Solar and wind have become attractive renewable energy sources in the battle against climate change. From 2010 to 2020, global solar capacity increased from 19.41 terawatts per hour (TWh) to 844.39 TWh. Several countries, including the United States, Spain, Morocco, China, and Turkey, source at least 1 percent of their total energy from solar. The following are the four leading countries in solar energy capacity.

1.    China

China, which intends to be carbon neutral by 2060, is the global leader in solar energy with 253 GW of PV capacity as of 2020. It added 30.1 GW to its grid in 2019 and an additional 48 GW in 2020 and is expected to accelerate solar activity in the coming years. The country intends to exceed 80 GW of annual growth in solar power and have at least 1,200 GW of combined solar and wind capacity installed by 2030.

China's largest solar project is the Huanghe Hydropower Hainan Solar Park (2.2 GW). In addition to massive solar farms, most of which are in Northern China, the country's National Energy Administration recently introduced a rooftop solar initiative to boost distributed solar power generation.

2.    United States

As of September 2021, the US had 108.7 GW of installed solar capacity, enough to power nearly 19 million homes. The country only had 76 GW of capacity in 2019. Installations are expected to continue at a rapid pace, with solar capacity forecast to exceed 400 GW by 2030. The Solar Energy Industries Association also noted the country could break annual installation records in each of the next three years while the investment tax credit is still active.

Despite these projections, there are some concerns. According to Wood Mackenzie, solar prices increased year-over-year across all market segments in Q2 2021 due in large part to COVID-19-related supply chain constraints. This marked the first time prices increased since the company began tracking data in 2014.

3.    Japan

Japan had 71.7 GW of installed solar capacity at the end of 2020. Despite this already exceeding the country's goal for 2030, the Ministry of Environment proposed in July 2021 that Japan expand this target to 108 GW. Without any change in policy, Japan would reach 88 GW of PV capacity by 2030. Much of the increase would come from rooftop installations on government buildings. 

4.    Germany

As the solar energy leader in Europe, Germany had 55.3 GW of installed capacity as of June 2021 and intends to reach 100 GW by 2030, at which point it would source 65 percent of its energy requirements from renewable sources. The country operates a feed-in tariff scheme to promote private installations. Germany’s largest solar project is the 187 MW Weesow-Wilmersdorf facility near Berlin.