How can you put a fixed & binding level on renewables ?

.... when they are by definition reliant on dynamic / organic systems - like forests, wind etc ?

EU close to renewables deal at energy summit - Yahoo! News: "BRUSSELS (Reuters) -
European Union leaders were on the brink of agreeing on Thursday to set a binding pan-European target for renewable energy sources as part of an ambitious strategy to fight climate change.


After the first working session of a two-day summit, Swedish Prime Minister Fredrik Reinfeldt said the 27 leaders had agreed in principle to set a mandatory target for renewable sources such as wind, solar and hydro-electric power, and allocate the burden among member states later.

'We have agreed that we need a target for renewable energy supply and that it will be binding, but it will follow a discussion on what that means for each member state,' Reinfeldt told reporters.

He said EU president Germany would draft a compromise including the word 'binding' to be put to leaders on Friday. Irish and Spanish ministers confirmed the breakthrough but some diplomats said a handful of countries were still opposed.

The executive
European Commission has proposed an EU-wide binding objective that 20 percent of energy consumption come from renewable fuels by 2020.

French
President Jacques Chirac told the leaders that nuclear power must also play a role in Europe's drive to cut greenhouse gas emissions, blamed for global warming.

Speaking at his last European Union summit in Brussels, the"