Switzerland gets most of its electricity from hydropower and nuclear energy, which together account for roughly 90% of domestic production. But electricity is only part of the picture. The country still relies heavily on imported oil and natural gas for heating, transport, and industry, making its total energy mix far more fossil-fuel dependent than its clean electricity grid might suggest.
Hydropower: The Backbone of Swiss Electricity
Hydropower supplies about 61.5% of Switzerland’s electricity, making it by far the dominant source. The country operates 704 hydroelectric plants with a combined capacity of nearly 16.6 gigawatts, producing around 37,350 gigawatt-hours per year. Switzerland’s mountainous terrain and abundant water give it one of the highest concentrations of hydropower infrastructure in Europe.
These plants fall into two broad categories. Run-of-river plants sit along rivers and generate electricity continuously as water flows through them, contributing about 18,087 GWh annually. Storage and pumped-storage plants use reservoirs high in the Alps to hold water and release it on demand, producing a combined 19,262 GWh per year. This split matters because the storage plants act like giant batteries: they can ramp up production during peak demand or in winter when river flows drop, giving Switzerland unusual flexibility in managing its grid.
Nuclear Power and Its Uncertain Future
Nuclear energy provides roughly 28.5% of Swiss electricity. Three operating sites remain: Beznau (which houses two reactors), Gösgen, and Leibstadt, with a combined output of about 2,800 megawatts. A fourth site, Mühleberg, shut down permanently in December 2019 for economic reasons. Its spent fuel was fully removed by 2024, and final decommissioning is expected to wrap up by 2029.
Switzerland voted in 2017 to ban the construction of new nuclear plants. However, the existing reactors have no fixed retirement dates. They can continue operating as long as the Federal Nuclear Safety Inspectorate certifies them as safe, and there are currently no plans to decommission any of the remaining three sites. This means nuclear will stay in the mix for years, but its share will inevitably decline as aging reactors eventually go offline.
Oil and Gas: The Hidden Bulk of Energy Use
When you look beyond electricity to total energy consumption, including heating buildings, fueling cars, and powering industry, the picture changes dramatically. Switzerland produces almost no fossil fuels domestically and imports virtually all of its oil and natural gas.
In 2022, the country consumed over 2 million tonnes of heating oil and nearly 6 million tonnes of motor fuels. Diesel alone accounted for about 2.6 million tonnes, gasoline around 2 million tonnes, and aviation fuel roughly 1.4 million tonnes. These figures reflect a country where cars, trucks, planes, and oil-fired boilers still burn through enormous quantities of petroleum products every year.
Natural gas plays a major role in keeping Swiss homes and businesses warm. Residential heating alone consumes 45% of total natural gas use, with industry taking another 32% and commercial buildings about 20%. Transport accounts for a negligible 0.5%. Switzerland has no domestic gas production and imports everything through pipelines connected to the broader European network. Nearly all imported gas (95%) goes directly to end users rather than being used for electricity generation, which distinguishes Switzerland from countries that burn large amounts of gas in power plants.
The Winter Import Gap
Switzerland’s electricity system has a notable seasonal imbalance. In summer, when alpine snowmelt fills reservoirs and river flows peak, the country produces more electricity than it needs and exports the surplus. In winter, the situation reverses. Shorter days, lower water levels, and higher heating demand create a gap that Switzerland fills with electricity imports from neighboring countries, particularly France and Germany.
During the current winter period (October through March), Switzerland imported roughly 5,980 GWh of electricity on a net basis. This winter dependency has become a growing concern, especially as nuclear capacity shrinks. Expanding solar, wind, and alpine storage capacity are all part of the conversation about closing this gap, but for now, winter imports remain a structural feature of the Swiss energy system.
Solar and Other Renewables
Solar photovoltaic capacity has been growing rapidly in Switzerland, though it still contributes a relatively small share of total electricity compared to hydro and nuclear. The country’s Energy Strategy 2050 framework aims to scale up renewables significantly while phasing out nuclear over time and reducing overall energy consumption. Wind energy remains limited, partly due to public opposition and the country’s dense population, but rooftop and alpine solar installations have accelerated in recent years as federal incentives and streamlined permitting have taken effect.
How It All Adds Up
Switzerland’s energy profile has two faces. Its electricity grid is one of the cleanest in Europe, dominated by hydropower and nuclear with minimal carbon emissions during generation. But its total energy consumption still leans heavily on imported oil and gas, particularly for transport and heating. Roughly half of the country’s final energy use comes from fossil fuels, a reality that persists despite the green reputation of its power grid.
The transition away from fossil fuels in heating and transport is well underway. Heat pumps are replacing oil boilers at an increasing rate, and electric vehicle adoption is climbing. But the scale of oil and gas consumption means this shift will take decades to complete, and Switzerland’s energy security will continue to depend on imports, whether of fossil fuels, electricity, or both, for the foreseeable future.