Speaking at EWEA Offshore 2015 in Copehagen, Ruby said: "We need to make sure we can get reliable, affordable, secure and clear energy to businesses and citizens across the continent."
Conceding that €1 trillion will need to be invested to make such an energy union work, Ruby said: "We're in the middle of a fundamental transformation of our energy system, and we're going to need a lot of investment to fulfil that transformation."
Ruby called on the policy makers to set a carbon price signal that ensures clean energy is attractive to market investors.