By 2020 Vattenfall hopes to expand its share in Germany's estimated over-54GW onshore capacity.
It is aiming to install 200MW, a modest target in contrast with rival energy company EnBW's aim of 1GW onshore by 2020 — up from around 250MW at present.
In all, Vattenfall currently operates 930MW of onshore wind, of which just 13.5MW is located in Gemany.
Explaining why Vattenfall is only now looking at the German onshore wind sector, a Vattenfall spokesman told Windpower Monthly: "Vattenfall is investing in offshore and onshore wind in north west Europe and wants to show more presence in Germany.
"Hopefully there will be further cooperations with other wind project developers in Germany," he added.
ABO Wind said the agreement is complementary to its traditional close cooperation with energy cooperatives.
With onshore wind auctions beginning in Germany this year, "Vattenfall, as one of the larger energy companies, offers security", said Petra Leue-Bahns, ABO Wind's head of onshore.
Vattenfall's cooperation with ABO Wind follows similar moves by other German energy companies, such as EnBW's cooperation with wind developer WSB Neue Energien announced September 2016, and MVV Energie's acquisition of wind developers Juwi and Windwaerts in 2014.
With around 400 employees, ABO Wind plans and installs turnkey wind projects. Since 1996, it has implemented around 1.6GW of onshore capacity, mostly in Germany.