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The Heavyweight Sea Snail
Roland Piquepaille writes "Scotland, like many European countries, must comply with regulations requiring that a mandatory percentage of the energy it uses comes from renewable sources. For Scotland, this percentage will be 18% in 2010 and 40% by 2020. One of the programs in development is Ian Bryden's sea 'Snail' program. The Snail is a 30-ton anchoring device which uses hydrofoils -- wings that 'fly' in the water -- to generate enough power from tidal waves to service 10,000 homes by 2007. This overview contains more details and a picture of a prototype of the Snail with its six wings." There are several mentions of this in UK newspapers and the Scottish government webpages.
Let's hope it does better than the Salter's Duck. The development project was cancelled in the 1980's after UK government departments grossly over-estimated (by a factor of 10) the cost of the electricity it was going to produce. Cock-up or conspiracy?
I never tried escargot, and probably never will, but I saw snail, 30 ton and almost lost my lunch.
It seems that a fair amount of research into new power plants is coming to fruition - the latest New Scientist had an essay on the JET (Joint European Torus) breaking even on its power budget for nuclear fusion. The big argument now is not whether to build one that ought to provide 10x its input requirements, but where to build it (France or Japan, from memory).
With windfarms (popping up all over Scotland and the exposed areas of England - presumably Ireland as well, that's one hell of a windy place
Simon
Physicists get Hadrons!
This is all part of an alien conspiracy to bring the moon crashing down on us! Awaken to the truth before it's too late!
Doesn't this just steal energy from the moon? Leading to disastrous complications if our insatiable moon power lust is not quelled.
The article mentions that the device is able to "generate more than 200 tons of downward force to the seabed", but nowhere does it state how that force is used. A static force does no work and therefore can generate no energy.
5MW is good for 10,000 homes, so a house in Scotland only uses 500 watts of electricity?
Who's to say that's not desirable - for the state. One's power increases with each person dependant on you, all the better to guarantee your position in government.
At the bottom of the endless pile of paper work which characterizes all regulation lies a gun.
Alan Greenspan
Better than being caught in 20 years time with rising oil prices and a renewable energy industry that went bust 15 years ago, isnt it?
Things like this are amazing ideas and very, very, very important and will only be increasing more so. Oil won't last forever. You know it. i know it. Why beat around the bush (no pun) and say 10, 20, 50, etc years? Who gives a fuck *how* long we have....get on the ball and get renewable energy sources up past 95% of out uses.
Sad part is tanks and planes don't run on well wishes and rainbows, the US military and the non-efficient consumer vehicles have *got* to be brought under control. Go ahead and argue all you want. You are wrong and we have *got* to get off of energy sources that will run out.
Also, i'm happy this sort of thing is being done....just wish more and more stories of new energy studies (that don't involve how to make *more* money for oil companies) come from the US. We either need to get *everyone* behind this or it's not going to happen. People, in general, are lazy and won't change unless they have a personal interest or are forced to. Let's get some grants and scholarships for people doing this kind of work in the US.
Sorry for rambling and not spell checking.
According to this site:
"Currently, although the technology required to harness tidal energy is well established, tidal power is expensive, and there is only one major tidal generating station in operation. This is a 240 megawatt (1 megawatt = 1 MW = 1 million watts) at the mouth of the La Rance river estuary on the northern coast of France (a large coal or nuclear power plant generates about 1,000 MW of electricity). The La Rance generating station has been in operation since 1966 and has been a very reliable source of electricity for France. La Rance was supposed to be one of many tidal power plants in France, until their nuclear program was greatly expanded in the late 1960's. Elsewhere there is a 20 MW experimental facility at Annapolis Royal in Nova Scotia, and a 0.4 MW tidal power plant near Murmansk in Russia. "
I also recall having seen articles talking about attempts in Norway to capture wave/tidal energy for electricity generation.
I'm always a fan of renewable energy. I just wanted to point out that this is more an attempt to do something in a new way than to do something new.
Things to do today: See list of things to do yesterday
It's not socialism, it's simply a mandate to cover everyone's asses. As non-renewable sources are depleted (or grow more expensive), it will be better to have an extra decade or so of development - not to be desperately scrambling for a solution.
I don't know much about the initiative in question, so please don't read this as an unqualified endorsement. However, one factor that needs to be borne in mind when looking at the "affordability" of an alternate power source is its sustainability.
Energy from petrochemicals is not sustainable. It might be cheap - right now - but it's not going to last. Moving to sustainability while we have cheap petrochemicals to help us get there makes sense. I think it's high time that environmental costs, lack of sustainibility, and other "externalities" were factored in when comparing "affordability". Cheers!
Corruptissima re publica plurimae leges.
How was the parent post modded Score:0,Troll ?
It is a good point that if there were regulations like that in the US, things might be very different. I think few would argue that we depend on oil for to many of our energy needs.
The annoying part which neither the summary or the article address, is that a country is sovereign and is not *required* to follow regulations setup by another group. It may choose to take part in a treaty, or follow similar guidelines as other countries, but *required* is another story. But alas, there is no supporting information on said regulations and/or their origin, so we must blindly accept everything that is said!
But I digress....
It seems we could quite happily reach our targets. Our 3rd largest city, Aberdeen, will be powered solely by wind in the near future (as a large wind-farm out at sea is in the pipeline. Quite ironic, as Aberdeen is the oil capital of europe :). IIRC The Isle of Skye may also have a windfarm and there's a couple more planned.
Forget about solar energy though, our annual sun quota (approximately one day, give or take a few hours) would provide enough energy to power a digital watch. For a few minutes. Just.
While they don't say so in the article, it would appear from the picture of the device that there is a medium diameter horizontal axis generator on the dorsal surface, and the six foils are going to generate the downforce required to anchor the device to the bottom.
This is just from looking at it, obviously not from the plans. One of the challenges they would face with any form of tidal or current energy device is how to keep the thing in place. With the foils, I can see issues with keeping it in position, but it does seem like that's what they're trying to do.
There's probably also a hard mooring to keep it from drifitng away at slack tide, which would also allow it to change facing when the tides change direction or the currant shitfs.
Never attribute to malice what can as easily be the result of incompetence...
This link explans better how the sea snail works. http://www.friendsofscotland.gov.uk/education/rene wable.html
Basically, the foils are to keep the snail anchored while the turbine is moved by the water.
quis custodiet ipsos custodes
This is all part of an alien conspiracy to bring the moon crashing down on us! Awaken to the truth before it's too late!
Actually, tidal friction slows the rotation of the earth and raises the orbit of the moon. Extracting tidal power will increase the friction and thus the rate at which this happens.
(Of course if there WAS a chance of bringing down the moon that would make for QUITE the "environmental impact".)
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
In this case it's not oil that we are dependent on but COAL. Now while we mine coal right here in the US remember that coal mining is by far the most dangerous occupation in the US, for each coal plant in the US one coal-miner is killed each year in an accident. This doesn't count the long term healt and psychological effects that mining has on a person. Nor does it take into effects the polution generated by a coal plant. Sorry, but oil fuels some of our energy needs (heating and automobiles) but very little oil is used in electrical power generation.
The City of Austin (Texas) owns its own power company and has mandated that it will generate 10% of its power from renewable sources over the next 10 or 20 years. It will be interesting to see how successful they are.
The state has had a huge role in creating new technologies. Half the stuff in the computer industry, a great deal of basic research in genetics, in physics. People seriously overestimate the contributions that the free market to science and knowledge as a whole.
Private corporations are great at going the last mile, making a processor or a hard drive that's 10% better than last year.
They're less good at pumping in huge amounts of money to make a technology initially feasable or doing basic research.
The free market provides substandard information. There've been several studies of rogaine published in scientific journals. Those funded by industry (even though industry doesn't disclose their funding, sometimes in violation of the pubishing journal's standards ) often show a drug doing much better than government funded research shows it to be.
Besides, many countries try to lure venture capital, which creates jobs. Better infrastructure and more stable energy costs are considerations for major manufacturing concerns which help more developed countries compete with cheap labor.
Besides, if you have high unemployment projects like this can create jobs as well as contributing to the economy. And unemployment creates more problems than just people not working (crime, drug use, etc.)
___
It's the end of my comment as I know it and I feel fine.
I parked a number of times at the (old) Austin airport, and noticed that the acres upon acres of asphalt would have been a great place to hang solar panels over. "Shingling" carports with some sort of solar collector would have had the dual benefit of generating energy and keeping the vehicles below from cooking in the sun (one wonders how much those cars contributed to smog from evaporative fuel emissions; you can't purge a vapor-recovery canister when the car isn't operating).
Time is Nature's way of keeping everything from happening at once... the bitch.
I don't know why we bother putting our money into these centralised energy projects. Why not just mandate that all houses must have photovoltaics and solar heating installed? We just had solar heating installed, which works great even in sunny Britain. Photovoltaics would be more expensive (20K UKP expensive) but we calculate that they could provide about 120% of our idle energy needs, so at night the grid would actually have to pay us! :) The payback period would be ~ 6 years we estimate.
Just a little more thought, and the government could easily reach their European targets at little cost to themselves, and with no new R&D.
While it is true that coal mining is still a rather dangerous occupation, the polution generated by coal-fired power stations isn't as bad as many people belive. In the last few decades, coal has come quite a long way in reducing toxic emmisions. Modern coal plants combust the fuel much more completly, and are outfitted with high-tech (and very expensive) scrubbers to remove the really toxic byproducts (especially sulfer).
Considering that our coal supplies will long outlast our oil supplies, I think that its still a good idea to invest in cleaner coal technologies. Linky.
This seems an interesting project, though another project in Scotland, the Pelamis seems more interesting and closer to completion. A an old Uni mate of mine works at Ocean Power Delivery which has spent the last few years developing the Pelamis, which is basically a 120m long 3m round articulated snake. A working full-scale prototype is currently getting installed in a channel around the Shetland isles. The software and control systems seem really interesting due to the large amount of backup systems and the use of FPGAs.
Uh, that's a great business model, and one that's alive and well in the neoconservative politics currently controlling our country.
But the impending bankrupcy of oil supplies is NOT a fairytale. I think it's obvious, or at least it should be, that getting power by burning or exploding several millions of barrels per day of a substance that exists only sparsely is not the sort of thing we can do forever. My relatively ecomoderate history professor liked to quote that oil supplies will start to run out around 2040, using 1992's numbers. And our consumption has increased vastly since then...not due to the SUV as some will tell you, but due to increased petroleum usage in the industrial development of second and third wave nations, as well as increased reliance by first wave nations.
Personally, I'm not too worried, because right around the time that oil gets really scarce, all of the hundreds of alternative solutions that are already fairly mature will suddenly become viable. At that point, whoever has the best, most efficient way to use the elements to make juice will stand pretty strong against the backdrop of nations scrambling to gather their their oil money.
Europe has these regulations to decrease the potential effects of oil greed. When the oil crunch comes, they're half way to neutrality. If the US had regulations and incentives, or rather, more of them (NY does offer tax credits for alternative fuel sources but they're break-even deals, not something to bank on), we wouldn't have to worry either. "Let the Arabs fight over their oil, we've got solar farms!" Unfortunately, America's caught between myopic politicians and a still strong petroleum industry trying to squeeze as much as possible out of their remaining power. The end result is -- well, war, high fuel prices and an intense media driven hatred of "green" politics.
Hey freaks: now you're ju
We already have a lot of fuel-saving technologies which will pay for themselves nicely at current prices (let alone future prices), yet adoption has been very slow. I can think of a number of causes:
- Tax subsidies which have the effect of paying users not to change.
- Outmoded regulations which slow or even block desirable change.
- Interest groups which resist changes which threaten their way of doing business.
- Simple inertia.
As an example of 3 and 4, I hold up the continued widespread use of stick-built construction when SIPs (Structural Insulated Panels) leak a lot less heat, have next to zero air leakage when properly installed, and save a lot of time and labor in the construction. They also reduce the use of wood. We should be promoting or mandating their use where feasible and training builders and building inspectors in their proper installatino. Are we? No. I'll bet there are a lot of union carpenters who like it that way.Another is the relative lack of CHP (Combined Heat and Power, or cogeneration) systems in the USA vs. Europe. This may be due to power regulations which make it impossible to obtain a market price for the production of small generators, or far too expensive to connect to the grid save as a pure consumer. Again, this is something which can be fixed with proper regulatory changes.
There are questions not answered in the article about the snail, such as the handling of the variable output of the tidal power systems versus the contrary schedule of grid demand. These things must be dealt with; unfortunately, they are beyond the scope of small news items. What's truly a pity is that news editors don't think they are sufficiently important to collect links for further study.
Time is Nature's way of keeping everything from happening at once... the bitch.
Not to nitpick, but coal mining is the number 2 most dangerous occupation in the world IIRC. Commercial fishing is substantially more dangerous.
Bonus points for tilting the turbine so as to generate a lift moment downward and use it to produce some of its own downforce.
Time is Nature's way of keeping everything from happening at once... the bitch.
The fact is that private companies do not have the long-term interests of society in mind. They have a mandate to increase profits.
Socialism is bad when it causes the state to interfere in short-term market issues (ie, price fixing), because no single entity can affectively micromange such a complex system. But applying broad long-term pressures to the market is not socialism, its a smart policy that recognizes the deep complexity of the market system.
These seemed like valid concerns at first glance, but the numbers just don't add up. It's something we often deal with in physics; it's very hard for humans to compare quantities which are very very large.
The amount of energy we're extracting from the water is miniscule. Take the 5MW sea power station. Water weighs 1 gram / cc, which means 1000kg per m^3. 5 MW in 1 second is the kinetic energy (using E=(1/2)m(v^2)) in 100 cubic meters of water moving at 10 m/s: E=(1/2)(1000gm)(100m/s)^2 = 5e6 joules. 100 cubic meters, even once a second, is NOTHING compared to the rest of the sea. 7/10 of the Earth's surface is covered by water; the seas have an estimated volume of 1.4*(10^18) cubic meters!
Huge solar plants will abosorb their energy from our sun. That energy would have heated our soil, been absorbed by plants, been reflected back into the atmosphere...
The amount of land affected is exactly that in the shadow of the solar array. No more, no less. Even the power we "extract" from that shadow returns to the environment in the form of heat, after it's used in the grid. Remember, energy is always conserved.
Geothermal generation will cool our planets core faster
This one really set me off. Come on people, the Earth is a GIANT BALL OF MOLTEN ROCK. The crust, with all the seas, life, solid rocks and mountain chains, is a few miles on top of it. The radius of the Earth is 4000 miles = 6400km. It has a volume of 1.1*(10^12 cubic KILOMETERS)! You could literally pour every ocean on Earth (10^9 km^3) into the mantle, boil it off into space, and barely make a dent in the temperature. There's a reason it takes billions of years for planets to cool.
Think about replacing a nuclear power plant with a tidal generator. You are sucking an entire nuclear power stations energy output from the ocean! Don't you think that might have some sort of consequences? And that's just one nuclear power plant. There are dozens!
This seems really logical, because to humans a nuclear power plant generates an enormous amount of energy, i.e. many orders of magnitude more than it takes to run your electric razor. But the power in the oceans (7/10 of the Earth covered by VERY dense material moving about) makes those power plants look like coin cells by comparison.
The only solution is to be more efficient, not to try and generate more power.
On this point I agree with you in spirit, but have to point out that it will simply never work. Google for "The Tragedy of the Commons" if you want to know why. Simply put, any person/organization which tries to consume less energy puts himself at a competitive disadvantage. It sucks, but it's the way economics work.