So how much is 20 GW of wind energy? If we assume an average capacity factor of 25% (which is relatively conservative) - that's about in practical terms:
- 15,000 individual turbines costing around €30 billion to install
- 55 TW.hr of additional annual energy production - enough for about 13 million average EU households
- Additional annual energy sales revenue of roughly €300 million (at EU prices)
One major assumption here is that the installed capacity of turbines represents only that a turbine at a rated-power is errected at a site - and doesn't consider the commissioning, grid connection, and the actual energy production. Additionally, there is no allowance for the phasing out of older turbines (not that significant now, however will get more and more so). Anecdotal reports are that 25% of new capacity in China is still not connected to the grid due to planning problems (I will try and find a reference for that!).