Is It Worth Driving Further to a Faster Charger? The Detour Maths

EVDANCE Insights · EV Charging Guides

Sometimes, yes. A faster charger further away pays when the time it saves at the plug is larger than the extra driving time — plus the few minutes it takes to charge the detour miles themselves. On a large top-up the saving can be tens of minutes, because DC fast charging as a class adds roughly 180 to 240 miles of range per hour. On a small top-up, it almost never pays.

The Two Sides of the Trade

• What the detour costs. Extra miles take driving time, and they come out of the battery first — so the energy for them has to be charged back during the stop.
• What the faster stall returns. A higher average rate across the session — not the badge number. Your car’s own maximum and its charging curve set that average, as how fast a DC fast charger is and why charging slows after 80% both show.
• The bigger the top-up, the more the rate matters. Rate differences multiply by the energy you take on. Ten minutes saved per 10 kWh is an hour on a 60 kWh stop — and almost nothing on a splash-and-go.

One Worked Example

Say you need about 30 kWh to reach the next leg comfortably — an assumed amount for the example, not a figure for your car. A slower fast charger sits on your route; a faster site means a 10-mile round detour. Using illustrative session averages (your car may sit lower on either):

The detour wins here by about ten minutes. Halve the top-up to 15 kWh and the plug saving halves while the detour cost stays fixed — now the near charger wins. That is the whole decision, every time.

When the Faster Stall Cannot Pay You Back

• Your car’s limit is the lower number. If your car accepts 80 kW at most, a 350 kW stall gives you 80 kW. The saving shrinks to whatever the near charger was costing you above that.
• The fast site is busy or sharing. Paired stalls split power, and a queue spends your saving before you plug in. Check the site’s live status before you commit — the DOE AFDC Station Locator lists stations and connectors along a route.
• The battery is cold. A cold pack charges slowly at every stall alike. Preconditioning on the drive over can lift the faster stall’s rate — but count the drive honestly, as part of the detour.
• You only need a little. Small top-ups are dominated by the fixed costs: driving there, plugging in, paying.

The Same Logic, at Destination Scale

Sites run this calculation from the other side. A compact DC unit such as the EVDANCE EV-RHDC30K-L (22 kW DC, OCPP 1.6J) at a hotel or workplace removes the detour entirely: the car charges where it already parks. It will not match a highway stall’s rate, and it does not need to — zero detour minutes is a strong hand. Site hosts can see the range on our commercial charging page.

Frequently Asked Questions

Will a 350 kW charger charge my car much faster than a 150 kW one?

Only if your car can use the difference. Your car’s maximum rate and its charging curve decide what it draws from either stall; many cars spend most of a session well below both badges.

How do I estimate the saving before I set off?

Divide the energy you need by each stall’s realistic average rate — not its badge — and compare the difference with the detour’s driving minutes plus a few minutes to charge the detour miles. If the figures are close, take the nearer charger: certainty beats theory.

Is the detour worth it in winter?

Less often. A cold battery caps every stall, so the faster site’s advantage shrinks until the pack warms. If your car preconditions on the way to a chosen charger, the longer drive may warm the pack — but that time is still part of the cost.

Related Reading

• How Fast Is a DC Fast Charger?
• How Do DC Fast Chargers Work?
• Why Does EV Charging Slow Down After 80%?
• What Is a Rapid EV Charger? Slow, Fast, Rapid and Ultra-Rapid Explained

Sources & Standards

• U.S. DOT — Charger Types and Speeds
• U.S. DOE AFDC — Station Locator