal sector. Guardian published early this year "UK could become leading exporter of wave and tidal power, say MPs" based on a report from Energy and Climate Change Committee calling on government to establish long term goals for marine energy to give guarantees and estability for further industrial developments.

WAVES

But, what is the real potential of waves? There are several studies trying to bring light to this issue. Independently of which one you read, all of them assure a potential far beyond our electrical energy consumption even highlighting that the wave global power potential is estimated to be around 8,000-80,000TWh/y (1-10TW), which is the same order of magnitude as world electrical energy consumption.

Evidently, not all the spots has the same potential. Best spots are found between 30-60 degrees latitude with a potential of 20-70 kW/m because the strong storms there. But for 30 degrees latitude there is a good choice when the waves come from regular wind blowing. Even with a less energy/potential, these places has an advantage over the first ones because the variability is reduced as well, which means generate electricity in a more regular basis and, maybe, reduce the mechanical efforts suffered by the devices.

UK

It is expected that marine energy could provide up to 27GW of capacity in the UK by 2050, much of which is expected to be deployed after 2020...but it will not become real if there isn't a real support from the Government today.

In 2008 the Department of Energy and Climate Change [DECC] published an online interactive webGIS version of the UK Marine Renewable Energy Resources Atlas with the clue of the highest potential spots.

The most conservative studies estimate the accesible potential around 50 TWh/y mainly situated off the northwest coast of Scotland and the seas of the southwest of England. This potential represents 12.4% of UK electricity generation, demanding the commercial development of the industry which both will lead to a cost decrease and will help in the path to become UK a leader in this area...but if there is a industrial development, the potential resource technically available could be much higher, as the wind industry development has demonstrated.

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  online interactive webGIS version of the UK Marine Renewable Energy Resources Atlas

  
  


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  Wave resource map

  
  

Image: Annual Mean Wave Height Crown ©2004

How do you like to do it: Horizontal or Vertical?

Tidal stream has a similar behaviour to wind as it is a fluid as well. So it has been relatively easy for engineering to transfer the concept of 3-bladed horizontal axis design to this new environment. Engineers argue that if it works with onshore and offshore air streams, being even the icon of clean energy and sustainability, why shouldn't it work with water streams?

It's pretty sure it will work. No doubt about engineering abilities on horizontal axis wind turbines. Yet we are talking about hydrodynamics and not aerodynamics,  the question should be: is this the best design we can achieve?

Recently I have read an interesting paper from Stephen Salter called "Are Nearly all Tidal Stream Turbines Designs Wrong?" which was presented during the Oxford Tidal Energy Workshop, held in Oxford during 29-30th March.

The aim of this paper is, in words of the author,  "to show that, despite its widespread popularity, the transfer from wind technology is wrong and that a cross-flow design with rotation about a vertical axis is better. "

3-bladed horizontal axis wind turbines are "universal" as everybody, including industry, investors, public, mass media and politicians assume it as the best choice in this area.

But if a company achieves a better design in terms of efficiency, cost reduction, installation and O&M in tidal/ocean streams using a vertical axis design [don'tforget it is a completely different environment] there will be a major question to answer:

* Will this company achieve a leadership position in the industry and get the confidence of the investors?

I guess this issue can be one of the main topics for the next as the technology is developing faster than expected and I hope to get a further understanding of the different possibilities of the designs.

Photo from Marine Current Resource and Technology Methodology

Wave Roller - Peniche [Portugal]

httpv://www.youtube.com/watch?v=DfD7XthBbWA&feature=colike

2:17 report in TVI 24: Peniche: produzir energia através das ondas [Portuguese]

Teahupoo - Tahitian wave

This is one of the world's most feared wave among surfers. It has an extreme violence and some surfers have died while trying to surf it. Just a little show what oceans are able to do.
httpv://www.youtube.com/watch?v=pA4ZLpV7BpQ

From windmills to energy parks

httpv://www.youtube.com/watch?v=ibaOWvMWzjM&feature=colike

Breve historia de combustibles fósiles

Un interesante y atractivo vídeo con una breve historia de los combustibles fósiles. Creo que las conclusiones finales son cruciales: no hay tiempo que perder porque el cambio se va a producir. La pregunta es ¿podremos gestionar el cambio o nos veremos desbordados?

httpv://www.youtube.com/watch?v=H7cbTbo0RaY&feature=share

Intermitencia de renovables

Interesante artículo escrito por James Tipping y Duncan Sinclair: "Marine energy can balance intermittency of renewables". Es una entrada un tanto antigua pero muy actual por el debate no cerrado sobre las interferencias en el sistema eléctrico generado por las intermitencias de las energías renovables, principalmente en UK.

El motivo de este debate estriba en a medida que aumenta la aportación de las energías renovables, su variabilidad en producción, basada principalmente en energía eólica y solar, tiene un impacto significativo en la garantía de suministro y, por tanto, en el mercado eléctrico. Los autores basan su defensa en los enormes beneficios que genera la diversificación de un mix y la importancia de la energía de las olas en "garantizar la estabilidad" de la producción eólica dado que puede prever su producción. Desafortunadamente, no han contemplado la energía de las mareas como posibilidad, quizá porque su estadio de desarrollo todavía es demasiado incipiente.

Interesantes conclusiones como que un mix diversificado con mayor penetración de renovables podría reducir más de un 3% el coste de la electricidad. Incluso comentan que los ahorros podrían ser superiores con la implementación de un correcta gestión de las redes y gestionando la demanda ( parte de las redes inteligentes)

Aunque su conclusión final es que las tecnologías marinas pueden complementar a la eólica, aumentando la efectividad y permitiendo una expansión del conjunto de todas las renovables en el mix de generación eléctrica.