Since the number 1.2MW didn't mean much to me, modern on-shore wind turbines seem to supply 3-4MW and offshore ones 8 - 12MW.
But this seems a lot easier to transport and install compared to cranes and the nightmare of navigating turbine blades on trucks through places. And if these hold up to water and don't cause too many problems for wildlife, there would be a lot less discussions about these "messing up my skyline", while tapping a new source of energy.
True, but they fly up where the wind is a lot stronger. Plus being much smaller means they might be cranked out in large numbers by a factory, which would make them relatively inexpensive, and also they don't have the major shipping problems that onshore turbines have.
They are more expensive but still cost effective (i.e. cheaper than burning fossil fuels or nuclear power). And winds tend to be more predictable and stable on the ocean. So, the capacity factor is better. And you are right that off shore wind is a lot less controversial. More importantly, it's way less hassle and risk. There are no NIMBY's blocking it. There are no complex land ownership issues to resolve. Magic wands to make all that go away sadly don't exist. So, there's very little land where you can just decide to plop down a few hundred wind mills without getting bogged down in years of bickering with the locals, sorting out all sorts of complex issues, etc.
Also, out on the ocean there are no roads to navigate so moving big/heavy things around is a lot easier to do. All you need is ships. Transporting a blade that is over a 100m long over land is hard and expensive. The infrastructure just isn't ready for that. Off shore wind mills can be bigger than onshore wind mills for this reason. Floating offshore wind is now also becoming a thing. This will unlock areas further away from the coast.
Mass producing, mostly pre-assembled wind mills and shipping them out is a scalable business. Companies have been doing this for a few years now and it's working. They are getting good at it. They are making incremental improvements and learning ways to improve things. This learning effect is very real. There's no shortage of suitable spots to place these things. It's more a matter of how many GW do you need and how expensive is that going to be?
How do you feel about offshore wind? It seems like a potent power source, each one can produce several MW of power. If we need 1TWh we need a few hundred thousand turbines.
> modern on-shore wind turbines seem to supply 3-4MW
That sounds like the very largest of the most recent wind turbines. I think most of the in-production wind turbines people are used to seeing these days are closer to the 2 megawatt range.
As turbines get larger, not only do the costs go down, but the reliability of supply goes up. It becomes more economical to place them out at sea, where winds are more reliable, and the size allows them to run more effectively off low speed winds. These turbines are claiming 60%+ capacity factor, compared to 20-30% for smaller, onshore turbines.
The UK is already up to about 15% of its electricity from wind right now, these developments will open that up significantly more. Obviously at high levels of penetration there are going to be issues, we'll just have to see how far we can go, but even 25-40% of electricity would be a huge contribution.
Combine that with the new and existing nuclear, another 15%, some biomass and tidal lagoons, with the rest from gas (which produces half as much CO2 as coal) and it will go a long way towards meeting the UK's 80% CO2 reduction target from 1990 to 2050.
Not even remotely, off shore turbines are much, much more efficient. Newer turbines already have capacity factors of over 40%, newer off shore turbines can exceed 50%.
Big turbines are big because of one simple thing: efficiency. It takes a lot less in terms of materials and space to make a single 8 MW turbine than it takes to generate the same amount of power with a large number of smaller ones.
Yes, if they go down you lose a large amount of capacity in one go, but that does not weigh against the cost of a large number of smaller turbines that will go down much more frequently with smaller losses (they still need to be repaired). Though the cost to repair them will likely be lower per instance the people doing the service still have to be called out.
I love this google project and I'm really curious what will come out but what with wind being my life-long side interest and having seen a large number of fantastic designs come with a hurricane of fanfare and go again without a breeze I'm not going to bet on this until there is much more hard data to compare to 'conventional' systems.
Three blade conventional machines are anything but, they're engineering marvels with a ton of materials science behind them, it took nearly 40 years to go from the 10 KW prototypes at Petten (in NH, NL), to the giants you see today. That's a lot of R&D invested over a very long period of time.
Now these kites can leverage some of that knowledge and they no longer have to validate the concept of windpower for regular consumption, that trail has already been blazed so they should have an easier time of it.
Here's to hoping that it works, and that it won't end up next to 'windtree' or the 'windbelt' or a hundred other revolutionary wind technologies that ended up being stillborn.
It's certainty easier to haul 12 Kites to site than props for a 198 meter wind turbine. I'm thinking deployment might be easier as well. Plus, if one kite breaks you only lose part of the electrical output as opposed to a large machine going off line. I wonder if hauling the thing down by line and repairing it on the ground might be easier than climbing up a tower. I would think so but could be wrong. Of course a larger fleet of individual machines probably means more frequent (smaller) repairs so there is that. How high do birds fly? Could these maybe solve the bird killing problem traditional wind turbines have had?
I wonder if that's really the right direction to go. Admittedly, the gains in output are impressive for comparatively small increases in size (I think there's a cubic growth somewhere). But the main problem with offshore wind energy currently seems to be installation. It might be economically better to produce more small turbines and install them much more efficiently instead of doing fewer, more complicated installations. One could, for instance, create 6MW floating in a large factory near the cost turbines and literally ship them to their location.
By far the most wind turbines have been built on land and for good reason: it's much cheaper. As long as there is space/not too many people complaining it makes more sense to build on land. Not sure exactly but on land installed wind is probably ~10x the installed capacity offshore. However on land turbines are pretty much maxed out at about 7,5MW, due to logistical difficulties of getting larger blades, towers and nacelles transported over the road. These limitations don't apply to offshore sites, so the up-scaling continues. In the last few years typical offshore turbines have grown to about 9MW, but that is not the limit. Within a few years we should see 12-15MW turbines being installed, which should bring the cost down. Combined with the better wind conditions offshore (at least around the North Sea) offshore wind may become cheaper than expanding on land.
This seems pretty cool! I suspect they don't get quite as much energy per m^2 as a traditional turbine, but if they're cheaper to produce and maintain (it should be possible to lower the blades to sea level) then I can see a case for it.
The biggest turbines stopped being land based years ago. Onshore wind caps out around 6 MW, while offshore wind is pushing 16 MW. There's just no practical way to handle these huge turbines (and their massive blades) onshore.
Large wind turbines are interesting, because due to the lower friction from the ground winds are stronger up there so the capacity factor is appropriately higher.
They also scale in power with the swept area, so it pays to make them even larger.
IIRC the current state of the art is 14MW with a 60% capacity factor and that is not the manufacturers' last word.
Exiting times ahead for wind power because while it's still intermittent, it gets built so much faster than nuclear.
> a 2MW "mast" that can compete with today's technology is going to be crazy tall
I wonder about how the power generated scales as the size increases. It's 100W at 9', and 4kW at 40'. At ~4.5x the height there's 40x the power generated. It's foolish to assume the same exponential gains apply continuously, but given the reduced footprint, is it possible that laying out five of the 40' units is sufficient for 2MW (edit: wait, I totally fudged that math, so this point doesn't really make sense), and at that size, you might be able to just use a bucket truck for maintenance?
We shouldn't assume just because it's a new technology that the same problems don't need to be addressed, but we also shouldn't assume the same problems need to be addressed in the same manner. This article doesn't do a lot to explain the details, and as you've explained I've heard that maintenance of wind turbines is where a lot of the money to run wind farms goes, so it's interesting to look at new designs from the standpoint of how it may radically change maintenance, not just scale with the current methods.
That said, you obviously have more experience with this than me, so hopefully you'll be able to provide some more perspective on the ideas here.
P.S. Something that occurs to me is that I have no idea how they stop the oscillation caused by the wind for maintenance on those. You can lock the turbine blades, but I'm not sure how you prevent something made to oscillate naturally in the wind from doing so, easily.
P.P.S I totally messed up my math because I wasn't thinking straight, 5x4kW is not even close to 2MW. I'll leave this here for historical purpose, but much of my point lacks any weight now...
Sounds just about right sized to get off-shore grade wind turbine blades to remote inland hills. The benefit of larger turbines is even bigger inland than off-shore, but inland is severely limited by transport, because (unlike the tower) those blades can't realistically be built from subassemblies on-site.
But this seems a lot easier to transport and install compared to cranes and the nightmare of navigating turbine blades on trucks through places. And if these hold up to water and don't cause too many problems for wildlife, there would be a lot less discussions about these "messing up my skyline", while tapping a new source of energy.
Quite interesting and cool.
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