New technology and falling costs are spreading renewable energy across the globe, particularly in developing nations where investment in solar and wind energy is growing fastest.
Half of people around the globe still rely on traditional biomass for heating and cooking, and nearly as many people have no or only intermittent access to electricity. But investment in sustainable energy sources is beginning to change that.
Over the past five years, investment in renewable energy in developing countries has soared. For example, in 2007, developed countries invested 2.5 times more in renewable energy than the rest of the world. But by 2012, developing nations had pulled nearly even, spending more than $112 billion, while developed countries spent $132 billion.
Two-thirds of the 138 countries with policies to encourage renewable energy sources are in the developing world. China leads the world and continues to expand renewable energy, investing $67 billion in 2012, but other countries are showing dramatic increases, including South Africa, Morocco, Mexico, Chile and Kenya. The region where renewable energy is growing fastest is the Middle East and Africa, which increased spending by 228 percent in 2012 to $12 billion.
United Nations Secretary-General Ban Ki-moon has made sustainable energy one of his five priorities, particularly as a way to fight entrenched poverty. This Sustainable Energy for All Initiative is focused on ensuring universal access to energy, improving energy efficiency and enhancing deployment of renewable sources.
The International Energy Agency estimates that global energy demand will grow 36 percent by 2035 and that 93 percent of that new demand will be in the developing world. Because only about 40 percent of the increased electrical needs can be met by an electrical grid, renewable systems like solar thermal, photovoltaic, wind turbines and sustainable biomass likely will continue to grow in importance.