Technology

The road to 100% renewable energy

 By Robin Wylie

The world is in the midst of a renewable energy revolution…

Between 2003 and 2016, the global share of electricity generated by renewable sources grew by 24 percent. Climate change requires the world not only to continue this move towards renewables, but to accelerate the process. And while achieving this transition on a global scale will be far from easy, there are places where renewable energy generation is already significantly above the global average, showing that a fossil-free future is far from a pipe dream.

So far, the few countries that have come nearest to 100 percent renewable energy have done so largely thanks to hydroelectricity.
Paraguay, for instance, impressively generates practically all of its electricity using just two hydroelectric dams. The largest of these, the Itaipu Dam, located on the Parana river, was nominated as one of the seven wonders of the modern world by the American Society of Civil Engineers.

The Itaipu dam, Paraguay/Brazil border (Nico Kaiser, regnskove.dk)

In Europe, Norway, with its huge network of Fjords, and Albania, home to eight major rivers, both generate nearly 100 percent of their domestic electricity using hydroelectricity. Other countries are approaching 100 percent renewable energy production using a combination of hydroelectric and geothermal energy. Iceland, which generates around 70 percent of its electricity from hydro, produces an additional 25 percent using geothermal power for a combined 95 percent renewable electricity generation. In addition to power generation, Iceland also uses its geothermal resources to supply 87 percent of its heating and hot water needs. Using the same approach as Iceland, Costa Rica, with its copious tropical rainfall and numerous volcanoes, is pushing even closer to 100 percent renewable power generation. Costa Rica’s energy mix of 74 percent hydro, 15 percent geothermal, and smaller amounts of other renewables, allows the Central American nation to consistently generate upwards of 95 percent of its electricity without the use of hydrocarbons. Costa Rica even managed the impressive feat of 100 percent renewable power generation for 271 days in 2016, thanks to unusually heavy rains.

Geothermal power has also helped Kenya to massively boost its renewable power generation capacity. In the last decade, the African nation, which lies along the colossal East African volcanic rift zone, has invested heavily in tapping its geothermal potential. Starting from virtually no geothermal presence in 2007, Kenya now obtains around 50 percent of its domestically produced electricity this way. What’s more, the country plans to double its geothermal capacity within the next six years, which could help bring electricity to the 45 percent of Kenyans that still lack access to electricity. Hydropower and geothermal may have allowed a few countries to produce the majority of their electricity without fossil fuels, however, most parts of the world do not have a sufficient concentration of water power or geothermal heat to use this approach on the road to 100 percent.

Sunshine and wind, however, are a universal commodity. This, along with falling unit costs for solar panels and wind turbines, is making solar PV and wind energy the technologies of choice for new renewable development in the 21st century. Wind and solar power are at a relatively early stage of development compared to older renewable technologies such as hydro, however there are numerous success stories to suggest that, with continued growth, these technologies could soon bring more countries closer to 100 percent renewable power generation. When it comes to wind power, Denmark is currently setting the bar for the world. The Scandinavian nation, which was an early adopter of the technology, has more than doubled its installed wind capacity since 2009, and now produces an average of around 45 percent of its electricity production from its fleet of wind turbines—although on particularly windy days this figure can already exceed 100 percent. The Danish government aims to produce 100 percent of their power by 2035.

Offshore wind farm in Middelgrunden, Denmark (Kim Hansen, Wikimedia)

Portugal and Uruguay are two other wind power success stories, obtaining around 19 percent and 17 percent of their electricity generation from wind, respectively. Uruguay is a particularly good example of the rapid impact that political initiative can have on renewable development: After receiving among the largest share of clean energy investment as a percentage of GDP, the country went from almost no wind generation capacity in 2007 to approximately 850MW in 2015—equal to more than 20 percent of the country’s total electricity generation—all without subsidies or increases in consumer costs. Solar power is yet to reach the same heights as wind—global installed solar capacity is currently around 50 percent that of wind power. Italy currently produces the highest proportion of its energy from solar, around 7.8 percent of its total power consumption. Germany, once the world leader in installed solar capacity, is not far behind with approximately 6 percent of its total power generation.

But the growth of solar power shows no signs of slowing, and in the near future, we can expect to see solar making up an increasingly large percentage of power generation around the world. The most rapidly growing markets for solar power include China, which plans to invest 2.5 trillion yuan ($368 million) in renewable energy by 2020, and Mexico, whose government says it expects to increase its installed solar capacity by 20 times, relative to 2016 levels, by 2019. And Morocco, with its ready access to the Sahara desert, is setting its sights on becoming a solar superpower, with plans to install 2GW of solar capacity by 2020, or around 14 percent of the country’s total electricity generation.

With wind and solar development on an exponential growth curve, and the cost of both technologies projected to fall even further, the near future for both technologies is looking increasingly bright. More than 50 nations have committed themselves to using 100 percent renewable energy within the next 35 years, including the 48 member states of the Climate Vulnerable Forum, with numerous others pledging to significantly increase their renewables output in line with the Paris Agreement. If these ambitious goals are to be met, the promise shown by a few pioneering nation needs to be emulated on a global scale.

SEE MORE: A new record in renewable investment by Benjamin Plackett

about the author
Robin Wylie
Freelance earth/space science journalist. Currently finishing off a PhD in volcanology at University College London.