On June 4, 2018, the Renewable Energy Policy Network for the 21st Century (REN21) published a report covering the global state of the electric power industry. Their findings are very promising for solar power and other renewable sources, which received record-breaking investment in the year 2017.
The global investment in renewable energy for 2017 was 310 billion USD, accounting for 68.2% of the total. For comparison, investment in fossil fuels was 103 billion USD, representing 22.6%, and the remaining 9.2% corresponds to nuclear power, with 42 billion USD. In other words, the investment in renewable sources was more than twice the investment in fossil fuels and nuclear power combined!
The 310 billion USD of renewable energy investment are further divided into 45 billion USD for large-scale hydropower (over 50 MW) and 265 billion USD for solar, wind, small-scale hydro and other renewables.
The REN21 report concludes that low cost has been a key factor attracting investment in solar and wind power. Utility-scale solar arrays and wind turbines can now deliver electricity for less than 0.02 USD/kWh, which beats the electricity price of fossil fuels.
Globally, 98 GW of solar power capacity were added in 2017, and Australia was one of the eight countries adding more than 1 GW. New wind power projects add up 52 GW, and the total capacity addition in renewable sources was 178 GW. Thanks to the growth of renewables in recent years, they now generate 23% of the electricity used by the world, where 7.4% corresponds to solar and wind power. Hydropower continues to be the dominant renewable source, with 16.4% of total generation.
Although solar power and other renewables had an excellent year in 2017, the REN21 report has identified three areas that continue to represent a challenge: transportation, heating and cooling. Renewable energy is held back in these areas due to the variable output of solar and wind power, and the technological challenge of storing large amounts of electricity.
These challenges could be overcome as energy storage technologies continue to be developed. The International Renewable Energy Agency (IRENA) predicts massive cost reductions for batteries before the year 2030. There are also many thermal energy storage concepts that have already been deployed successfully in heating and cooling systems.