Renewables are becoming globally more competitive. And an increasing number of studies show they have an economic edge, especially if environmental and health costs are taken into account.
In Germany there is much discussion around renewable energies and cost. Fans of conventional energy sources hope to slow the rapid expansion of wind and solar power since, they say, the cost of renewable energies is too high.
The forum Green Budget Germany (FÖS) has now put forward a comprehensive study that compared all power technologies in Germany, including all known costs. Germany's energy cooperative Greenpeace Energy had commissioned the study.
Things considered were overall expenses, as well as "other effects from using conventional energies including costly consequences - for example, environmental and climate damage," said study leader Swantje Küchler from FÖS.
In the case of nuclear power, the damages after a possible nuclear accident were also taken into account. So far, the risks for large accidents worldwide have been carried by the general public, as power plant operators usually don't have the appropriate liability insurance.
Most bang for your buck
In the overall assessment, wind and solar power gave the most bang for your buck, according to calculations by FÖS. In 2014 electricity from wind and large solar power plants cost Germany between five and 10 euro cents per kilowatt-hour (kWh). In contrast, the cost of electricity from natural gas, coal or lignite power plants was distinctly higher - between 11 to 17 cents per kWh.
Particularly expensive in comparison was nuclear power. Even though no new nuclear power plants will be built in Germany, with the last reactors expected to shut down in 2022, scientists contemplated the cost of nuclear energy from fictitious new power plants. That, plus the potential harms to the environment and human health arising from accidents, raised the total cost of nuclear power to between 19 to 50 cents per kWh.
A need for transparency
Energy scientists from other institutions felt vindicated by the study.
"The results are basically consistent with our studies, which show that conventional energies are significantly more expensive than renewables," said Claudia Kemfert of the German Institute for Economic Research (DIW).
Consequently, experts are calling for honesty and transparency in the debate, in which all costs should be taken into account.
"The problem is the high costs of coal and nuclear power are hidden from customers, who pay for them indirectly. We wanted to fix this grievance," said Marcel Keiffenheim of Greenpeace Energy.
Also, the study provided good evidence to "promote the development of renewable energies as soon as possible for economic reasons."
Tackling global climate change with renewables
The International Renewable Energy Agency (IRENA) in Abu Dhabi arrived at similar results in its most recent study Renewable Power Generation Costs in 2014. They found the generation of electricity from fossil fuels took a toll on human health and climate and added up to 11 cents per kWh.
Since the cost of renewables in recent years has plunged worldwide, there is now "a historic opportunity to build a clean and sustainable energy supply and, therefore, prevent catastrophic climate change in an affordable way," according to Adnan Z. Amin, Director-General of IRENA.
At the same time, the march to renewables created "new jobs and reduced the import bills for fuels."
Above all, wind energy in many places in the world is economically competitive, often being cheaper than fossil fuels. According to an IRENA study, some windy places can already produce a kWh of power for four cents.
But the average production cost for wind power varies across regions. In China and Asia, it would cost around five or six; in North America, around six; and in Africa, around seven cents per kWh.
IRENA also saw much potential in the falling prices of solar power - particularly cheap in sunny countries. In the Middle East, operators of solar parks, or photovoltaic power stations, said they already generated electricity for five cents per kWh.
Renewables should also be helpful for the approximately 1.3 billion people who have up to now lived without electricity. According to IRENA's report, renewables in this case were the cheapest energy source, especially in comparison to diesel.
With a new online platform, the international agency hopes to strengthen the push for renewable energies, for which worldwide data are now available.