The Nysted wind farms consist of "Rødsand I" (166 MW total -erected 2003) and "Rødsand II" (215 mW total - under construction). Rødsand I and II are approx 3 km (or 2 miles) from each other and estimates are that "Rødsand II" will reduce the power procution from "Rødsand I" up to 30% (depending on wind direction). As these windfarm have different owners this has caused some discussion about compensation. Experts within the field estimates that there will be a windshadow more than 20 km away from a large windfarm.
I could link to some additionals sources for information, but the ones I know are in danish.
A personal experience: I have sometimes sailed approx 5-10 km from Rødsand I, and I feel the wind is more gusty than before 2003.
"Your" windfarm is smaller than Rødsand I - but I still think there will be a difference.