As the fastest growing sector and accounting for around a fifth of worldwide electricity production, renewable energy has emerged as a significant source in the global mix. Much of this success has stemmed from significant policy effort and economic incentives at the country level, particularly in the OECD. Massive investment has taken place on a global scale, with costs for most technologies falling steadily. As a result, renewable energy technologies are becoming more economically attractive in an increasing range of countries and circumstances, with China, India and Brazil emerging as major