6MW offshore wind turbine - build me 300x please

AI Thread Summary
The discussion centers on a 6MW offshore wind turbine with a rotor diameter of 120m or 154m, featuring a direct-drive alternator without a gearbox. Dong Energy has ordered 300 units for €2.5 billion, highlighting the economic potential of offshore wind power despite high initial costs and maintenance concerns. Comparisons are made with nuclear power, emphasizing the lower equipment costs of wind turbines, but also noting the need for backup generation during low wind periods. The feasibility of deploying large numbers of wind turbines in states like Florida is debated, considering the state's energy demands and existing infrastructure. Overall, while offshore wind presents a promising energy solution, challenges such as installation costs and reliability remain significant.
Enthalpy
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Nice toy... :!)

A recent offshore wind turbine. 6MW peak power, the rotor has 120m or 154m diameter :-p

The alternator rotates at the blades' speed, without a gearbox... With D=6.5m, it uses permanent magnets, its stator must be actively cooled, and the nacelle weighs 200t.

Still not my electrostatic alternator, but it surely is a mere matter of time.

Some literature (zorry for ze languich):
http://www.windpowermonthly.com/go/enews/article/1133700/ (English)
http://www.energy.siemens.com/hq/pool/hq/power-generation/renewables/wind-power/wind%20turbines/6MW_direct_drive_offshore_wind_turbine.pdf (English)
http://de.wikipedia.org/wiki/Siemens_SWT-6.0
http://www.siemens.com/press/pool/de/feature/2012/energy/factsheet-6mw-d.pdf
http://www.siemens.com/press/pool/de/feature/2012/energy/factsheet-b75-rotorblatt-d.pdf

Dong Energy meant this was exactly the tool they wanted, because they ordered 300 of them for 2.5G€ :biggrin:

Let me estimate... The manufacturer alleges 23*106 kWh a year, but 44% of the peak power must be optimistic even offshore. Say 1/3 of the peak power (instead of 1/4 on land), it's still 600MW mean power for 2.5G€ acquisition cost. Thereafter, raw material is free, maintenance limited, and accidents have consequences on the turbine only.

Compare with my favourite punch-bag, the EPR: 1600MW peak power or 1200MW mean (or zero dot nothing watt if things continue as presently) for presently 8.6G€ acquisition cost before the next increase and the penalties, plus fuel, maintenance, dismantling, 240,000 years protected storage, and disasters... well, you know.

The wind is turning.
 
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Nice, but you are comparing an equipment cost vs an installed cost.
 
Enthalpy said:
...Dong Energy meant this was exactly the tool they wanted, because they ordered 300 of them for 2.5G€... Thereafter, raw material is free, maintenance limited,
Offshore wind maintenance is fairly expensive last I looked. As Russ points out that cost does not include installation. Nor does it include the cost of the baseload generation source to run when the wind idles.

and accidents have consequences on the turbine only.
And possibly for those depending on the power during an outage.
http://www.sunwindenergy.com/news/cable-damage-british-offshore-wind-farms

Compare with my favourite punch-bag, the EPR: 1600MW peak power or 1200MW mean...
Capacity factor .75? Nuclear runs over 90% CF in the US.

for presently 8.6G€ acquisition cost before the next increase and the penalties,...
So €7.1/W installed nuclear versus €4.2/W for the Siemens turbines, equipment only.

...The wind is turning.
Maybe. Maybe not.
 
Given that a state like Florida has something like 60,000 megawatts of generation
http://www.aee.net/index.cfm?objectid=A8DAB910-6150-11E1-B6F9000C29CA3AF3
that's ten thousand of your wind turbines assuming the wind is blowing hard enough to run them all full tilt. At more realistic 20% output it's fifty thousand of them. Just for Florida.

So wind power is an interesting tinkertoy and talking point for politicians, in my opinion.

Where it might make some financial sense is atop the Rocky Mountains west of Denver where the wind howls all winter long - but offshore units are too big to fit through the I-70 tunnels so you can't get the real moneymaker units up there. About the biggest thing you can get to where there's great wind is a GE 3.5mw.
Now that's not such a bad idea - there's existing transmission lines leaving Denver crossing the divide , so it'd be plug&play .
But it looks like the tax incentives to build them are uncertain at best.old jim
 
jim hardy said:
Given that a state like Florida has something like 60,000 megawatts of generation
http://www.aee.net/index.cfm?objectid=A8DAB910-6150-11E1-B6F9000C29CA3AF3
that's ten thousand of your wind turbines assuming the wind is blowing hard enough to run them all full tilt. At more realistic 20% output it's fifty thousand of them. Just for Florida.
...

That might be a little too conservative. If Florida is like the rest of the US, then it uses only half its capacity on average. And the average capacity factor for wind is over 30% onshore, greater yet offshore. So 17,000 6MWpk towers might do on average, not that Fl would ever tolerate that onshore.

There'd still be times when the wind dips coincided w/ the demand peaks, so there'd have to be a lot backup fossil generation (gas I suppose).
 
Why look at the power needs of Florida alone.

Here is a link to a recent story about powering the eastern seaboard of the US with offshore wind farms:
http://usnews.nbcnews.com/_news/201...with-144000-offshore-turbines-study-says?lite

That's right, only 144,000 wind turbines of 5 Mw capacity and it's all FREE!
Well, except for the initial capital expense of producing the turbines, installing them offshore, maintaining and replacing any faulty units, installing a supply grid to the mainland, etc.

It would be cheaper to make every homeowner buy a Honda generator and run his own household.
 
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jim hardy said:
[STRIKE]Actually last year US is #1 in world wind capacity,[/STRIKE]
oops - looks like China slipped past us, ( they have ~ 62 gw now) http://en.wikipedia.org/wiki/Wind_power_by_country

...

"I read somewhere that..." though China has a lot of turbines, a significant fraction of the total is not connected the grid, i.e. they're "bridge to nowhere" wind turbines. Even if all Chinese wind was connected, to match actual US wind generation they'd still have to significantly overbuild the US to make up for the superb wind resource advantage the US enjoys.
 
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mheslep said:
"I read somewhere that..." though China has a lot of turbines, a significant fraction of the total is not connected the grid, i.e. they're "bridge to nowhere" wind turbines. Even if all Chinese wind was connected, to match actual US wind generation they'd still have to significantly overbuild the US to make up for the superb wind resource advantage the US enjoys.

Ahh that would make sense, they could electrify small "outback" areas where there's not even a transmission system yet, without building pipelines or railroads to delive fuel.

Our wind is largely where population is sparse. Check this map -
http://www.nrel.gov/gis/images/80m_wind/awstwspd80onoffbigC3-3dpi600.jpg
Our good wind is in the middle of the country.
Note lack of offshore wind in Florida, Georgia ..

awstwspd80onoffbigC3-3dpi600_t.jpg
 
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  • #11
jim hardy said:
Ahh that would make sense, they could electrify small "outback" areas where there's not even a transmission system yet, without building pipelines or railroads to delive fuel.

Our wind is largely where population is sparse. Check this map -
...
Our good wind is in the middle of the country.
Note lack of offshore wind in Florida, Georgia ..

...
Lots of good wind *resource* offshore, but so far not a single commercial turbine installed offshore in US waters. Apparently existing offshore tower designs (e.g. european waters) are not up to the stresses of Atlantic hurricanes.
 

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