Reuters: The renewable energy sector will see a 21 billion euro ($29.43 billion) shortfall in debt finance by 2020, following the credit crisis and a brake on lending, a senior banker said on Monday. Investors at a renewable energy finance conference in London tried to digest the implications of a banking hiatus following Lehman Brothers’ filing for bankruptcy and Bank of America’s acquisition of Merrill Lynch. The European Union has set a target of getting one-fifth of its energy from …