Climate change could boost solar power production in Sweden by 5%

Swedish researchers have studied the potential effects of climate change on the country’s solar energy production potential throughout the 21st century. Aiming to establish more accurate projections of photovoltaic production in high-latitude regions, the study takes into account factors such as panel orientation, temperature, and snow cover, which are often overlooked in conventional assessments of photovoltaic potential, potentially leading to inaccurate estimates in cold climates.

“We found that the combined effects of air temperature and snowfall are as critical as solar radiation for photovoltaic production in high-latitude regions,” explained Wujun Wang, the study’s corresponding author, to pv magazine. “This situation differs significantly from what is observed in low- and mid-latitude regions. In Sweden, climate change will lead to an approximately 5% increase in photovoltaic production, meaning that global warming could have a positive effect on this output.”

Four cities studied

Researchers assessed photovoltaic production from 1951 to 2100 in four Swedish cities: Malmö in the south; Gothenburg on the west coast; Stockholm on the east coast; and Kiruna in the far north. Malmö recorded the highest temperatures and solar radiation levels, as well as the lowest snowfall. In contrast, Kiruna exhibited the coldest conditions, the lowest solar radiation levels, and snowfall approximately twice as high. Stockholm and Gothenburg represented intermediate climatic conditions. The team combined an hourly model linking snow and photovoltaics with climate projections from the regional climate model HCLIM43-ALADIN, which has a spatial resolution of 12.5 km.

The findings are presented in the study titled “Impact of climate change on photovoltaic production potential in Sweden during the 21st century,” published in the scientific journal Communications Earth & Environment.

Two climate scenarios to estimate solar power generation in Sweden

Researchers examined two climate scenarios: a low-emission scenario based on ambitious climate action (SSP1-2.6), and a high-emission scenario corresponding to limited climate action (SSP3-7.0).

The model calculated direct, diffuse, and reflected solar radiation reaching the modules, accounting for losses due to the angle of incidence and snow. It also estimated photovoltaic cell temperatures based on ambient temperature, solar irradiance, and the nominal operating temperature of the cells. Electricity production was then calculated using module efficiency and temperature coefficients.

For south-facing modules, the researchers tested tilt angles ranging from 0° to 90° in 0.1° increments. They compared the projected yields against a historical reference covering the period 1951–2014, using a reference tilt angle of 15°.

“The projected trends depend on both location and scenario, the researchers noted. Under the SSP1-2.6 scenario, annual production increases by 1.52 to 2.60 kWh/kW per decade, which is less than 0.5% per decade. Under the SSP3-7.0 scenario, photovoltaic production increases in Stockholm and Kiruna, but decreases in Gothenburg and Malmö. Despite these changes, the net variation remains limited to approximately 30 kWh/kW by 2100.”

Variability in production that could decrease in the south

Compared to the historical period, the annual variability of photovoltaic production is expected to decrease in the three southern cities studied, but increase in Kiruna. The frequency and duration of consecutive periods with no production should also decrease overall, which could reduce energy storage requirements. “In the future, an installation tilt of approximately 35° will be suitable for all the cities studied and will increase annual production by about 3 to 6% compared to the angle currently used in commercial installations,” the researchers specified.

These results highlight the importance of adapting the design of photovoltaic installations to local climatic conditions. The panel tilt angle, temperatures, and snow accumulation can indeed significantly affect system performance, particularly in Nordic regions.

“These results provide valuable insights into the photovoltaic potential in the context of climate change, the researchers concluded. They serve as a powerful tool for a wide range of stakeholders, including researchers, policymakers, photovoltaic plant owners, grid operators, investors, and engineers. They enable these parties to estimate the local effects of climate change on photovoltaic production, particularly in cold, high-latitude regions with long snow cover periods.”