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Underwater turbine spinning for 6 years off Scotland's coast is a breakthrough
- davedx 1y agoI did some reading about this yesterday: * 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
- deleted 1y ago[deleted]
- mushufasa 1y ago> * The Global Technical Potential (in TWh/year) is 1/10th of offshore wind 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.
- gmueckl 1y ago1% of the world's land surface is massive! That's about 1.5 million square kilometers. That's more than 4 times the land area of Germany or apparently about as much as the entirety of the built up area on Earth.
- tonmoy 1y agoFor reference the Sahara desert is 9.2 million square kilometers (obviously covering the entire desert in turbines is impractical, but we might be able to come up with 1% “useless” land if needed)
- bryanlarsen 1y agoBut that's non-exclusive use of 1% of the surface. Land under wind turbines can and is actively used for farming et al. The actual area that's prevented from other use is much less than 1%.
- CGMthrowaway 1y agoSo we would need to cover 4% (1% * 10 GTP * 30% land / 70% water) of the ocean to power the world? Seems like a lot
- ksec 1y ago>* 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.
- dmix 1y agoSouth Korea was going to build a large one but canceled it due to the marine life threat. One way they try to fix it is by having a safety mechanism that turns the blades off when marine life passes through but this increases operating costs on something that is already high maintenance.
- graemep 1y agoIt will be a far higher proportion in the countries where there are suitable locations. it is predictable and reliable, so has significant advantages over wind.
- mike-the-mikado 1y agoQuite possibly, with a suitable distribution of sites around the UK coast, the total power generation might be nearly constant over time. A guaranteed minimum power generation would presumably be very useful.
- libraryatnight 1y ago"Tidal energy is valuable but geographically constrained" Is this really a negative? Can it not be simply viewed as a boon for places where geographically reasonable? I live in Arizona, I'll not be upset when left out of tidal energy - I've got solar and a sunshine surplus.
- adgjlsfhk1 1y agothe hard part with geographically constrained sources is that they have a harder time getting economies of scale. solar works everywhere and is really easy to install, so the market cap is massive, leading to corresponding increases in production efficiency.
- dmurray 1y agoAnd importantly, China isn't on the list of places this works, and China is the only place in the world for generalist manufacturing at scale.
- insane_dreamer 1y ago> Tidal energy is valuable but geographically constrained Don't tides happen everywhere there is a coast (which is a lot of places)? Or is this only effective in certain tidal conditions?
- meatmanek 1y agoTides happen everywhere, but not to the same extent and not always at useful times. If your peak production times don't line up with peak demand times, then you need expensive energy storage. (This would change with the phase of the moon, so sometimes you'll get lucky and sometimes you won't.) 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 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/2016/08/modelling-fig3.jpg 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.
- 317070 1y agoThe issue is clarified with a map like this: https://i.redd.it/rontertecjqd1.jpeg https://i.redd.it/rontertecjqd1.jpeg 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.
- rocqua 1y agoNaively, you'd expect the tidal current to be proportional to (tidal range/water depth). Which causes that map to be a lot less informative.
- insane_dreamer 1y ago
- lostlogin 1y ago> because it generates powers during high/low tide, 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.
- worik 1y ago> * Tidal energy is valuable but geographically constrained 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
- xattt 1y ago> Canada 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.
- dmix 1y agoPlus a newer one off Vancouver island BC shut down after a couple years because its operating costs made it economically infeasible. Had to get fixed and upgraded a few times. Which I why the maintenance thing in the headline is probably relevant.
- ethbr1 1y agoThe Annapolis looks like a fundamentally different design: direct turbine driving instead of low-speed / high-torque windmill design. https://www.youtube.com/watch?v=pxCPXLv--U4&t=71s https://www.youtube.com/watch?v=pxCPXLv--U4&t=71s
- papercrane 1y agoYes, the Annapolis station was conceptually very much like a hydroelectric dam generator. When the tide was coming in sluice gates were opened to allow a reservoir to fill, then when the tide was going out the water was sent through a high-speed turbine. 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.
- NotAnOtter 1y agoAs cool as this sounds, I'm not sure I'm as enthused with stuff our oceans full of more tech, which inevitably will wear down, break, and pollute. 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"
- pjc50 1y agoPeople aren't terribly keen on what happens when nuclear plants inevitably wear down, break or pollute either. 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.
- NotAnOtter 1y agoPeople are broadly misinformed. Nuclear plants release significantly less radiation than coal based plants, as an example. They do create a lot of waste that we currently don't know how to process, but the quantity is actually shockingly small in the context of a global issue. We're talking several warehouses. Not millions, not all of California. We can just pick some cave in northern Canada or central sahara and bury it there, it seriously isn't that much. It's better than where we currently store the waste which is basically the ocean & clouds. 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.
- ben_w 1y agoWhile all that is true, the problem is specifically how much it can cost in the worst case. There's only been one Chernobyl out of about 400 reactors, and its cleanup cost amortised over all those reactors makes a surprisingly small difference to the cost of electricity, but also Chernobyl was bad enough to be considered a significant part of the collapse of the USSR. 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.
- sneilan1 1y agoNot to sound like a crazy person, but, does taking energy from tidal waves mean taking energy from the momentum of the earth itself? I read a long time ago somewhere that if we extract enough tidal energy, the earth's rotation could slow down somehow. Obviously as a layperson on this matter I'm not that well-informed but just curious of the possibilities if anyone knows.
- nbf_1995 1y agohttps://cs.stanford.edu/people/zjl/pdf/tide.pdf https://cs.stanford.edu/people/zjl/pdf/tide.pdf
- brian_spiering 1y agoGiven the current rate of development, it probably won't be an issue for a while.
- aeve890 1y agoWhy the downvotes? 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.
- HPsquared 1y agoConservation of angular momentum says no. Energy, momentum and angular momentum each have their own conservation laws. Edit: although maybe it could facilitate transfer of angular momentum between Earth rotation and the moon's orbital motion.
- bobmcnamara 1y agoThere are conversions between each.
- nachexnachex 1y agoThat's correct, while clean it'd be a mistake to classify it as "renewable". https://cs.stanford.edu/people/zjl/pdf/tide.pdf https://cs.stanford.edu/people/zjl/pdf/tide.pdf is a pretty accessible entry.
- nick238 1y agoMaybe these are the windmills that drive the whales crazy? To paraphrase wind-watch.org (sounds non-partisan) > 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
- bad_haircut72 1y agothis feels solvable with a cage around like you have on every pedestal fan?
- leoedin 1y agoDid you just post a wind-turbine criticism? 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?
- vpribish 1y agothat reads as nonsense. it's mixing wind and water, and all those missing words indicate that it's the product of a broken mind. also, you, the MAGA-hallucinations against windpower are contemptible lies AND they have nothing to do with this single underwater turbine.
- callamdelaney 1y agoMy intuition is that these will be moving much more slowly than that. The turbines that they refer too are usually high pressure ones designed for generating energy downstream of a huge body of water like a resovoir.
- barbegal 1y agoOnly 1 of the four turbines has been able to operate for 6 years without pulling it out the water. The other 3 have needed costly maintenance https://www.waterpowermagazine.com/news/sae-secures-loan-for-turbine-redeployment-at-meygen-9599438/ https://www.waterpowermagazine.com/news/sae-secures-loan-for... It's a nice idea but costly compared to solar even in places like Scotland.
- badestrand 1y agoI would love to see a complete cost comparison with solar. 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.
- theptip 1y agoAlso there is theoretically power in the GW range to be harvested here (specifically, Scotland’s tidal flows), so it’s worth investing a substantial sum to figure this tech out.
- mlyons1340 1y agoTexas’ capacity was 113000 MW yesterday so 1.5MW doesn’t seem significant. Am I understanding this wrong? https://www.ercot.com/gridmktinfo/dashboards https://www.ercot.com/gridmktinfo/dashboards
- deleted 1y ago[deleted]
- saberience 1y agoWhy are you comparing a single turbine in Scotland to the entirety of the state of Texas's supply (thousands of turbines)?
- mousethatroared 1y agohundreds of thousands.
- JR1427 1y agoOut of sight, out of mind...
- KaiserPro 1y agoOne thing is not immediately obvious is just how hostile that area is. 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.
- amelius 1y agoCaution, by harvesting tidal energy you're tapping into the potential energy of the Moon, making it move closer to us at an increased speed.
- lostlogin 1y agoSurely taking energy from it would make it move further away?
- thebruce87m 1y agoDoesn’t the moon move away from us? https://public.nrao.edu/ask/what-happens-as-the-moon-moves-away-from-the-earth/ https://public.nrao.edu/ask/what-happens-as-the-moon-moves-a...
- sgt101 1y agoWhere I live there's a tidemill that's been running for 850 years. Still provides power today.
- octaane 1y agoSounds like they need to get the quality control down pat if only 1 out of 4 of the turbines achieved this goal - still a promising milestone, though.
- standeven 1y agoThe real problem: if this technology is viable, it will immediately be attacked with disinformation campaigns (“but it kills dolphins!”), lobbying against it, government red tape, and tariffs. Solar, wind, and storage can solve most of our energy needs, TODAY, but look at how it’s being treated.
- worik 1y agoWe have debate around this in New Zealand 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
- Animats 1y agoNice. Tidal power only works where the geography is right. A bay with a choke point to the ocean, like this one, is needed.
- alt227 1y agoOr the mouth of an estuary, or an underwater shelf where currents are forced up or down, or any stretch of water with sufficiently high tidal ranges etc. 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.
- robotnikman 1y agoI wish they provided pics of one underwater. I love stuff that invokes a feeling of submechanophobia
- KolibriFly 1y agoYeah, there's something weirdly mesmerizing and terrifying about giant machines lurking underwater
- KolibriFly 1y agoThe ocean is brutally unforgiving, and until now the skepticism around durability has been justified. But if projects like MeyGen can show that tidal infrastructure can go the distance, it could unlock a huge untapped energy source
- edarchis 1y agoThey're not exactly the same thing but for comparison, France has the Rance Tidal Power Station that has been producing 250MW for 45 years. South Korean made a more powerful one at 254MW. This pilot produced 4.5MW when all 3 turbines were operating normally.
- dominicrose 1y agoThis project is interesting but all comparisons are fair with the end in mind, which is the cost per MWh or per "home" over its life. If you need 55 of those to produce 250MW you'll have to multiply the costs by 55 as well. Power also has to be available all the time, when there is no sun, no wind, no waves, etc. Nuclear and gasoline are sadly the top picks because of energy density (and in the case of gasoline also portability).
- closewith 1y agoRance and Sihwa Lake are different beasts as they require sea walls or dams, which are immensely more expensive and environmentally damaging, and have extremely limited suitable sites worldwide. They would never be built now (Sihwa is only 15 years old, but the seawall was built in 1994). They are essentially low head hydro installations fed by the tidal range. 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.
- alex_duf 1y agoSee also the Scottish company Orbital Marine Energy with their really cool floating design: https://o2-x.orbitalmarine.com/ https://o2-x.orbitalmarine.com/ I believe they specifically designed it to simplify maintenance
- sparsely 1y agoCurrent energy sources are ~all either from solar radiation (indirectly for fossil fuels) or nuclear fission. Tidal energy is cool because it is to a rough approximation from neither of them!
- ppkkK 1y ago[dead]
- Cthulhu_ 1y ago> It’s very hard to take what is essentially a wind turbine normally found on land To be pedantic, a lot of wind turbines are placed out at sea.
- smcl 1y agoThe full quote is: > 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?
- adammarples 1y agoThey are still often found at sea. It might have been better to write it's very hard to take what is a wind turbine normally found above water and put it under water.
- bilsbie 1y agoAren’t we just picking up Pennys when solar and wind are available?
- remus 1y agoBecause water is pretty dense, you could in theory get a lot of energy from a relatively small tidal power installation which could be an advantage in some circumstances.
- Hnrobert42 1y agoIt will be interesting to see how the right disparages this form of non-fossil fuel based electricity generation.
- 93po 1y agoits a visual blight for scuba divers everywhere. it kills millions of fish. the wave patterns caused by the turbine cause chronic headaches for miles. the production process for the turbine actually creates more carbon emissions than just burning the equivalent of coal for 20 years
- g42gregory 1y agoWhat do these turbines do to Marine life? Fish, dolphins swimming next to the spinning blades. Krill, other micro marine life in the water, disrupted water currents affecting every forms of life? 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.
- BiteCode_dev 1y agoWho said you were not allowed to ask these questions?
- g42gregory 1y agoDownvoting that you can observe in real-time.
- BiteCode_dev 1y agoI downvoted you because you played victim, not because of your opinion on energy production and ecology. I assume many did the same.
- g42gregory 1y agoThat’s fine in this case, but keep in mind that any article questioning climate change will be downvoted because it does not align with majority of HN views. It goes for other topics as well. 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.
- ge96 1y agoRecently saw this design where it's a ball going up and down with a chamber inside, wonder how that will fair out https://www.youtube.com/watch?v=Q7Pmgq2JKbI https://www.youtube.com/watch?v=Q7Pmgq2JKbI