The two companies’ CEOs have signed a memorandum of understanding (MoU) to form a new JV they claim would become a "top-five global player" in the offshore wind sector.
They would start with 1.5GW of offshore wind projects under construction and a development pipeline of 4GW.
By 2025, the JV partners would aim to have between 5GW and 7GW of projects in operation or construction and 5-10GW under advanced development, they stated.
They would primarily target markets in Europe, the US and "selected geographies" in Asia, "where most of the growth is expected to come from", the companies added. The target markets in Asia are as-yet unspecified, but an EDPR investor presentation highlights Japan, South Korea and India as strong offshore growth markets.
EDP and Engie aim for the JV to be self-financed and operational by the end of 2019.
António Mexia, EDP CEO said: "This agreement for wind offshore represents an important step in EDP’s renewables strategy.
"We are fully committed with the energy transition and a more sustainable future, as per the ambitious goals communicated in our strategic update.
"We are confident that this partnership will reinforce our distinctive position in renewables allowing us to accelerate our path in offshore wind, one of the key growth markets in the next decade."
EDP and Engie have worked together on several large-scale offshore wind projects in the past six years.
EDP and Engie also have stakes in the 950MW Moray East wind farm being built off the coast of Scotland, which reached financial close in December 2018, and the planned 850MW Moray West sister project.
They are also collaborating on two floating offshore wind farms: the 25MW WindFloat Atlantic project off the coast of Portugal, due online later this year, and the 24MW Golfe du Lion project off the coast of France, expected online in 2020. The two companies are also bidding for France's 750MW Dunkirk project.
Isabelle Kocher, Engie CEO, said: ""The offshore wind sector is set to grow very significantly by 2030. The creation of this JV will enable us to seize market opportunities while increasing our competitiveness on one of our key growth drivers, renewables."
EDP, through its EDPR Offshore North America subsidiary, is developing several US projects.
These include the planned 1.5GW Mayflower Wind project off the coast of Massachusetts, which it is developing with oil and gas major Shell, and the 100-150MW Humboldt project off the coast of California, being developed with Principle Power and the Redwood Coast Energy Authority.
EDPR also fully owns a 400MW project off the coast of Poland.