Achim Steiner: Sun is rising on a greener economy

IN JUST two years, the concept of a "green economy," with its links to sustainable development and poverty eradication, has gone from being an interesting idea to being among the top two issues at the upcoming United Nations Conference on Sustainable Development, or "Rio+20".

Many people may wonder whether the green economy is just pleasing jargon or a genuine new pathway to a low-carbon, resource-efficient, and sustainable 21st century. Is it the fundamental departure from the development models of the past that its advocates proclaim, or just another case of the emperor's new clothes?

Perhaps the answer can be found in some of the extraordinary transitions taking place in the electricity and energy sectors around the world. Many people, for example, scoff at the idea that solar power could be anything but a niche market for enthusiasts or a costly white elephant, over-hyped by environmental do-gooders. In 2002, one private equity fund estimated that annual installations of solar photovoltaic (PV) arrays might reach 1.5 gigawatts by 2010. In fact, 17.5GW was installed in 2010, up 130 per cent from 2009. And PV installations are forecast to rise further this year, by perhaps 20.5GW, taking global capacity to about 50GW - the equivalent of about 15 nuclear reactors.

All of this is happening not only in developed economies such as Germany, Spain and the United States, but also in countries such as Bangladesh, Brazil, China, India, Mexico and Morocco. Indeed, according to an estimate by IMS Market Research, more than 30 countries will be part of this solar revolution by 2015.

Some countries have moved early to embrace the energy dimension of a green economy, and have introduced public policies and incentives. Considerable manufacturing capacity has been added, which has halved costs over the past two years. PV prices are set to halve again this year.

A nuclear power plant can take ten to 15 years to build, and a coal-fired power station about five years. Mid-size solar plants of five to ten megawatts are now taking only about three months to get from the planning stage to construction. With the advent of smart grids and free-market pricing, solar PV seems well positioned to provide solutions that are quick to build and scalable.

The International Energy Agency estimates that, to achieve universal access to electricity by 2030, about $33 billion (20bn) in additional annual investments in the power sector will be needed. That sounds like a lot of money, especially in the wake of the economic and financial crisis still troubling large parts of the world. But new investment just in solar PV was about $89bn in 2010. Multi-billion-dollar investments also flowed into new wind farms, geothermal plants, and a host of other renewable-energy technologies.The green shoots of a green economy can also be seen in the growth of recycling industries in South Korea, or the way Indonesia is factoring forests into its social and economic planning.

The challenge for Rio+20 is to agree policies that can accelerate all of this.

At the UN Environment Programme's upcoming Governing Council/Global Ministerial Environment Forum in Nairobi, Kenya, we will launch a landmark contribution to this debate, with the release of A Transition to a Green Economy. The report analyses how an investment of 2 per cent of global GDP in the Green Economy could unleash economic growth and positive social outcomes, while keeping humanity's planetary footprint within sustainable boundaries.

There will always be those who smile sceptically at the notion of a Green Economy. It is time to put the numbers on the table and show how advances in solar power alone are starting to prove them wrong.

• Achim Steiner is UN under-secretary general and UN Environment Programme executive director.