Iceland Leads Global Rankings For Cleanest Power Grids, Norway And Sweden Follow—Report

A recent March 2026 study by Energy World Mag has highlighted how different countries are progressing toward cleaner and more resilient power systems. The report evaluated 76 nations using a Clean Energy Sustainability Index (CESI), which measures how environmentally friendly, efficient, and reliable their electricity grids are.

According to the findings, Iceland has the lowest carbon footprint in electricity generation worldwide. Its grid records a carbon intensity of just 28 gCO₂ per kilowatt-hour, meaning it produces the least harmful emissions among all countries studied. A large share of Iceland’s electricity comes from renewable sources, accounting for 82.4% of total energy consumption, while only 10.3% depends on fossil fuels. The country’s strong reliance on geothermal and hydroelectric power plays a major role in maintaining this low-carbon system.

Norway ranks second in the study, supported by its heavy use of hydropower. Around 89.1% of its electricity comes from hydroelectric sources, making its grid highly sustainable. Renewable energy accounts for 61.4% of its overall energy use, and the country also shows strong energy efficiency, requiring only about 1.1 kWh to generate one dollar of GDP.

Sweden follows closely, with a balanced and diverse energy mix. Only 24.9% of its electricity comes from fossil fuels, while renewable sources contribute a major share. Hydropower alone accounts for about 40% of Sweden’s electricity production. The country also maintains low emissions, with carbon intensity at around 34.8 gCO₂ per kilowatt-hour.

Switzerland stands out for its exceptional energy efficiency. It requires just 0.51 kWh of energy to produce one dollar of GDP, the lowest among all countries in the top ten. Switzerland also uses a mix of energy sources, including hydroelectric power, which contributes 55.9% of electricity generation, along with fossil fuels and other alternatives.

France ranks fifth, with a relatively low carbon intensity of 40.8 gCO₂ per kilowatt-hour. A significant portion of its electricity comes from alternative and nuclear energy sources, accounting for 46.7% of total energy use. France also maintains efficient energy use, requiring only 0.86 kWh per dollar of GDP.

Other countries in the top ten include Finland, New Zealand, Brazil, Denmark, and Slovenia. These nations show varying strengths in renewable energy use, hydropower generation, and energy efficiency, although their carbon intensity levels are higher compared to the top-ranked countries.

The study considered several factors, including carbon emissions from electricity production, energy consumption relative to economic output, the share of renewable and nuclear energy, and dependence on fossil fuels. Together, these indicators help measure how sustainable and future-ready a country’s energy system is.

An important observation from the report is that geography plays a major role in shaping clean energy systems. Countries like Iceland and Norway benefit from natural resources such as geothermal energy and abundant water for hydropower. However, replicating such models in other regions may not be easy.

The report suggests that countries without these natural advantages will need to invest heavily in energy infrastructure, storage technologies, and diversified renewable sources to achieve similar results.