What would happen if everyone drove an electric car?

Replacing the entire light vehicle fleet would eliminate tailpipe emissions, which is the largest single source of nitrogen dioxide in most cities and a major contributor to urban particulates — though tyre and brake wear would continue, and heavier vehicles produce more of it. Electricity demand would rise substantially, with estimates for full fleet electrification in developed economies typically in the range of 20 to 30 per cent of current generation, which is large but comparable to demand growth absorbed historically over a couple of decades. The binding constraints are distribution rather than generation: local networks and charging availability, particularly for households without off-street parking. Lifecycle emissions depend heavily on the generating mix, and battery production is materially demanding, requiring lithium, nickel, cobalt and graphite at volumes that would need mining capacity to expand faster than it historically has. The net climate benefit is positive in essentially every published assessment, and its size varies with the grid.

How confident this is

This is a reasoned extrapolation rather than an observation. The mechanism is understood, but the scale of the consequences depends on assumptions that could reasonably be argued differently.

Society

• What would happen if everyone stopped having children? Schools would empty within a decade, the workforce would begin shrinking in about twenty years, and the last human would die in roughly a century.
• What would happen if everyone stopped eating meat? A large drop in agricultural emissions and land use, offset by disruption to a billion livelihoods and some regions with no alternative.
• What would happen if antibiotics stopped working? Routine surgery, chemotherapy and childbirth would all become far more dangerous — this is already happening slowly.
• What would happen if all jobs were automated? The production problem would be solved and the distribution problem would not — nobody has demonstrated the second half.
• What would happen if half the world's population disappeared? Not abundance — the collapse of specialised supply chains, because modern systems need specific people rather than a certain number of them.
• What would happen if the world's population doubled overnight? Food is the binding constraint — global production feeds around 8 billion, and doubling demand cannot be met from existing stocks.
• What would happen if everyone lived to 150? It depends entirely on whether those are healthy years — extended lifespan without extended healthspan makes almost everything worse.
• What would happen if everyone worked a four-day week? Trials generally show output holding steady with better wellbeing — but the results come from office work, not from hospitals or factories.
• What would happen if everyone spoke the same language? Trade and science would get modestly easier, and roughly seven thousand languages worth of knowledge would be lost.
• What would happen if nobody paid taxes? Everything funded collectively stops — roads, courts, defence, schools, health systems and pensions — within weeks to months.
• What would happen if all borders opened? Economic models suggest a very large rise in global output, and nobody can model the political response, which is the part that would decide it.