BERLIN, March 18 (Reuters) - Germany's government will discuss plans to raise the size of its renewable energy fund to 1 billion euros from a current 300 million, according to a draft paper seen by Reuters on Friday. In its effort to make up a shortfall of nuclear power due to a three month moratorium imposed this week, the government aims to boost renewable power and energy saving. It will focus on off-shore wind energy and making buildings more energy efficient. (more)