Plus they are a highly complex shape, it would be tough to make them, and make sure they are all the same. Interesting work is being done vertical wind turbines, which would be a heap easier to make.
tygertung,
May 4, 3:01am
Aircraft wings are also a highly complex shape, and also even composite aircraft wings get regular inspections.
He obviously didn't do the maths! Not sure why he thinks he is entitled to a large buy back tariff, all it means is that consumers without solar are subsiding his installation. We have 5kW system and in our case are paid 8c per unit if we have any excess. We hope to be able to use all our generation for household appliances and our EV. Our payback period will be 4 to 5 years, 15% to 18% ROI, better than any bank.
skiff1,
May 4, 3:41am
unlike the average aircraft wing, which is widely acknowledged as no more complex than a rock.
apollo11,
May 4, 3:55am
A wind turbine blade would be even tougher to build than an aircraft wing. You could do it, but it would be expensive.
tygertung,
May 4, 4:17am
It would be pretty easy to make them all the same, they have to do this on aircraft for over 100 years. You don't want two different wings.
You make the frames up and use jigs to build them.
Have you not worked on aircraft before? I am an aircraft engineer by trade so am familiar with the concepts. Similar concepts go into building boats.
The main issue is that of stress, not construction to tolerance.
Wing design and construction is a mature field in aeronautics.
tony9,
May 4, 4:30am
We cannot. The three coal units at Huntley are running close to full load 24/7 at the moment. There are no more coal fired stations available.
Maybe burn more gas - bugger, we are running out now.
We can burn diesel/ATK in some plants, maybe another 250MW (same as 1 unit at Huntley)
Fonterra and others are proud of the fact that they have switched from coal to electricity - do you see the problem?
Bottom line, right now NZ is close to max capacity for power generation and the storage levels are falling in the major storage lakes. Fingers are crossed.
marte,
May 4, 5:05am
Burn plastic waste, 2 problems solved at once.
apollo11,
May 4, 5:06am
I'm a design engineer (retired) with twenty-odd years experience designing for manufacture. For small stuff, you could probably use an extrusion, such as yacht masts are made. For the big stuff, and some of it dwarfs a 747 wing, you'd need to simplify the form. Otherwise every airfoil section would be slightly different shape and sitting on a rotated axis. They are more like a giant prop blade than a wing in form. If you simplify the form, you might lose efficiency. As per aircraft, it would need to be glued or riveted together. The people who make these things have probably tried aluminium and it has been found wanting. However for vertical wind turbines aluminium might be ideal.
Was looking at that as well, But the Providers that took the excess raised the rates to sell in winter, and dropped the price they paid for the power going back to the grid, Also only paid for so much per day. Found that with our wetback, we would only save $38 a year if we went with the panels.
tony9,
May 4, 8:55pm
Maybe, in certain places.
They used computer simulations, only, not real life experience. And gave UP TO 15%, where conventional turbine were in rows where the back rows had a loss in efficiency. That would possibly valid in off shore farms, but here we usually see a single row on top of a ridge.
So far conventional turbines easily out perform vertical ones. But if the blades had variable angle of attacks so that the one coming into the wind had less drag then they might be viable. But that would add to complexity and maintenance.
apollo11,
May 4, 9:11pm
You really need to shield the leeward side, otherwise they see little extra increase in generation from an increase in wind speed. Or have a pair, contra-rotating, with a funnel between the two. The advantage in having your generating gear close to ground level is a huge plus for maintenance.
philltauranga,
May 4, 9:25pm
Do those vertical blades have any type of adjustable pitch connected to a wind direction gauge so the flat side of a blade can face the wind and the narrow side return into the wind?
apollo11,
May 4, 10:36pm
I think they are just fixed blades. Anything that pivots is likely to self destruct when the wind picks up. Of course and funneling system would need to be able to move to face the wind, unless the wind is from a uniform direction, so my idea is probably not so good.
philltauranga,
May 4, 10:53pm
Well I assumed they would have to have adjustable pitch just to work properly so had a googly and a guy in Japan has made one which uses vertical rotating cylinders instead of blades, it uses the "magnus effect" instead of adjustable pitch and can stand a typhoon, pretty cool.
Cut paste this: Magnus Opus: Challenergy Eyes Clean Power With Its New Type of Wind Turbine
philltauranga,
May 4, 11:27pm
Correction: I should say there is still a blade there, but it has a rotating cylinder in front of it, not instead the blade.
naturally all the diesel used in manufacturing and installing then turbines will come from fish and chip shop waste cooking oils. wake up people wind turbines are NOT cost effective.
tygertung,
May 5, 1:25am
Well why are there so many of them in Germany? When I was in Northern Germany there were loads.
apollo11,
May 5, 1:27am
Public subsidies.
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