Environmental impact

Cars are a major cause of urban air pollution, with all types of cars producing dust from brakes, tyres and road wear. As of 2018update the average diesel car has a worse effect on air quality than the average gasoline car But both gasoline and diesel cars pollute more than electric cars. While there are different ways to power cars most rely on gasoline or diesel, and they consume almost a quarter of world oil production as of 2019update. In 2018 passenger road vehicles emitted 3.6 gigatonnes of carbon dioxide. As of 2019update, due to greenhouse gases emitted during battery production, electric cars must be driven tens of thousands of kilometers before their lifecycle carbon emissions are less than fossil fuel cars: but this is expected to improve in future due to longer lasting batteries being produced in larger factories, and lower carbon electricity. Many governments are using fiscal policies, such as road tax, to discourage the purchase and use of more polluting cars; and many cities are doing the same with low-emission zones. Fuel taxes may act as an incentive for the production of more efficient, hence less polluting, car designs (e.g. hybrid vehicles) and the development of alternative fuels. High fuel taxes or cultural change may provide a strong incentive for consumers to purchase lighter, smaller, more fuel-efficient cars, or to not drive.

The lifetime of a car built in the 2020s is expected to be about 16 years, or about 2 million kilometres (1.2 million miles) if driven a lot. According to the International Energy Agency fuel economy improved 0.7% in 2017, but an annual improvement of 3.7% is needed to meet the Global Fuel Economy Initiative 2030 target. The increase in sales of SUVs is bad for fuel economy. Many cities in Europe, have banned older fossil fuel cars and all fossil fuel vehicles will be banned in Amsterdam from 2030. Many Chinese cities limit licensing of fossil fuel cars, and many countries plan to stop selling them between 2025 and 2050.

The manufacture of vehicles is resource intensive, and many manufacturers now report on the environmental performance of their factories, including energy usage, waste and water consumption. Manufacturing each kWh of battery emits a similar amount of carbon as burning through one full tank of gasoline. The growth in popularity of the car allowed cities to sprawl, therefore encouraging more travel by car resulting in inactivity and obesity, which in turn can lead to increased risk of a variety of diseases.

Animals and plants are often negatively impacted by cars via habitat destruction and pollution. Over the lifetime of the average car the "loss of habitat potential" may be over 50,000 m2 (540,000 sq ft) based on primary production correlations. Animals are also killed every year on roads by cars, referred to as roadkill. More recent road developments are including significant environmental mitigation in their designs, such as green bridges (designed to allow wildlife crossings) and creating wildlife corridors.

Growth in the popularity of vehicles and commuting has led to traffic congestion. Moscow, Istanbul, Bogota, Mexico City and Sao Paulo were the world's most congested cities in 2018 according to INRIX, a data analytics company.