Energy question of the week: Is any country already able to meet all of its energy needs from renewable sources?

A growing volume of energy originating from renewable sources is being used right around the world – from Europe to America to China. This trend is especially widespread in the electricity-generation sector. Over the last couple of years, the USA and the countries of the EU have been building more power station capacity based on wind, water and solar energy than they in conventionally fuelled power stations, – that is, coal, gas or uranium. However, is any country already able to meet all of its energy needs from renewable sources?

Despite the positive trend in the power generation business, not a single nation on Earth has been able to dispense with fossil fuel to meet its energy needs at this time. The primary reason for this is the mobility provided by internal combustion engines, which are powered primarily by fuels derived from crude oil. However, in 2009, the EU did manage to meet one fifth of its electricity needs from water, wind and solar power. Austria tops this board, producing about 70 percent of its electricity climate-neutrally from hydroelectric power stations. Finland shares second place with Portugal, each at 30 percent. "Outside the EU, Norway stands out, since it sources almost all of its electricity from hydroelectric power," says Franz Trieb from the DLR Institute of Technical Thermodynamics in Stuttgart, where he is responsible for the area of Systems Analysis and Technology Assessment.

Hydroelectric power currently provides the largest amounts of electricity from renewable sources

On other continents, it is once again hydroelectric power stations, some of enormous size, that offer a way of becoming independent of coal and nuclear power. Brazil sources 85 percent of its electricity from hydroelectric power stations, with Chile obtaining just over half and Argentina still managing a robust 35 percent (2008 figures, REN21 Global Status Report). Costa Rica uses fossil fuels in the generation of only five percent of its electricity needs, while Mozambique and Zimbabwe actually manage to generate 99 percent of their electricity from renewable sources. "Of course, small countries with small populations have it easier" says Trieb.

The dam at the Ottenstein power plant and the reservoir behind it. Credit: EVN-AG. Top image: Waterfall on the River Leine. Credit: Daniel Schwen.

"Before the industrial revolution, there was not a single country that did not source its entire energy needs from renewable sources," states the DLR energy expert. And this is precisely the objective towards which we should strive again, right around the globe. In 2009, China installed 13.8 gigawatts of new wind-operated power generating capacity, actually overtaking the USA, Germany and Spain in the process. However, due to the rising demand for electricity, China also built several times that capacity in the form of new coal-fired power stations. Viewed globally, over the last two years, the newly-constructed power stations fuelled from renewable sources account for 47 percent of all new installed capacity, virtually matching that of new generating plants built to run on fossil fuels (53 percent).

Mobility based predominantly on crude oil

With the proposed feed-in tariffs, new technologies – especially in the solar power sector – and binding limits on carbon dioxide emissions, this trend is going to intensify in the years to come. However, despite all this progress, most automotive fuels remain dependent on crude oil, and demand for them is rising as the number of vehicles in China and India continue to grow. The worldwide volume of biofuels produced in 2009 rose to 76 billion litres of bioethanol and 17 billion litres of biodiesel. However, land available for agriculture is limited, and is needed for the production of food. This is why no further significant levels of growth can be anticipated here. Before electric drive systems start to limit the dominant role of the internal combustion engine, it is important to take steps to further improve the efficiency of motor vehicles.

The DLR Energy question of the week in 'The future of energy' Year of Science

The Federal Ministry of Education and Research (BMBF) has given the Year of Science 2010 the motto 'The future of energy'. For this reason the science journalist Jan Oliver Löfken will this year answer a question on the subject of energy in his blog each week. Do you have a question about how our energy supply might look in the future? Or do you want to know, for example, how a wave power plant works and how it can efficiently generate electricity? Then send us your question by email. Science journalist Jan Oliver Löfken will investigate the answers and publish them each week in this blog.