Clean energy derived from renewable energy sources makes up roughly a fifth of the world's energy consumption, according to a report by the Renewable Energy Policy Network for the 21st century (REN21). The global multi-stakeholder network on renewable energy published its findings this week: The organization sees renewable energy sources on the rise - despite 2013 being a difficult year with renewables facing declining policy support and uncertainty in many European countries and the US.

DW: Which country has made the biggest strides when it comes to renewable energy?

Christine Lins: Clearly the country with most advancement in renewable energy in the last decade has been China - from basically zero renewable energy to a leading position in both annual investment and total renewable capacities installed.

But we see also that with declining costs of renewable energy, more and more developing countries and emerging economies are putting a focus on renewable energy. This year's report features annual investment for the first time also relative to the share of GDP of countries. And there we see that the ranking features several developing countries, such as Uruguay, Mauritius, Costa Rica, South Africa and Nicaragua. So despite the fact that China, the US, Japan, the United Kingdom and Germany are the countries with most investment and capacity in 2013, we see that developing countries are catching up and are putting a focus on renewable energy in their future energy mix.

China seems to have taken the lead since it invested more in renewable energy than all of Europe combined last year. Is the world's biggest CO2 emitter truly going green now?

Well, what you clearly see is that the Chinese government is fully aware of the fact that economic development has to be based on sustainable development. China is massively promoting green tech and putting a focus on renewables. China's new renewable power capacity surpassed new fossil fuel and nuclear capacity for the first time and, as you said, investment in China for the first time surpassed investment in the entire European Union. China has made its way as one of the lead manufacturing house for many renewable energy technologies.

And in 2013 we not only saw massive development in the Chinese renewable energy industry, but we also saw spectacular growth of renewable markets in China in the field of solar photovoltaic, for example. China accounted for nearly one-third of the global capacity that was added. This clearly shows that it's not only about producing the equipment but it's also about deploying it in the country itself.

In the past, developing countries have argued they needed to pursue economic growth first before they could allow themselves to worry about the environment. Now it seems the tables have turned: The report points out that renewable energy mini-grids could actually help spur development by providing people in remote areas with electricity. How big is the potential for renewables in developing countries?

It's clearly not a question of either economic development or environmental protection anymore. It is clear that in many parts of the world renewable energy provides the cheapest option of energy generation in the long run. And we see that developing countries are putting a focus on renewables - nowadays we have over 95 countries in the developing world that have renewable energy policies and targets in place. All around the world energy access and distributed renewable energy are increasing.

We also see that there are new solutions - you mentioned mini-grids, and there are communication technologies as well. We see new business and finance models emerge for rural energy markets. But there is still a lot to do to insure that we make progress towards providing energy excess for all by 2030 as outlined in the UN secretary general's initiative sustainable energy for all.

Compared to 2005, when you compiled the first Renewables Global Status Report, there were just a few countries with renewable energy policies. What has changed in the meantime?

Effectively this year's report, which also marks the 10-year anniversary of REN21, sheds a light on the decade of renewable energy growth and we have come a long way. Renewable power capacity, excluding hydropower, saw a sevenfold increase during the past decade, from 85 gigawatts in 2004, to 560 gigawatts in 2013. Costs have decreased significantly and support policies have continued to spread throughout the world. We had about 55 countries in 2004; now we have 144.

What has also changed is the perception of renewables. In the early 2000s we saw upward trends but nobody really predicted the extraordinary expansion of renewables that unfolded in the last decade. Projected levels of renewables for 2020 were already surpassed in 2010, and in general global perception of renewable has shifted. Today renewables are arriving in the mainstream. According to many surveys they are the preferred energy source of the general public in many parts of the world.

Despite continued renewable energy growth, global energy demand is also on the rise. Doesn't that essentially nullify the positive effect of more renewables?

Yes, effectively. Achieving the doubling of the share of renewables by 2030 will also depend on progress made in the field of curbing demand. That is especially important in OECD countries - places with already high consumption of energy - to not only focus on the supply side but to also look on the demand side.

Christine Lins is REN21's executive secretary and a co-author of the Renewables Global Status Report.