Charging where you arrive: a socket, a hotel, a campsite

Energy delivered is power times time. That multiplication is routinely underrated, because power appears on a display and time does not. A modest connection working for twelve hours delivers more than a powerful one during a coffee stop — and it does so while nobody stands waiting beside it.

That fixes the order for any trip: first settle where you will sleep and whether there is power there; then plan the route. Do it the other way round and you build a journey out of charging stops, then wonder why it was tiring.

The second advantage is technical. A low charging rate means a low C-rate, little waste heat and a charging window you can choose freely — including the option of stopping short of the topmost percentages. It is the gentlest treatment a pack can get while travelling.

Across much of Europe the voltage and the frequency are the same. The shape of the domestic socket is not: Switzerland has its own system with offset pins, France and Belgium use an earthing pin rather than side clips, Italy has several diameters living side by side, and Denmark, Ireland and the United Kingdom each have another pattern again. The travel adapter from your wash bag is not built for this job.

What differs is not the shape but the sustained load. An adapter for a phone charger carries a tenth of what a mode 2 cable pulls for hours on end. Cheap travel adapters have small contact faces and springy sheet-metal contacts; under continuous load they get warm, and warm is the stage before scorched. Charging from a domestic socket abroad needs an adapter rated and marked for the cable's continuous current.

Then there is what sits behind the socket, which you cannot see. In older buildings several rooms share a circuit, terminals have aged for decades, and a residual-current device is sometimes missing altogether or is not of the type a car with a DC link requires. The owner's permission is not an assessment of the wiring.

Campsites, workshops, farms and many underground car parks carry a blue or a red industrial socket. Blue carries one phase, red carries three. Both are built for sustained load, with large round contacts, a locking ring and a seal — precisely the qualities a domestic socket lacks. Where one exists, it beats a household outlet in every respect.

The current rating is printed on the socket, and it states what the connector permits — not what the distribution board behind it is actually fused at. On a campsite the per-pitch fuse is often far smaller than the connector's shape suggests, because the whole site hangs off one supply. So the question about the fuse belongs at check-in, not over dinner.

Mode 2 cables can be fitted with adapter heads for both patterns. They are the most worthwhile item in a travel kit, because they turn an improvised arrangement into a proper one. What they cannot do is raise the power. The on-board charger remains the ceiling, and on a single-phase blue socket even a three-phase car charges on one phase.

“Do you have charging?” is the wrong question, because the answer is almost always yes and almost never means what the guest meant. A hundred-room hotel with two charging points has charging. What somebody arriving in the evening needs to know is something else.

Useful questions are the ones that force a number or a clear no. How many points, which connector, AC or DC, reservable or not, behind a barrier or freely accessible, tied to a particular card or open to anyone. And the most useful one last: is there also an ordinary socket in the garage that a guest may use overnight if the points are taken?

“Two points, both Type 2, no reservation” is useful, because you can plan around it: if both are taken you drive to a public charger in the morning and the trip is unaffected. “We have charging” supports no plan at all, and is therefore worth nothing.

Most mode 2 cables and many cars let you set the charging current. On an unfamiliar installation that setting is the single most useful tool available: a lower current stresses the socket, the terminals and the supply far less, and it is the difference between an uneventful night and a warm outlet.

That you lose almost nothing by doing so follows from the same multiplication as before. Current times voltage gives power, power times hours gives energy. Across a long night even a cautiously set current adds up to a usable amount — enough for a day's driving on most trips.

Put your hand on the socket after half an hour. Hand-warm is normal, distinctly warm is a reason to lower the current further, and hot is a reason to unplug and give up on it. This check costs nothing and stands in for the technical information you were never going to get anyway.

The travel kit for an electric car is small, and it is useless on any day when one item of it is at home. So it lives in the car permanently, not in a cupboard.

One item of the kit is not an object: the maximum AC current the car accepts and the number of phases. Without that you can neither judge a socket nor choose a setting. It is in the vehicle documents and takes two minutes to look up.

A trip where the car charges every night only needs the day's energy while on the move. That is a different kind of plan: the day is governed by the distance you meant to cover, not by the car's range. The rapid-charging stop drops from being part of the plan to being an exception.

This matters most where the rapid-charging corridors are thin. Away from the main axes, on islands and in mountain valleys, the socket at the destination is not a fallback but the actual infrastructure. If that is where you are going, choose the accommodation by its connection rather than the other way round.

And one rule stands for the case where nothing works on arrival: never plan the last leg on whatever is just barely enough. Arrive with a real reserve and you have a choice the next morning. Arrive without one and you do not.