Wind turbine brake control

[Gareth J]

Yes, hydro has a great power profile, even if only available in winter, complements cheap PV well. I've looked into it here as we have a small stream. But it's not that steep and penstock works are a massive investment. Also, don't even think of mentioning it to the EA!

Wind is pretty good, if on grid, with excess generation dumped into a night storage heater or two, the house is at its toastiest when it's blowing a hoolie. Which is exactly when it's hardest to keep heat in the place.

 

[Erie Fred]

Yes, hydro has a great power profile, even if only available in winter, complements cheap PV well. I've looked into it here as we have a small stream. But it's not that steep and penstock works are a massive investment. Also, don't even think of mentioning it to the EA!

Can't you get Greta to help ?

 

[gaz1]

I think most people put more value on kWh of electricity than a cattle trough of water drawn out from underground. Well designed wind turbines are optimised to do this. Well designed wind pumps are optimised to do that.

Lets be honest here all they have done is redesigned an old tech and called it new with a high price tag to go with it

by that i mean the old windmill/corn mill/smock windmill

and its still based on if the wind gets too high shut it down

 

[Brad93]

Is it very exposed there?
There are better resources but as a rough guide,

Where are the windiest parts of the UK?

The windest places in the UK have been recorded at the top of mountains, usually in the west of the country.

www.metoffice.gov.uk

With a low mean annual average average theres just not a lot of wind to collect.

As a sensible proxy, if you can see loads of commercial turbines from there, you're probably in a decent site.

I mean there's 18 acres of open field behind then a bit of a valley.

 

[Brad93]

Is it very exposed there?
There are better resources but as a rough guide,

Where are the windiest parts of the UK?

The windest places in the UK have been recorded at the top of mountains, usually in the west of the country.

www.metoffice.gov.uk

With a low mean annual average average theres just not a lot of wind to collect.

As a sensible proxy, if you can see loads of commercial turbines from there, you're probably in a decent site.

Mean 8-10 knots according to that map on net office.

 

[minimutly]

Yes, hydro has a great power profile, even if only available in winter, complements cheap PV well. I've looked into it here as we have a small stream. But it's not that steep and penstock works are a massive investment. Also, don't even think of mentioning it to the EA!

Wind is pretty good, if on grid, with excess generation dumped into a night storage heater or two, the house is at its toastiest when it's blowing a hoolie. Which is exactly when it's hardest to keep heat in the place.

The maths is v simple - head in metres, times flow in litres a second, times 9.81 (gravity), times an efficiency factor (0 to 1) gives you power in Watts.
So 10 litres a second at 100metres head gives you 7.8kW, assuming 0.8 overall efficiency.
So if you think you have 10 litres a second the stream won't miss, and you can afford 150m or so of pipeline that can carry 10 litres a second, you need to work out the diameter of pipeline that gives you a max velocity of 5metres a second or thereabouts, and can withstand two or three times 100m...
I've looked at a few sites for people who thought they had potential, but when you apply the maths, it all dissapears.

 

[Gareth J]

The maths is v simple - head in metres, times flow in litres a second, times 9.81 (gravity), times an efficiency factor (0 to 1) gives you power in Watts.
So 10 litres a second at 100metres head gives you 7.8kW, assuming 0.8 overall efficiency.
So if you think you have 10 litres a second the stream won't miss, and you can afford 150m or so of pipeline that can carry 10 litres a second, you need to work out the diameter of pipeline that gives you a max velocity of 5metres a second or thereabouts, and can withstand two or three times 100m...
I've looked at a few sites for people who thought they had potential, but when you apply the maths, it all dissapears.

Indeed, the maths wasn't great when I looked into it. Not nothing but the ground just isn't steep enough to get a useful head without ££ cable/pipe lengths.

 

[Gareth J]

Mean 8-10 knots according to that map on net office.

Have a look at a few existing turbines and see where the windspeeds you might get sit on their performance charts. Something like this gives a bit more data.

Ren SMARTWind Report

www.rensmart.com

 

[Gareth J]

Lets be honest here all they have done is redesigned an old tech and called it new with a high price tag to go with it

by that i mean the old windmill/corn mill/smock windmill

and its still based on if the wind gets too high shut it down

Yeah, sure. Kind of. In the same way that everything newer builds on information from the past. But also, no, most small scale WTs have insanely high cut out speeds. Once wind is too high for maximum generation, they are modulated to reduce efficiency, rather than shut down. One mechanism has been alluded to already here. And improvements in design have improved efficiency. A 1910 design still runs... ok. There are plenty of model T fords running too, does that make them the optimum vehicle for the school run?

 

[gaz1]

I mean there's 18 acres of open field behind then a bit of a valley.

can you build another workshop building ?

as id have that fitted with solar and then fit wind inside of it as a 4 way wind access to

ive noticed on some high rises that they have both solar and wind turbines on them the solar panels being above the wind turbines

 

[Brad93]

can you build another workshop building ?

as id have that fitted with solar and then fit wind inside of it as a 4 way wind access to

ive noticed on some high rises that they have both solar and wind turbines on them the solar panels being above the wind turbines

No it's grazing / agricultural land only

 

[Islander71]

I think the highest windspeed we;ve had since the wind turbine has been up was a 90mph storm. The turbine continued running at full power until the grid power lines went down, power cut, when the invertors automatically shut down the power produced, though the turbine continued turning with the blades feathering out. One point I would make is that I wouldn't site one less than 100yds of a dwelling because of noise.
The Iskra is an upwind turbine and not too noisy more a swishing sound and with the generator hum. A Proven downwind turbine put up by the lobal council in an act of virtue signalling insanity next to the local primary school can sound like a diesel cement mixer thudding away due to the blades being in wind shadow each time they pass the tower. Incidentally the first time it disintegrated. one of the blades flew clean over the playground and buried itself into the schoolhouse garden! The early Proven blades were made from double skin plywood with internal ribs. It was re-fitted with plastic blades, but after a furling spring broke it eventually after running completely un-balanced with the one blade flapping about, disintegrated again. It has just been refitted with a completely new hub, after standing as a bare pole for a year or two.

My Iskra suffered main bearing wear after about 10 years which caused quite a lot of damage to the rotor magnets and to the stator needing a comprehensive rebuild back at the factory, which had by then become Evance. So they do need a fair bit of servicing and renewal of parts. By comparison the solar panels dont require any attention.

 

[Gareth J]

My Iskra suffered main bearing wear after about 10 years which caused quite a lot of damage to the rotor magnets and to the stator needing a comprehensive rebuild back at the factory, which had by then become Evance. So they do need a fair bit of servicing and renewal of parts. By comparison the solar panels dont require any attention.

Can ask about your experience with this? I'm a bit paranoid my main bearing is getting tired but not sure about diagnosis. Maybe PM is more appropriate than furthermore cluttering up your thread!