Carbon Rotec already manufactures the NR58.5 blade for Nordex's low-wind N117/2400 when demand outstrips the turbine manufacturer's own production capacity.
It will now manufacture the NR50 blades for the N100 2.5MW and 3.3MW turbines, and NR65.5 blades for the N131 3MW turbines when Nordex's facilities cannot meet demand.
Nordex said that the extension of the deal was necessary in order for the company to be able to "react flexibly to any increases in demand".
To deal with an increase in demand, particularly for longer-bladed turbines, Nordex is also investing EUR 50 million to expand its own main blade factory in Rostock in Mecklenburg-Vorpommern, northern Germany.
The manufacturer received its first order for the N131 in September, after it was launched in late 2013.