Part ownership of a Ripple Wind Turbine, fancy it?

[nowty]

Can someone explain (in simple terms please) the significance of blade angle?
I could be very wrong, but I'm guessing it's all relative to windspeed so about zero means full exploitation, and bigger blade angles in higher winds are "spilling the wind" - in a sailing ship analogy - to avoid over-driving the generator?

Higher blade angle more drag. Slows it down. Think plane flaps.

... so deliberately not generating as much as it could, i.e. as much as the wind through the swept area "contains"? To not over-drive the generator and downstream electrical stuff?

Its complicated,
https://www.sciencedirect.com/science/a ... 861500155X

But the conclusion is,

For a given wind velocity, there is an optimum pitch angle where the power generated by the turbine is maximum. This optimum angle depends on the wind velocity. It is found to be 5° for Vin = 7 m/s, ϕ ~ 20° for Vin = 15.1 m/s and ϕ ~ 30° for Vin = 25.1 m/s. Operating the turbine at other angles would result in lower power. At angles deviated from the optimum angle, the performance of the turbine would deteriorate and eventually shut off. It has been seen that at these pitch angles, the angle of attack is close to the stall angle and thus experiences highest lift to drag force ratio.

[Joeboy]

The cumulative stats figure seems to represent the average wind speed quite well?

A great day indeed and not over yet.

[nowty]

Down to 9 RPM but the tips are still doing over a ton, we'll be back to a 170 mph cruise later on.

Rotor Tip Speed

[Joeboy]

Down to 9 RPM but the tips are still doing over a ton, we'll be back to a 170 mph cruise later on.

Rotor Tip Speed

RTS added to the GF acronym library?

[nowty]

Interesting, I note the benchmarking 228 MW windfarm next to GF has been subject to curtailment at times during the past 24 hours.

Whereas GF is too small to be affected and was still banging it out in the small hours.

[Joeboy]

Interesting, I note the benchmarking 228 MW windfarm next to GF has been subject to curtailment at times during the past 24 hours.

Whereas GF is too small to be affected and was still banging it out in the small hours.

With luck Kirkhill will be energised for the tail end of Xmas lights in Glasgow? That should stave off curtailment. Its a sad thing to think of but them's the reality I suppose. Pretty sure GF is written with no curtailment in the contract?

[nowty]

Ripple had said in the past that GF was too small to be constrained but could if there were local grid works going on. We have had two such outages of short intervals since energisation.

There was also a windy bank holiday time, probably around Covid times when the national grid did invoke some emergency powers which would allow them to ask non constrained generators to shut down, but in the end they were not needed.

With KH though, I'm not sure what the deal is, there was something in the CoOp minutes a while back about BEGA vs BELLA connection agreements and the latest minutes seem to suggest we are going for a BEGA connection. I've read the doc but still cannot work out what it means in practice.
https://www.nationalgrideso.com/documen ... 6/download

[Mr Gus]

For those wondering to what the heck Nowty is referring..
https://www.nationalgrideso.com/industr ... sary-terms

BEGA (Bilateral Embedded Generation Agreement)
A BEGA sets out requirements under the Grid Code, Connection and Use of System (CUSC) and Balancing and Settlement Code (BSC).

A BEGA will also provide you with Transmission Entry Capacity (TEC) and the right to operate in the electricity balancing market and export onto the NETS.

BELLA (Bilateral Embedded License exemptible Large power station Agreement)
This is a generator agreement in relation to an embedded connection to one of the Distribution networks in Scotland. The connection must be over a certain size in order to be eligible (10MW Northern Scotland or 30MW Southern Scotland). The agreement sets out requirements under relevant codes.

Flow (ish) chart
https://www.nationalgrideso.com/document/37461/download

[Joeboy]

For those wondering to what the heck Nowty is referring..
https://www.nationalgrideso.com/industr ... sary-terms

BEGA (Bilateral Embedded Generation Agreement)
A BEGA sets out requirements under the Grid Code, Connection and Use of System (CUSC) and Balancing and Settlement Code (BSC).

A BEGA will also provide you with Transmission Entry Capacity (TEC) and the right to operate in the electricity balancing market and export onto the NETS.

BELLA (Bilateral Embedded License exemptible Large power station Agreement)
This is a generator agreement in relation to an embedded connection to one of the Distribution networks in Scotland. The connection must be over a certain size in order to be eligible (10MW Northern Scotland or 30MW Southern Scotland). The agreement sets out requirements under relevant codes.

Flow (ish) chart
https://www.nationalgrideso.com/document/37461/download

It will come down to 'they'll decide'. I am entirely copaceptic (a properly excellent yet nearly worthless word) on the upcoming series of KH scenarios. Just glad to be in it.

[nowty]

GF has just beaten Dec 22, and Oct 22 should go tomorrow, I no longer think its touch and go.