What is the potential for tidal power to supply carbon free energy to a world desperate to throw off the shackles of fossil fuels?

You would expect the potential to be huge because there are tides every where, right.

The answer may surprise you!

Tidal Power Turbine

This is a photo of the 1.2 megawatt tidal turbine installation at Strangford Lough, Northern Ireland, raised out of the water for maintenance. The world’s first commercial scale tidal turbine.

In service now since 2008, it supplies electricity to some 1000 homes.

At an installation cost of 8.5 million UK pounds ($12.75 at today’s rate), that’s a whopping $10.6 million per megawatt!

Compare this to the typical installation cost of a 2 megawatt onshore wind turbine of $3.5 million, that’s only $1.75 million per megawatt.

And the typical installation cost of an offshore wind turbine of $3 million per megawatt, although this will vary depending on the site.

*  *  *  *

Now we have the relevant costs, let’s go back to the potential of tidal power.

The total global energy in the tides is estimated at 3.5 terawatts, which sounds like a huge number, and is. But even as large as it is, this is only 20 percent  of total global energy usage.

But much of this occurrs in open oceans and is unusable, because to generate power efficiently the tidal current must have a speed of at least 1.2 meters per second. That leaves us with only 20 suitable sites world wide.

We are now reduced to a global potential less than 100 gigawatts.

That’s because currents of this speed are only present in certain shallow coastal waters.  However, due to the variability of the tides and the alterations to the tidal flow caused by the presence of the turbines, the potential is further reduced to only 10s of gigawatts.

Objections to tidal turbines has been growing, as an array of turbines across an estuary or channel, would substantially alter the marine ecology both up and downstream of the array.

However, Dr Graham Savidge of Queens University, Belfast has been monitoring the effects of the single turbine at Strangford Lough. He says,

“There has been very little impact really, it seems quite benign. However, when it started running we noticed passing Porpoises stopped communicating, but numbers have remained stable at the entrance and top of the lough.”

Perhaps this study will alleviate many of the worries of the objectors?

*  *  *  *

If you would allow a personal note, I have to admit to being a little sceptical as to the potential of tidal power. Is a return of 1000 homes equivalent electricity sufficient for an investment of £8.5 million?

I would think not in today’s financial climate.

The UK government’s energy minister Lord Hunt has just launched it’s ‘Marine Energy Action Plan’, when he suggested that the UK’s coastal waters had sufficient tidal and wave potential to supply 15 million homes.

He’s having a laugh! Does he expect us to believe him?

Taking the Strangford Lough example where the 1.2 megawatt turbine supplied 1000 homes, it would need 15,000 turbines to supply 15 million homes, at a cost of £12.75 million each!

Put another way, we would need 15,000 turbines at 1.2 megawatts, totaling 18,000 megawatts. That’s 55 gigawatts of tidal and wave power, which would exceed the global potential?

While we all should embrace clean technology as a replacement for fossil fuels, we have to be sensible with it. It is also advisable to keep political hype and falsehoods out of such a critical sector.

Sincerely,

P.S. Let me know what you think about tidal power and the clean energy debate in general, by leaving a comment or submitting a story through the link in the page menu.

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If Climate Change isn’t taking place then, this website, the world’s governments, hundred’s of NGOs, scores of scientists, and millions of people are wasting our time!

No action is necessary at all!

If that’s what you think, take a look at these two photos of Alaska from the US Geological Survey.

In a UK survey taken by Populus for the BBC during February 3 thro’ 4, 25% of people when asked…

‘From what you know and have heard, do you think that the Earth’s climate is changing and global warming taking place?’

…answered “NO.“

When asked this question…

‘Still thinking about climate change and global warming, based on however much or little you know about this, please say which of the following statements comes closest to your own view, even if none of them exactly describes what you think?’

…only 26% answered…

“Climate change is happening & is now established as largely man made.”

While 25% answered…

“Climate change is not happening.”

When asked about the consequences of climate change…

‘Would you say that, in general, the risks of climate change and its possible consequences have been presented proportionately, or do you think they have been understated, or do you think they have been exaggerated?’

…36% thought it had been exaggerated.

That’s massive scepticism in the UK equating to…

• One quarter of the population thinking there is no global warming taking place
  
• One third thinking that the risks have been exaggerated

What’s exaggerated by the two photos above? Does anyone know why glaciers retreat like this?

Rising Temperature, Rising Temperature, Rising Temperature!

Less snow fall and a lubricating layer of water between the base rock and the ice, equals less ice formation and greater ice loss at the face respectively.

Southern Hemisphere                                                                                .

Down in the southern hemisphere melting ice is also a concern as reported in the NewScientist in January 2010.

The Pine Island glacier in western Antarctica may be past it’s tipping point when a massive collapse becomes inevitable.

It was first reported to be thinning in 2004, but the recently completed survey of the ice shelf in 3D showed that it had irreversibly passed the tipping point, where it will lose 50% of it’s ice in the next 100 years.

The consequences for global ocean levels is a rise 24 centimetres (0.8 feet).

The reason for the collapse is warming seawater which washes up beneath the ice shelf pushing the grounding line (the point where a floating ice shelf becomes a grounded ice sheet), further up the continental shelf.

The situation is exacerbated by the shape of the sea bed which rises to a lip, then drops again into a bowl before rising again proper to the shoreline. The survey found that once the ice has retreated beyond the lip, a rapid and irreversible loss of ice occurs.

The USGS and the UK Hadley center both predict a sea level rise, due to oceanic thermal expansion alone, of 1 to 2 metres (3 to 6.5 feet) by 2100, based on a global temperature rise of 2 degrees Celsius (3.6 degrees Fahrenheit).

Imagine what effect this will have on an already under threat Antarctic ice shelf!

We Don’t Need Science To Confirm What We See                             .

These are observations of what is actually happening right now, forget whether the science is dodgy or not, this is actual physical evidence. Forget whether it’s man made or not, no one else has the capacity to slow down or halt global warming but us.

If you don’t think it’s important just think on this.

We are at the beginning of the effect right now. You think global warming is a natural phenomenon? You’re right! It keeps the Earth inhabitable, right again!

Have you ever heard of runaway global warming? I have and it occurred in the Cretaceous period when the polar ice caps melted and disappeared entirely.

There were lush sub-tropical forests at northern Alaskan latitudes!

The climate is a complex integration of feedback systems, some positive, some negative.

Take the albedo effect, which is a measure of the reflectivity of a surface. Fresh snow and ice reflects some 30% to 80+% of the suns energy right back out to space. Whereas seawater has a low albedo effect, only reflecting ~4%, and dark soil up to 15% of the suns energy.

When the climate is in balance the polar ice caps help regulate global temperature by reflecting just the right amount of the suns energy back to space. If however the global temperature experiences a rapid warming, then polar ice begins to shrink thus reflecting less energy back to space.

Less reflectivity equals more of the suns energy becomes absorbed in the troposphere, equals a higher global temperature. As more and more ice is lost warming becomes exaggerated in what’s known as a positive feedback loop.

So if you are a climate sceptic I ask you not to get bogged down in the ‘who is responsible’ but to look at such observations as shown here, then to ask yourself, ‘how do we stop this from happening’.

If you want to help prevent global warming becoming more of a news headline in the future, you can download my ‘100 Green Living Tips’ pdf to the right, to reduce your impact on the climate by curtailing your carbon footprint.

Sincerely,

P.S. Click the link to see the full climate sceptic poll from the BBC.

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1. Himalayan Glaciers ARE Melting

While the Intergovernmental Panel on Climate Change (IPCC) attempts to rescue it’s reputation, after issuing it’s flawed report, the fact remains-

Himalayan Glaciers ARE Melting!

Himalayan Glacier Melt

The IPCC’s report from 2007 contained claims that mountain glaciers are melting on all the world’s continents, and the cause was global warming.

However, these claims were based on two unsubstantiated articles. Firstly, a dissertation by a geography student who based his conclusions on conversations with alpine guides, and secondly, a report found in a popular climbing magazine which again was based on observations made by mountaineers.

Although glacier retreat is being observed in all mountain regions, the mountaineers were hardly qualified climate scientists. Herein lies the problem.

The IPCC is supposed to provide authoritive scientific evidence, it was therefore incumbent upon them to establish peer review, and to be secure in their claims before presenting them to a nervous world.

Inevitably, global warming sceptics have seized on the mistake to call the IPCC discredited and so should be disbanded.

I think the real damage may well be with the millions of ordinary people around the world, whom are yet to be convinced that global warming and therefore climate change, is indeed a threat. What kind of message does the IPCC send to them?

The fact remains that glaciers around the world ARE in retreat. That’s not a regional aberration, but a global phenomenon.

So what is the explanation if not global warming?

What Is Global Warming

Global warming is the warming of the Earth due to the greenhouse effect.

During daylight hours, incoming solar radiation enters the atmosphere to warm up the troposphere and Earth’s surface. During the nighttime, the absorbed long wave thermal energy is radiated out into the atmosphere where it is eventually dissipated into the stratosphere and beyond to space.

Simply put, it is the balance of incoming energy against the outgoing energy that determines whether the overall energy budget for the Earth is in the black, or in the red.

When they are equal the Earth’s temperature remains stable. However, when less energy is lost to space than is absorbed, we have global warming.

It is a group of gasses in the atmosphere known as greenhouse gasses, around which, the controversy revolves.

Their quantities are so small yet without them the Earth would be too cold to be habitable. They are chiefly…

• Water Vapour
• Ozone
• Carbon Dioxide
• Methane
• Nitrous Oxide

These gasses naturally absorb energy in the infrared wavelength during the day, then re-radiate it back to Earth. Simultaneously they absorb the outgoing thermal energy radiated into the atmosphere from the ground during the night, increasing the trapped energy.

Too great a quantity of greenhouse gasses in the atmosphere, means too much thermal energy is trapped in the troposphere causing heating.

Global Temperature Trend

As the graph shows, the trend has been up +0.8 degress Centigrade between 1860 and 2000.

Global warming IS occurring as evidenced by the retreat of the Rombuk glacier since 1921, and the temperature record since 1860. Is the cause sunspots, anthropogenic greenhouse gas production, or is it a natural deviation?

What I do know is, that since the onset of the industrial revolution around 1800, the quantity of greenhouse gasses pumped into the atmosphere by man must be trillions of tons! The rising global temperature coincides with the industrialization process! Also there is no other viable culprit based on today’s evidence!

It’s like the murderer who gets off, yet the police say they are not looking for anyone else in connection with the crime. It’s obvious what has caused the current global warming trend, all we have to do now is to proove beyond reasonable doubt that we did it.

So the Himalayan glaciers won’t have disappeared by 2035, but they could well do by 2135 so that’s alright then? The IPCC got it wrong, but we can’t ignore what our eyes tell us.

So let us stop concentrating on who did it, the time has arrived to focus on how we prevent it. Don’t let us be the modern day Nero!

Sincerely,

P.S. Please sign up for my RSS feed or newsletter for more news and information.

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The UK’s green energy commitments have fallen way behind it’s European counterparts in the past years, despite numerous oral and policy wordings. This time there is no leeway for delay!

The Energy White Paper 2007 set renewable electricity targets of 10% by 2010, and 20% by 2020. Also renewable energy overall to be 20% of total by 2020.
The Climate Change Act 2008 bound the UK to reduce CO₂ emissions below 1990 levels, a minimum 34% by 2020, and 80% by 2050.
The Low Carbon Transition Plan 2009 also commits the UK to obtaining 15% of electricity from renewables by 2020, in-line with the EC’s Energy Directive 2009.

However, even now the UK’s progress is stuck in regional planning consultations.

So when we hear that Gordon Brown the British Prime Minister is to announce this week, a £100 billion offshore wind development, including some 3500 turbines, we know that it will become bogged down in planning consultations for the foreseeable future.
Lets hope that the Dogger Bank area of the North Sea has no NIMBYs (not-in-my-back-yard), as a number of turbines with 10 gigawatt capacity are planned here.

In addition this week, the German newspaper Suddeutsche Zeitung reported that, nine European countries plan to develop a high voltage power grid under the North Sea. This with the intention to distribute their renewable power generation, which is expected to iron out the weather related fluctuations, a major draw-back of green energy.

The 10-year project includes connecting wind farms off the coasts of Germany and the UK, tidal barrages off the coasts of Belgium and Denmark, hydro-electric schemes in Norway, and wind and solar schemes on the European mainland.

The newspaper reports that there are existing offshore wind farm contracts to provide 100 gigawatts of capacity, equivalent to approximately 10% of Europe’s total energy needs.

So now we have it. The UK has 10-years to get it’s renewable energy systems up and running, or they will have no green energy to share with the rest of northern Europe.;)

Sincerely,

P.S. I would love to have your comments on this post, so go ahead and let me know what you think!

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3. Tidal Power A False Hope?

Apart from the obvious target of cutting CO2 emissions to a level that will prevent the worst effects of climate change, what are the definitive achievements set by the Copenhagen summit?

I’ve been able to dig out some specific targets to enlighten you with…

1. Cut CO2 emissions in the developed world by 25-40% by 2020, relative to 1990 levels.
2. Curb and prevent CO2 emissions in the developing world from reaching significant levels.
3. Get developed world countries to pay for low-carbon technology and to pass it on at low cost to developing countries.
4. Developing countries want funding, to reduce emissions and to develop and disseminate clean technology, distributed by the UN.
5. To curb the speed of deforestation because 17% of emissions comes from razing forests to the ground.
6. Clean technology products and services must be distributed around the world rapidly, but is a regulatory body necessary to oversee this or just an advisory one?

…but will agreement be reached?

Developing countries still insist that they are not responsible for past greenhouse gas emissions, and that developed countries whom are responsible, should pay for the cleanup. Furthermore, they don’t want their progress of development to be curtailed.

Developed countries insist that all countries must take their part in combating global warming and climate change, as it affects all countries.

Just to put you in the picture here is a chart showing, country by country, the quantity of CO2 emissions since Kyoto – 12 years ago – and the percentage increases or decreases…

Carbon Emissions Graphic

… which shows interestingly, that the U.S. has been the worst polluter in the past 12 years. What it does not show however, is that China took over as the world’s greatest carbon emitter in 2006-2007.

What I would like to know, is whether our world leaders can make this a historic summit, or will they reduce it to a lot of wind and air. Even if an agreement is reached, will they act on it with speed and due diligence?

Based on past success, and the unwillingness of our political leaders to act, I can’t say I’m too hopeful. I only hope they realize, that they act on all our behalf’s and not just their vested interests!

P.S. You can read more and download the chart in pdf here.

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3. China Takes The Lead

CO₂ Emissions

China makes a new policy statement, November 25, ahead of the Copenhagen climate summit.

China will cut the intensity of carbon dioxide emissions per unit of gross domestic product in 2020 by 40 to 45 per cent from 2005 levels, said a statement from the State Council, or cabinet.
This is a voluntary action taken by the Chinese government based on its own national conditions and is a major contribution to the global effort in tackling climate change,” the statement said. ~Source

This is the first time China has linked CO₂ emissions reductions to a percentage of it’s economic growth.

This following President Obama’s announcement that he will attend the Copenhagen summit to offer a cut in US emissions by 17 per cent from 2005 levels by 2020.

So the world’s two most polluting nations have made substantive promises to reduce carbon dioxide emissions. Lets hope India and other large polluters follow the lead.

Renewable Energy

From water heating to power plants, China is the largest market and producer of solar equipment. In 2007 it is estimated that 30 million homes used solar water heating SWH cutting carbon emissions considerably.

WUXI, China — President Obama wants to make the United States “the world’s leading exporter of renewable energy,” but in his seven months in office, it is China that has stepped on the gas in an effort to become the dominant player in green energy — especially in solar power, and even in the United States. ~Source

…this is because low cost Chinese labour is helping to push down world prices for solar panels.

Chinese government officials signed an agreement on Tuesday with First Solar, an American solar developer based in Tempe, Ariz., for a 2,000-megawatt photovoltaic farm to be built in the Mongolian desert.
Set for completion in 2019, the project represents the world’s biggest photovoltaic power plant project to date, and is part of an 11,950-megawatt renewable energy park planned for Ordos City in Inner Mongolia.
The agreement calls for ground to be broken on the first 30-megawatt phase of the project by June 1, 2010, followed by 100-megawatt and 870-megawatt additions to be completed by the end of 2014. A final 1,000-megawatt phase is scheduled to go online by Dec. 31, 2019. ~Source

…with the capacity to power 3 million homes when completed. First Solar are still the world’s largest manufacturer of photovoltaic modules.

The country has doubled its capacity for wind-generated power every year for the past four years, and President Hu Jintao pledged last week to turn to more sources of renewable energy in coming years. ~Source

…to ensure the commitment.Theoretically China could cut 30% of it’s carbon emissions by 2030 through wind power alone, but it would take a huge investment over the 20 years.

Food For Thought

Is it feasable to have more than 10% of a nations electricity supplied from a renewable source that is as unpredictable as wind?

With huge investments being made into solar electricity generation, how much power can a northern hemisphere country expect to generate from solar?

Please leave your comments below, I would be very interested to hear your views.

Sincerely,

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