Power exports by Europe's biggest economy, which shares borders with nine countries, fell 11.6% to 52.5 TWh last year compared with 59.4 TWh in 2019, the energy regulator, called the Bundesnetzagentur, said in a publication on Saturday.
Meanwhile, electricity imports into Germany in 2020 increased by 38.8% to 33.6 TWh, compared with 24.2 TWh in the prior year.
Cross-border trade is especially strong with France, which still bets on nuclear power - shunned in Germany for safety concerns which resulted in its plan for a scheduled withdrawal.
Under the nuclear exit, three reactors out of Germany's remaining six are due to close at the end of 2021.
The country has also committed itself to ditching carbon-polluting coal generation by 2038 to meet climate protection obligations and decarbonize its energy systems.
Under exit deals agreed between the government and coal utilities last year, a total 4.8 GW of hard coal capacity stopped marketing its output as of Jan. 1, while the plants' existing delivery obligations will be worked off in early 2021.
Under a separate deal to pull out of brown coal, RWE decommissioned its Niederaussem D 300 MW lignite plant on Dec. 31.
Berlin's strategy entails rolling out more renewable capacity such as wind turbines and solar panels and to improve cross-border flows to spread localized and temporary supply risks.
Renewables did increase their share of power by 3.2 percentage points last year, arriving at 49.3%, the Bundesnetzagentur noted.
