coastal sites and inland sites

[rameshmuthya]

Dear WASP team,

Along Gujarat Coastline winds were measured a while back. Wind farms are coming up nearly 15 km inland. How justified are we in using WASP to make AEP estimates for such inland locations? A second question that never gets a straight answer is about what is the maximum distance from the met mast we can allow for making AEP calculations. The terrain is almost plains for hundreds of kilometers.

[Ib]

Dear Rameshmuthya

Its always best to have measurements and application sites close - both in terms of setting (coastal, flat terrain, complex , etc) and distance (the WAsP "similarity principle"). However, WAsP is designed to estimate e.g. AEP at points many kilometers away from a measurement site. In this context 15km well within the "norm". The key question is whether the overall wind climate is governed by large scale forcing (in which case your two sites should experience close to the same forcing except for the terrain modification, which WAsP will take care of for you) or more dominated by very local flows (e.g. if you were in a narrow valley, then your distance of WAsP application could be very limited)...
In your case of Gujarat, with hundreds of kilometers of plains and presumably the wind climate dominated (at Wind power relevant speeds) by large scale systems (the monsoons) (?) you should be ok within several tens of kilometers.
To give a more accurate answer to your second question (as you can see very connected to the first one) one will need to do a study of Gujarat wind climatology either by studying - possibly modelling with mesoscale model -the meteorology or by looking at WAsP cross predictions between good measurement sites with reasonable length (years) good quality at different locations if they exist.

Best wishes

Ib
WAsP team