It's a nice idea but costly compared to solar even in places like Scotland.
To remind, the MeyGen project’s Phase 1A involved the installation of the AR1500 onto a gravity-based foundation, alongside three other AH1000 MK1 turbines, to form an array of 6MW.
From what I've found, the AR1500 has just had routine quarter-life maintenance[2], but I can't find anything concrete right now which of the four made the 6 year milestone. I do note that in the brochure[3] for the AR1500 they claim three service intervals every 6 1/4 years, rather than four service intervals as indicated by the article.
[1]: https://www.offshore-energy.biz/simec-atlantis-troubleshooti...
[2]: https://www.offshore-energy.biz/overhauled-meygen-turbines-t...
[3]: https://simecatlantis.com/wp-content/uploads/2016/08/AR1500-...
If 1/4 make it then you at least know it can be done and hopefully learned a couple key failure modes from it
From that link:
"The first of these turbines is scheduled for redeployment in May 2022, with the final turbine to be deployed in March 2023, complete with a retrofitted wet mate connection system, which more than halves the costs of future turbine recoveries and deployments."
"The company’s AR150 turbine was re-deployed last month, after being out of the water for upgrade and maintenance work."
The single long-running turbine can be compared to the upgraded turbines to measure the effect of the upgrades, and it provides the headlines this thread is about. The upgrades themselves are also clearly valuable R&D work.
> complete with a retrofitted wet mate connection system, which more than halves the costs of future turbine recoveries and deployments."
Why do they need recoveries if not for maintenance? Why did they need to cut the cost of maintenance if no costly maintenance were needed?
> after being out of the water for upgrade and maintenance work."
How is this not literally validating GPs comment?
Anyone can say "the new ones won't need maintenance and the only reason we took them out was to improve them", but they could've worked on better ones and deployed them without removing existing ones. Removing existing ones mean they broke. So until the new ones last as long, GPs analysis is the correct one.
Upgrades. Was already answered.
> Why did they need to cut the cost of maintenance if no costly maintenance were needed?
To improve the ROI. If maintenance is needed, it will be cheaper going forward. How often the average turbine will require maintenance is harder to determine based on the information available. We know it might be somewhere between a few years and ~6 years.
> How is this not literally validating GPs comment?
It does not say anything about maintenance being required or costly.
> Anyone can say "the new ones won't need maintenance and the only reason we took them out was to improve them", but they could've worked on better ones and deployed them without removing existing ones.
That requires more investment (the things ain't cheap), and it does not show whether successful maintenance is possible or how expensive/cumbersome that maintenance would be, which are very important pieces of information for determining ROI.
We don't know, but there are other reasons besides maintenance and it is a huge unfounded assumption to say that is the only reason. Upgrading an existing installation for better performance is likely orders of magnatude less expensive than building additional units, building the archor points, and emplacing them, so it could have been getting more data out of less budget.
They may not have permits/authorization for additional locations yet.
The upgrades may provide a significant ROI improvement and the only reason they didn't upgrade all of them was to leave one to look at long term reliability while sacrificing the improved ROI.
But fundamentally, we just don't know. While required maintenance is one possibility, it is by no means the only one.
If you made 4 loaded dice and continuously rolled them for 6 years and 1 of them consistently rolled a 6 everytime then yes, it is entirely possible.
I'm hoping for a good renewable energy source as well but that doesn't mean I have to accept shoddy statistics.
1.5 MW is nothing to scoff at, so if it costs a bit in maintenance that's okay. But overall costs would be great to know.
Sure, there are many parameters to consider, but it's the kind of thing energy analysts do all the time.
The article likely double-dips on this by saying that 6MW could provide for 7k homes, which it obviously can’t at peak use.
Also I would say the expression "powering a home" usually implies average demand not peak demand.
Assuming these turbines are always at nameplate production, which they are not, they produce 6MW. Spread among 7k homes, that’s less than 1kW, which is not a lot.
Given the previously stated peak of 2.6kW per household, 6MW would cover about 2300 homes.
The only way you could get to this kind of number would be if you calculate the average use for a household over a year. But then you would have to compare it to the plant’s yearly production rather than its nameplate capacity.
Wikipedia quotes MeyGen at 10.2GWh in 2023, that means 1.14MW on average instead of 6MW. Assuming perfect storage, that would mean an average of 163W per house for 7000 houses. That is barely enough for a fridge.
> Also I would say the expression "powering a home" usually implies average demand not peak demand.
That's my issue. Comparing average demand to nameplate capacity is dishonest.
An efficient European fridge uses less than 250 kWh/a, or less than about 30W on average.
E.g. this uses 127 kWh/a: https://www.bosch-home.com/de/de/product/kuehlen-gefrieren/k...
[1] https://www.ofgem.gov.uk/information-consumers/energy-advice...
[2]: https://assets.publishing.service.gov.uk/media/67e3eae39c9de... - see background section
In many countries, 1kW is more than enough to cover electricity usage in a household. https://ec.europa.eu/eurostat/statistics-explained/index.php... says “Electricity consumption per capita in the household sector in the EU in 2022 was 1.6 MWh per capita (1 584 kWh)”.
That’s about 4.3kWh/day or 180W. https://ec.europa.eu/eurostat/statistics-explained/index.php... says there were 202 million households in the EU in 2024, on a population of about 450 million, or 450/202 ≈ 2.2 persons/household.
So, on average, a household in the EU uses less than 500W of electricity.
If you want to compare power use of a household averaged on a year to yearly production of these turbines:
- 1.6MWh * 2.2 people per house = 3.5MWh/household
- 10GWh produced in 2023 / 3.5MWh = ~2860 households supported.
> The actual statement is "producing" 1.5MW.
I have no doubt that the author could write that. My message points out that it simply is not true.
[1]: https://simecatlantis.com/wp-content/uploads/2016/08/AR1500-...
For instance, there's the https://www.esig.energy/wiki-main-page/general-electric-1-5-..., which has ~40m blades. The AR1500 (which is what these tidal generators are using) is smaller, with "only" 9m blades.
So it's significant in that these aren't toy devices, they fit in a very similar place in the engineering ecosystem as conventional wind. They should be a real competitor.
GE's 1.5MW models are 20 years old.
Private, entirely for profit companies, have recently answered large government tenders in the middle east to sell power at the equivalent of $0.05 USD per kWh. They are fairly confident that they can make a profit doing this, even with the cost to incur the long term debt to privately build a massive solar power plant.
The cumulative amount of solar power being produced within Germany right now is a good example of its practical use in a less sunny climate.
In terms of placing things in the ocean, hiring the sort of offshore work vessel with a built-in crane can go and place or remove multi ton apparatus is very costly. Maritime construction for things like laying coastal submarine cable, building piers and docks and marinas, setting and maintaining marker buoys isn't cheap.
Laying and maintaining HV AC or DC submarine cables in salt water is also particularly known to be expensive. Hiring a 36'-42' aluminum landing craft for coastal construction projects, with fuel and crew can be easily $500 an hour.
Labor and vehicle costs are greatly increased compared to doing things on dry land.
Having different types of power generation provides redundancy. The wind still blows at night, the tide still comes in and out when its cloudy, etc. Grid storage is nowhere near a solved problem, so something like tidal could prove less expensive than storage or overbuilding alternatives to overcome their variability problems. Even if it doesn’t end up being widely useful, it could still end up finding a use in more niche applications.
Finally, it can and will improve. 30 years ago, solar was not price competitive and decades of development and iterative improvements have changed that. We should keep developing alternatives to see their full potential.
Doesn't even need to be less-useful land (especially in western Europe, ground is becoming a scarce resource), put PV on flat rooves or add them over open car parks. Also helps alleviate pressure on the overstressed energy grid by generating and using power more locally.
But, local power is (overall) a lot more costly than major centralized power generation projects, like a wind farm or what have you.
Eg: https://www.next-kraftwerke.be/knowledge-hub/balancing-marke...
Not sure if this is prominent in the Irish market or not
all systems require maintenance, so "costly" is relative; would need more specifics to determine whether this is a cost effective solution or not
How do the maintenance costs (and intervals) of these compare to gas/steam turbines?
The resins used for carbon fibers are usually very bad at contact with water over long periods of time. Even those in aerospace applications require coating/paint if exposed moisture over time. It’s a plastic, even the best ones don’t do so well in water after a few months.
Furthermore, the damage that moisture does to the resin can be difficult to detect and even more difficult if not impossible to fix. It requires clean rooms, skilled labor and machinery that you don’t have in the middle of an ocean.
Then take iron corrosion: it is easy to spot by naked eye, it may not be easy to repair, but it is relatively simple to “halt” further damage by removing the rust and adding new paint.
Don’t get me wrong: carbon fibers are amazing, but sometimes the “boring” solution is best.
PS: steel alloys and coatings can be amazingly high tech too, it’s amazing what can be engineered.
https://www.popularmechanics.com/science/a60687211/titan-sub...
Also, I am thinking about all the ocean factors beyond salt corrosion. There's tons of crap in the water beyond salt and minerals. Like fine grit suspended in it. Plus the tidal forces etc.
While rust can be a problem it can be mitigated. Also steel is easier to repair than many other materials (welding).
BTW. Aluminium does suffer from corrosion as well. I used to have racing bike, the wheel nipples (these connect the spokes to the wheel rim) used to corrode to the point where they would fail, which meant I would end up with a buckle. I ended up having both wheel rebuilt with higher quality brass nipples.
Plastics under time also suffers from a different set of issues. Plastics can become brittle. Anyone working on old computers (especially macs) can attest to this.
As opposed to other forms of energy production which have free/zero maintenance?
* this is a record for the time a turbine has been under the sea without any maintenance, which proves its commercial viability
* because it generates powers during high/low tide, and because the lunar cycle is different to the solar cycle, it could help fill in the parts where solar falls off in a predictable way
BUT:
* Tidal energy is valuable but geographically constrained
* Only a few countries have suitable locations for it (UK, Canada, France, South Korea)
* The Global Technical Potential (in TWh/year) is 1/10th of offshore wind
I assume the value is still massive? The UK is still aiming to 4x its Off Shore wind by 2030. That would be 60% of UK electricity. If the new Nuclear Power plant actually deliver double its current 15%, that would be total 90%. The rest could just be solar and underwater turbine.
I am just wondering if underwater turbine causes any issues with marine life. If not we could absolutely deploy them on massive scale and avoid the eye sore of Wind Turbine.
The Annapolis Royal Tidal Station shut down 5 years ago, because it had a strong tendency to chop up all and any fish that went through the intake.
It's unlikely that Nova Scotia will see tidal power again in the near future. There's been some attempts at in-stream generation, but the projects have been opposed by the local fisheries, and the federal regulators don't seem interested in helping define the requirements.
At high and low tide the water isn’t moving much. Surely it generates most at mid tide, with the flow reversing direction causing a lull?
This makes the useful portion of the cycle far far larger.
Yes, of course. I do not get the point, this is not a solution to every electricity generation problem
> * Only a few countries have suitable locations for it (UK, Canada, France, South Korea)
There are more than that. I have a seven knot tidle current 5km from my house, not mentioned in your list. I know of others. The costal conditions are quite common for this. The same technology will be useful in rivers too
it is predictable and reliable, so has significant advantages over wind.
A guaranteed minimum power generation would presumably be very useful.
Don't tides happen everywhere there is a coast (which is a lot of places)? Or is this only effective in certain tidal conditions?
One thing that's relatively unique about the UK is that different parts of their coastline experience tides at different phases -- meaning with carefully chosen placement of different tidal energy plants, you can always have some of them operating near peak production. Click around https://www.tidetimes.org.uk and you can find places with high tide times happening at just about any time of day.
If you look at a map like http://www.bidstonobservatory.org.uk/wp-content/uploads/2016..., the best places to use tidal energy would be red areas with lots of white lines hitting the coast -- these would give you the highest-amplitude tides with the most opportunity for phasing. The UK has both.
Most regions have very small tidal ranges. That doesn't mean they have small tidal currents (think of fjords or straights for example), but it does make it more likely.
And in those fjords and straights, I reckon yhese solutions will compete with boat traffic.
To put this in perspective, less than 1% of the world's land area would be needed for wind turbines to power the current energy needs of the globe (according to NREL). So this is not a limiting factor.
KE = p^2 / 2m
Energy in the Moon's orbit: 5.7*10^45J
Energy in the Earth's orbit: 4.4*10^42J
So the lower momentum of the Earth (with a square term) and its (much) higher mass (Moon is 1.2% the mass of Earth) make Earth over 1000 times less energetic. So it's just the Moon that matters here.
Assume every joule extracted is coming directly from that budget and the moving water wasn't going to hit Scotland and turn some into heat anyway. 15.9 TW is average human energy usage.
5.7*10^45J / (15.9 TW * 1 year) = 1.14 * 10^25
So if we generated ALL human power from this method and every joule was taken from the Moon's orbital energy that would otherwise not be taken, we can spin the system down in just over a ten million billion billion years.
This is actually a bit more than I expected, though I knew it would be a lot from basic common sense of 80 billion billion tons moving at 1km/s. So maybe I've flubbed a few (tens of) orders of magnitude? In particular, the 1000:1 Moon:Earth energy ratio sounds plausible when I think about it, but it still was a bit of a surprise.
In any case, I think it's OK.
Edit, OK, so that was bunk, the orbital energy is 3.8×10^28J, so we can unbind the moon and donate it to Jupiter in only 65 million years.
EDIT: and can we also simultaneously slow down the Earth's rotation to have exactly 360 days per year? Fix the calendar once and for all.
Oh my god! That's an amazing idea!
Yeah, a few tens! Part of it is that you seem to have reinterpreted angular momentum as linear momentum. That's not dimensionally cromulent.
This one's free, KSR, sir.
I've read a lot of science fiction involving macroscale engineering on such levels, but I think even the most misanthropic science fiction writers have a hard time imagining a species that can start meaningfully affecting the orbital dynamics of their solar system but are clueless about possible negative side effects. By the time you're postulating such things, all the negative side effects that may leap to your mind involve energies many, many orders of magnitude smaller than the disruptions themselves, e.g., "oh no our satellite orbits", well, divert .000000000001% (I just hit some zeros, that's not calculated carefully) of the energy to fixing the satellite orbits. You're going to anyhow.
On a more amusing note, if you're interested in a counterexample to your direct claim, which involves another catastrophe that makes the worst predictions of climate change look like human paradise, I would recommend to you "The Nitrogen Fix" by Hal Clement. I won't spoil what the catastrophe is in case you might be interested in reading it, but Google will spoil it readily if you prefer.
When has that ever stopped greed?
In the interest of avoiding spoilers, I will merely advise anyone interested in a story with similar themes and content to read Signal to Noise and its sequel A Signal Shattered by Eric S. Nylund. You may know him from his work on the Halo franchise or other popular games. I don’t really know his other work, since I first discovered him via his original works.
edit: Kardashev scale
/s if not obvious
> Exponential growth is real
It’s really not. 99% of the energy used by humanity is still sunlight used to grow crops the same it’s been for thousands of years, and crop land use hasn’t been increasing exponentially. The majority of growth has been from efficiency gains not utilizing more energy.
Our ancestors realized irrigation and selective breeding allowed for more production from the same land. Fertilizer, better breeds, insecticides, meant more yield and automation meant less labor but the underlying energy input is unchanged barring increases in land under cultivation or the mouthes of livestock.
Instead many historic curves look exponential when you ignore the underlying population growth driving the whole thing and the recent reductions in fertility.
But I have no doubt the energy gained by gifting the Kardashians escape velocity would be scientifically significant.
The 2004 Indian Ocean earthquake and following tsunami shortened Earth's day by 2.68 microseconds. The energy of the tsunami alone was around 4.2E15 joules. Considering Earth's mass, radius and moment of inertia it would take ~2.9E26 joules to shorten the day by 1 minute.
It seems it really won't be an issue for a while.
In the same way, we're not running out of geothermal energy (a tiny part of the heat actually comes from the moon pulling magma around, the rest from radioactive decay and residual hit from when our planet was created). Technically more heat radiates out via our crust naturally than we'll ever need.
So, technically yes but not in a way that actually matters on the time scales we have left on earth, which technically will become a lot more hostile over time anyway. A billion years from now, things will be very much changed here. Minuscule loss of momentum in the moon's orbital movement will be the least of our concerns there.
Edit: although maybe it could facilitate transfer of angular momentum between Earth rotation and the moon's orbital motion.
It's very unclear to me that removing heat from the ground, reducing wind speed/pressure, and lowering tidal forces is guaranteed to never have catastrophic impact.
They do the same exact thing in terms of 'slowing wind down' and 'preventing the sun's energy from reaching the ground'.
This idea is understandable, but it falls apart for the same reason the wind turbine bird death concern does (the number of birds that have died due to humans liking windows is 1,000,000x the number that have died in turbines).
To a lesser extent, yes. However, power generating facilities are different in that they are intended to remove as much energy as possible, whereas sky scrapers etc are not.
But if it makes you feel better, all man made structures combined cover a small fraction of the earths surface people tend to be in areas with other people and thus it looks like we’re doing more than we are. NYC for example has 291x the average population density of the rest of the US and that’s including over a square mile devoted to Central Park.
Agriculture has a bigger impact because it cover so much land, but that’s offset by it being relatively close to nature.
I get your point, but a 1,000x+ difference in quantity cannot be ignored.
But like the other comment said, with solar you are not taking anything.
But solar panels do heat up the air around them more than vegetation would do.
See also, "Agrivoltaics."
Solar is just transforming light into electricity, i don’t think it’s removing any heat from the system unfortunately, unlike radiative cooling paint.
Now that we should be painting any tropical building we can with.
You're not removing anything, you're just transforming kinetic energy into electrical energy. Energy transforms, everything transforms on earth, as per the laws of physics. When you die, your body doesn't get "removed", it gets transformed into worm food. It's the cycle of matter and energy. "Yeah science Mr. White!"
I doubt human devices that capture wind and water wave energy are enough to negatively impact the climate in a meaningful way, considering how powerful nature is.
That's the second law, now you know what's up
You can't win, you can't break even, you can't leave the game
Cause entropy will take it all 'though it seems a shame"
-MC Hawking
Exactly what we used to say about industrial gas emissions.
Covering the ground in non transparent panels removes heat from the ground.
The side effects of solar panels is indeed a cooler ground underneath. Plants have difficulty growing in the shade.
Panels have a darker shade than most ground they are covering, so they might actually absorb more heat than the typical ground they are covering. They are distorting the local albedo.
I think for geocooling by solar panels shade, the effect is completely local and only surface deep. After all stone/ground is an insulator, and geothermal energy is considered renewable.
We all need to live with some calculated risks.
.. compared to taking energy and carbon from the ground, and changing the atmospheric composition enough to significantly change the temperature? Because that's the alternative to not-renewables.
https://cs.stanford.edu/people/zjl/pdf/tide.pdf is a pretty accessible entry.
I think that those assumptions are wrong in multiple ways and that reasonable estimates of the amount of tidal energy that could be extracted would lead to time scales where the risk no longer becomes relevant.
And as others have said, 1000 years is a hilariously wrong estimate.
It's better than oil (duh), and something that provides power when solar/wind can't is great (duh). I just wish we would give up on approaches that are basically "If we had a few million of these giga-ton structures all over the ocean, they would provide power equivalent to a few dozen nuclear plants"
There's a whole tirade in "Landman" about wind turbines not being green because of this or that thing[0], ending with the statement: "in its 20-year lifespan, it won't offset the carbon footprint of making it". These are just feelings (of the fictional character, but unfortunately ones adopted by real people) that are unconcerned with the facts that, no, the lifecycle analysis shows that wind turbines break even in 1.8 to 22.5 months, with an average of 5.3 months[1].
And I'm not qualified to say the tidal based solutions will never beat out Geo/Solar/Win + Batteries. In my informed but non-professional opinion, it seems like this avenue will never ever work at scale.
From everything I've seen, we have the answer, we're just stuck under the boot of old money oil barons. Solar + wind + geo (depending on the geographic area) for the majority of our power generation. Nuclear + batteries to smooth out the duck curve form the bottom, paired with more aggressive demand pricing & thermal regulations to smooth it out from the top. That's the answer. But lobbyist's going to lobby.
Mind you the market has tended to give up on tidal power too. The sea is a harsh environment, working there is expensive, and solar cost reductions have simply run over most of the competition. Scotland has seen quite a few innovative ocean energy companies launch a pilot, run it for a few years, then go bankrupt.
Meltdowns are tragic when they occur - but rare. It just gets a lot of press when a city of 50k gets deleted than when global ecosystems fail or a billion people die a decade earlier than they otherwise would due to pollution related helath issues.
Likewise, although it's absolutely true we're only talking about a few football fields of even the more voluminous low-level waste (high-level is about the size of one small block of flats), this is difficult to collect when it's a layer of dust spread over a few hundred square kilometres or dissolved in the seawater.
If one of the UK reactors had gone up like Chernobyl, the UK would have ceased to exist, not because of the radioactive kind of fallout but simply the economic fallout would have done it in.
Also I might just be misinformed but I thought nearly all of the radioactive waste from nuclear plants is already collected. It's not a collection problem, it's a storage problem. And a "what do we do when the energy company shuts down and stops maintaining their storage yard" problem.
Dungeness, would have included Dover.
Bradwell, the Thames. The Sizewells, it would have been Lowestoft and Harwich.
Torness, the Firth of Forth, blocking sea access to Edinburgh.
While this is not an exclusive list, and also I grant I'm not actually modelling what the fallout zone might look like when there's a coastline involved (is it better or worse? IDK), I ask you: which major international transit hub can the island of Great Britain do without? I'm sure they can be rapidly evacuated (being transit hubs), but how fast can the capacity be replaced elsewhere, how fast, and at what cost?
Consider that the UK barely had enough stuff in place just for the Brexit-related customs checks, which it saw coming, even though there was a global pandemic at the time that reduced/zero passenger on the same hubs. How much worse if any of these hubs becomes completely off-limits?
That plus the chronic[0] extra demand on the rest of the power grid. Ukraine had to keep the other reactors at the Chernobyl power plant itself running after the incident, just to avoid shortages.
A 2016 estimate said the overall cost of the Chernobyl disaster was US$700 billion, which is approximately [EDIT: not 97%, mixing dollars and pounds, see [3]] 72% of the tax revenue the UK collected in the tax year starting about when that report was published[1][2][3].
Regarding your point about collection of radioactive waste from nuclear plants, that's only the case for correct operations, not when they leak — or, in the case of Chernobyl, explode.
[0] the acute (sudden) part is fine as shutdowns happen at random anyway; chronic is the long-term.
[1] https://globalhealth.usc.edu/wp-content/uploads/2016/01/2016...
[2] https://en.wikipedia.org/wiki/Budget_of_the_United_Kingdom
[3] https://www.wolframalpha.com/input?i=700USD+in+GBP+in+2016
You're taking 30 years worth of expenses and comparing them to the UK tax intake for one year. I am pretty certain the USSR didn't pay for all that up-front.
So $700b over 30 years is about $23b/year. The UK gov budget for the year you selected was about $1045b[1]. So if we are to take your Chernobyl example, it's about 2% of GDP per year. That is roughly half of what was spent on the second-smallest sector of the budget - "Public order and safety". That is a lot of money! But you're implying it would cause the collapse of the UK altogether.
As a comparison, during the 07/08 financial crisis the UK government bailed out the banks to the tune of $185b and managed to not collapse...
[1] https://www.gov.uk/government/publications/budget-2016-docum...
Didn't pay all of it ever, that's also the damages of other affected nations after the collapse of the USSR.
So, there was a de-facto if not de-jure default on that cost.
> As a comparison, during the 07/08 financial crisis the UK government bailed out the banks to the tune of $185b and managed to not collapse...
It also owned some of the banks as a result (I was personally affected by this, LLOY shares), it wasn't just a pure cost.
I do not have sufficient grounding in any of the relevant fields to create such a simulation, so I'm limited to drawling circles on a map around the reactors, seeing what's inside, and making a best-guess as to the consequences informed more by world news than anything more precise.
The weirdly evasive language just undermines the rest of your points and makes you look a bit ... dishonest?
You make that sound easy. Finnland did it, France did it.
But for example Germany started to look for one in 1976, failed, rebooted in 2017 and the current estimate is we might one one in 2060.
Thermal plants like coal and nuclear need cooling water, the output of which ends up in the sea too
The vision now might not be to fill the sea with these turbines. But if it turns out they can be made cheaply and deployed cheaply, easily broken machines that nobody will take responsibility for will definitely be littering the oceans by the millions.
And from everything I've seen/heard, tidal based solutions are just fundamentally incompatible with their product. Keeping sensitive metalic moving parts in saline solution exposed to the sun for years on end - paired with other random things like boating accidents or marine life - it's a non-starter. Constructing these things creates pollution. If it's lifecycle impact is less than oil's, great, I just don't believe we'll ever get to a state where it's better than oil AND (solar/geo/wind) + Batteries.
They may not be a good commercial idea due to the maintenance cost (hence this article) but the idea that they would pollute the seas and therefore we should burn oil & gas instead completely idiotic.
The problem here is you have a large body of water that is a huge and significant nursery for fish, and the best place for the turbine is where the water narrows.
If the turbine is a barrier to the fish, (and who knows?), then important fisheries may well collapse
This is an objection that needs to be taken seriously and investigated, so I was disappointed that the article did not address effects on marine life.
Personally I think that the turbines and marine life can co-exist, but we need facts, not reckons
The installation in the Pentland Firth is a fundamentally different category as it is installed in open water (albeit in a firth or channel) which is much less environmentally impactful and has 2-4 orders of magnitude more suitable sites globally.
Firstly sea water is corrosive, plus if you add all the sand and other particles that are in there it becomes abrasive as well.
BUT
the tide also reaches speeds of 30kmh (18mph) twice a day.
Still provides power today.
Solar, wind, and storage can solve most of our energy needs, TODAY, but look at how it’s being treated.
To be pedantic, a lot of wind turbines are placed out at sea.
> It’s very hard to take what is essentially a wind turbine normally found on land and put it under water
With that context your comment looks pretty silly, no?
Because we are not "allowed" to ask these questions, I suspect these environmental efforts are just the vehicles to make money for certain political groups. Just as "freedom on the march" is a vehicle to make money for other groups.
Then you essentially getting a consensus view on the topics. I question how much of an information value, knowing the consensus view, brings to the reader.
It’s good to know the consensus view, sure. But you also want to know the actual situation, even if it’s different.
I don’t feel “victimized” by this, just more realization of what am I getting. I definitely not consider this a news anymore, more of a consensus indicator. As such, it has value.
Tidal power only works where the geography is right. A bay with a choke point to the ocean, like this one, is needed.
There are plenty of places where water is naturally under pressure, tidal power is definitely something we should be pushing for more as a species.
I believe they specifically designed it to simplify maintenance
> The obvious concern that most people might guess will be dangerous and damaging to [swimming] wildlife are the spinning blades themselves. While large white spinning [turbine] blades rotating [below] the horizon or in an advertisement seem bucolic, restive, and like the perfect green energy source, the fact is that the tips of the blades can be spinning at up to 200 miles per hour. Those speeding blades can act like a giant blender for large [fish] such as [tuna] and [whales] which fly around the commercial [water] turbines and chop those [fish] up. Biologists have found that even small species of American [fish] regularly get killed from the spinning turbines of commercial [water] turbines.
/s
These turbines have a diameter of 18m and a speed of 8 to 20 rpm. So a tip speed of 7.5 to 19 m/s - about 27 kph to 68 kph. I guess that's enough to hurt a whale. Although interestingly the water speed due to the tide in this channel is up to 5 m/s - so maybe it's too turbulent for whales anyway. Do whales like fast flowing water?
also, you, the MAGA-hallucinations against windpower are contemptible lies AND they have nothing to do with this single underwater turbine.
https://public.nrao.edu/ask/what-happens-as-the-moon-moves-a...
