Tesla and the US electricity grid: how the impact of charging is changing

An electric car can reduce the emissions associated with its journeys without a new battery or a software update. This happens when the electricity used to charge it becomes less polluting: the vehicle stays the same, but what supplies the socket changes. Comparing the US grid in 2017, the year of the first Model 3 deliveries, with 2025 shows how this effect can matter over time.

Coal plays a much smaller role in the United States

In 2017, US coal-fired power stations generated around 1,206 terawatt-hours of electricity. By 2025, that had fallen to around 735 TWh, a reduction of 39%. Total electricity generation increased over the same period, so coal’s share fell even more sharply: from almost 30% to around 16.6%.

The change is not simply a shift from coal to renewables. Natural gas rose from around 32% to 41% of electricity generation, becoming even more central to the US system. This distinction matters: a grid with less coal is not automatically a grid without fossil fuels.

Solar grows as wind passes 10%

Over the same period, utility-scale solar generation rose from around 53 to 300 TWh: more than five times its 2017 level. Its share of electricity generation increased from around 1.3% to 6.8%. Including small-scale solar installations brings the 2025 figure to around 393 TWh; the two measures must be kept separate when comparing percentages.

Wind generation also increased, from around 254 to 462 TWh, a rise of almost 82% and a share exceeding 10% of the total. Nuclear and hydroelectric power continue to contribute, but their generation did not increase compared with 2017. The grid’s transformation therefore reflects changes across several sources, each following a different path.

What changes for a Tesla already on the road

For owners of a Model 3, Model Y or another electric car, the key point is that charging emissions do not necessarily stay at the level they were in the year of purchase. If emissions per kilowatt-hour of the electricity used decrease, the impact of subsequent miles can also fall, without replacing the car.

However, this national generation comparison cannot assign a precise CO₂ reduction to every Tesla. The local grid, charging time, actual vehicle consumption and charging losses all matter. Operational emissions are also only part of the environmental balance: manufacturing the car and battery, maintenance and end-of-life treatment require a separate assessment.

A long-term trend, without guaranteed improvement every year

One detail helps avoid an overly optimistic interpretation: US coal generation increased in 2025 compared with 2024, when it was around 652 TWh. The result remains far below 2017, but the path does not always move in the same direction.

These figures concern the United States and do not describe Italy’s electricity mix. The principle applies elsewhere too: as the emissions intensity of the electricity used falls, the operational impact of electric cars already on the road can improve. The actual benefit depends on how the grid charging them changes.