Write a summary of the article Switching to Renewables.

The global energy crisis is a daunting challenge. Yet we do not have to look far for the solutions. Energy derived from the sun, the wind, the Earth's heat, water and the sea has the potential to meet the world's electricity needs many times over, even allowing for fluctuations in supply and demand. We can greatly reduce the amount of energy we use through simple measures like insulating buildings, recycling materials and installing efficient biomass stoves. Biomass from waste, crops and forest resources has potential to provide a renewable source of energy-although this raises significant social and environmental issues....

Around the world, people are taking steps in the right direction. In 2009, China added 37 GW [gigawatts] of renewable energy, bringing its total renewable capacity to 226 GW-equivalent to four times the capacity required to satisfy the total peak electrical power consumption of Great Britain or over twice the total electric capacity of Africa! In Europe and the U.S., more than half of all new power capacity installed in 2009 came from renewable sources. In the developing world, more than 30 million households have their own biogas generators for cooking and lighting. Over 160 million use "improved" biomass stoves, which are more efficient and produce less greenhouse gas and other pollutants. Solar water heating is used by 70 million households around the world. Wind power capacity has grown by 70 per cent, and solar power (PV) by a massive 190 per cent in the last two years (2008 and 2009). During the same period, total investment into all renewables has increased from about $US 100 billion in 2007 to more than $US 150 billion in 2009.

But the pace of change is far too slow. Non-hydro renewables still only comprise a mere 3 per cent of all electricity consumed. Huge quantities of fossil fuels continue to be extracted and used, and global carbon emissions are still rising. Government subsidies and private investments in fossil fuels and nuclear power ventures still vastly outweigh those into renewable energy and energy efficiency, even though the latter would give a far greater long-term return. While thousands of houses throughout the world, especially in Germany and Scandinavia, have been built to "passive house" standards that require almost no energy for heating and cooling, many more construction projects follow old-fashioned, energy-inefficient designs.