This is a good read. The difficulty of transporting large wind components over land is one reason that onshore wind turbines have lower maximum capacities vs. offshore turbines. The largest onshore turbine is 5.3 megawatts [1] while the largest offshore turbine is 9.5 megawatts [2]. Transporting super-large components by sea is easier -- no tunnels, bridges, or winding roads to worry about.
Very tall turbines tend to improve capacity factor and project economics by tapping steadier winds found further away from the ground. For onshore projects, at least, that benefit is in tension with the more difficult transport and assembly logistics noted in this article.
Solar has the logistics edge in that all of the components for a solar farm are much smaller and weigh less. Even the largest individual solar modules are under 40 kilograms each. Racking systems are also assembled out of smaller pieces. No oversized loads need to be transported to the solar farm site. There are more truckloads of components for a 400 megawatt solar farm vs. a 400 kilowatt farm, but the individual components and trucks need be no larger.
Vestas is heavily marketing their 5.6 MW platform now, and at least sending preliminary sales and design information to clients. We're probably a couple of years out from installing any that big though.
The real surprise is how fast capacity has jumped. We went through a period of rapid size increase, then a decade plus plateau around the 2 MW mark, and now a very rapid rise to 4+ MW onshore.
It's true we get to better winds higher up, but we also see some significant cost advantages related to building fewer turbine foundations, needing to erect fewer individual units and having relatively fewer miles of site road and collection to achieve the same production.
Right, but the Haliade-X is still under development. It's supposed to be available in 2021. I linked to the largest turbine model I knew of that is already in commercial service.
the generator in the wind turbine is not generating at 66 kV. There is a transformer in the base of the turbine to step the voltage up to 66 kV. A 10 MW generator is typically at 6.9 kV, although could be up to 13.8 kV.
In NL we have a whole bunch of those large Enercon units near the village of Urk. Well worth a stop if you're ever on A6, it is an amazing sight especially up close.
Given the huge promise of terrestrial wind farms, it seems like someone is right now figuring out a way to either a) fabricate them on-site, or b) fly the parts in via drone or dirigible.
GE is definitely working on this. A friend of mine was telling me they have pretty elaborate setups for welding or connecting the pieces of the blades while out in the field.
I have driven alongside trucks carrying single turbine blades on midwest highways many times and I can tell you many people would be very uncomfortable seeing something even larger flying across the countryside.
Building "on-site" is tough because the "sites" are by definition scattered around, often in the countrysite with little infrastructure. On one site you only have a handful of turbines to install.
Flying large objects is challenging.
There have been attempts to transport large cargo with zeppelins, but it's more of a failure story of German industry politics [1].
I don't know the chemistry behind it, but it's interesting to hear the counter argument that it will actually create more polution to build a solar panel relative to its lifetime. Would love to read more.
He's mostly correct up until point 9. Then he goes off the rails. I don't know where he got the idea that silicon manufacturers dispose of silicon tetrachloride in oil wells. I just searched "silicon tetrachloride" "oil well" and he seems to be the only person on the Web advancing that theory.
It sounds like a somewhat garbled retelling of this widely reported story from 2008 about unscrupulous Chinese manufacturers dumping silicon tetrachloride:
"Some Chinese “clean energy” companies produce a toxic hazard"
Facilities in South Korea, Japan, Germany, and the United States purify silicon by the same process and do not dump silicon tetrachloride. They recycle silicon tetrachloride into more trichlorosilane, or turn it into other salable silicon derivatives. Dumping silicon tetrachloride on the ground is no more the norm in the silicon industry than adding melamine to milk is the norm in the dairy industry.
EDIT: Here's a products page from Mitsubishi Polysilicon, which manufactures high purity silicon in the USA. They sell the purified silicon tetrachloride for making fiber optics:
The point I wrote is not merely that building solar creates pollution, but relative to its lifetime it may do more harm than good – in its current state of the art. In other words, a lot of dirty to get a little clean.
Someone on the site asks about helicopters and I wonder the same thing. I know helicopters are hellishly expensive to use, but they are used occasionally - eg for ski lifts.
>The largest wind turbines can weigh up to 700,000 pounds fully assembled and typically require around 10 loads to transport.
so, average speaking the components are on the scale of 35t/each. The current helicopters top at about 20t payload, so could be used only for some smaller parts. That one https://en.wikipedia.org/wiki/Mil_V-12 could have done more jobs here. Or it is a new and shiny market for airships (or some kind of hybrid with airship)
Stupid question but is there a market for lots of smaller wind turbines? What’s the efficiency like vs. one big turbine? Is there something like a solar farm with modular panels, but for wind?
This has a strong propaganda smell - he fails to mention the use of fossil fuels in production of nuclear fuel; he also fails to mention the use of concrete and steel in the construction of nuclear power plants.
I wish you could magically get power out of a lump of radioactive metal that you found lying on the surface of the ground, in the real world you have to build infrastructure to harness it.
Very tall turbines tend to improve capacity factor and project economics by tapping steadier winds found further away from the ground. For onshore projects, at least, that benefit is in tension with the more difficult transport and assembly logistics noted in this article.
Solar has the logistics edge in that all of the components for a solar farm are much smaller and weigh less. Even the largest individual solar modules are under 40 kilograms each. Racking systems are also assembled out of smaller pieces. No oversized loads need to be transported to the solar farm site. There are more truckloads of components for a 400 megawatt solar farm vs. a 400 kilowatt farm, but the individual components and trucks need be no larger.
[1] https://www.genewsroom.com/press-releases/ges-largest-onshor...
[2] https://en.wind-turbine-models.com/turbines/1605-mhi-vestas-...