The offshore target compares with an operational portfolio of 1.7GW at the end of 2012.
The Danish utility-developer has also set itself a cost reduction target, intending to drive down generation costs to below EUR 100/MWh by 2020.
This would represent at least 47% less than Germany's current feed-in tariff for offshore wind generation, which is set at EUR 190/kWh.
At DKK 7.8 billion (EUR 1.0 billion), offshore wind accounted for just 9% of Dong's 2012 intergroup revenue of DKK 86.7 billion, but employed 34%, 1,951 staff, of Dong's 5,670 headcount.
Last week, Dong announced plans to sell three Polish wind farms with a combined capacity of 111MW to two of the country's utilities for EUR 240 million.
The deal, with Polish utilities Energa and PGE, also includes Dong's Polish project pipeline of 700MW. The Danish company said the sale will allow it to concentrate on developing its offshore capacity.