2015 was a record year for renewables. According to the Global Status Report, wind, solar and hydropower all boomed. Worldwide, 147 gigawatts (GW) of new renewable power capacity was installed. Wind power accounted for 63 GW, solar 55 GW and hydropower 16 GW.

China, the United States, Great Britain and India saw the biggest construction of new renewable power capacity. Denmark, Germany, Sweden, Spain and Portugal, meanwhile, took the lead on installed renewable capacity per capita. These European countries had already invested heavily in the sector over previous years.

Falling prices spur global investment

The annual status report is published by the Renewable Energy Policy Network for the 21st Century (REN21), a network of 700 experts from around the world, and presents a comprehensive overview of global renewable energy development, as well as political and investment trends.

Worldwide, the report found that $286 billion dollars (256 billion euros) were invested in renewable energy last year - up $13 billion on the previous year.

So what's driving the boom? REN21 executive secretary Christine Lins said falling costs of renewable power are not only good for the environment - they're also good for business.

"The report shows that renewable energy is commercially competitive - that in many countries, it can compete with the price of fossil-fueled energy," she told DW. And that's at a time when fossil fuel prices have hit a historic low, Lins added.

More renewables in the global power mix

According to the report, in 2015 renewables provided almost 24 percent of electricity globally. That's up by about 1 percentage point over the previous year.

In Europe, the share of renewables in the power mix is already at around 44 percent, Lins explained. In 2010, that figure was just 24 percent. Germany now covers over a third of electricity demand from renewable energy, as it exports renewable power to neighboring countries.

But the report also highlights the trend that emerging economies have begun to invest more in renewables than developing countries.

Picking up the pace to meet climate targets

Still, while the share of renewables in the power mix saw a significant rise, the share of renewables in overall energy use - including heating, industry and transport - is less impressive. By the end of 2015, renewables accounted for 19.2 percent of global energy use - up just 0.2 percent on the previous year.

That's mainly because of sluggish development in the transport and heating sectors, said Lins. "There, much more has to happen," she said.

The share of renewables in road transport lags at just 4 percent, and at 8 percent in heating for buildings and industry.

To meet the Paris climate target of keeping global warming below 2 degrees, the world needs to give up fossil fuels completely by the middle of this century, Lins pointed out. "Here, we're still not on the right track," she said.

Still, she sees opportunities to reach the target: "The expansion of renewables must increase by a factor of ten - which is possible." A look at how quickly photovoltaic solar has developed over recent years reflects this. "This shows how innovation and falling prices can dramatically accelerate things."

But to reach the Paris climate target, Lins said stronger political support is needed.

Lins says more must be done to counter the misconception that renewables are more expensive than conventional energy sources

Reducing subsidies could help, Lins said. "Until now, we have spent four times more money on subsidizing fossil-fueled energy than supporting renewable energy."

The smooth operation of a 100-percent renewable electricity supply is possible - as Portugal has recently shown. "For four days, renewable energy generation took over completely," Lins said. In Denmark too, renewables have frequently covered the country's entire power demand.