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What your battery will really do
Every light EV ships with a number. Forty-five kilometres. Sixty. A hundred, if the marketing team was feeling brave. Then you ride the thing on an ordinary Tuesday, get maybe two thirds of that, and start wondering what you did wrong.
Nothing. That number was measured in conditions you will never once ride in. This little tool gives you an honest figure for your battery, your hills and your headwind. Then the app plots the actual route.
01Where the missing kilometres go
Picture the test that produced the number on your box. Flat track, no wind, a light rider, a fresh battery, a mild afternoon, and a gentle, constant 20 km/h. Every one of those is a best case, and stacking them is how you get a headline figure. Reality removes them one at a time.
Hills are the obvious thief. Climbing costs energy in a way flat riding simply doesn't, and a short steep wall costs far more than a long gentle rise of the same height. The pull out of a valley toward Ath will empty a pack faster than any distance on the canal ever will. Then there's the wind, which nobody accounts for and everybody feels. Air resistance grows with the square of your speed, so pushing from 15 to 30 km/h roughly quadruples the drag you're paying for. Turn into a stiff breeze off the water and you can watch your range fall in real time.
Cold is the quiet one. Below about five degrees the chemistry inside the pack simply hands over less energy, and a January morning can pocket twenty or thirty percent before you've turned a wheel. Add a heavier rider, a bag of shopping, the stop-start of town traffic, and it all adds up. And every battery fades a little each year. None of this is a fault. It's just the gap between a laboratory and a life.
02The number that actually matters
Here's the thing the box never tells you: how far you can go is the wrong question. How far you can go and still get home is the right one. That's why the tool gives you a comfortable round trip and a turn-back point, not just a raw maximum.
The rule the app rides by is simple. Never plan to arrive on empty. Keep a reserve and turn around at roughly 40% of battery, so the wind that helped you out and now fights you home doesn't leave you pushing a very heavy scooter up the last kilometre in the dark. Spend the outward leg on about 60%, keep 40% for the return, and the day stays a pleasure instead of a lesson.
FAQ
Did I get a dud battery?
Almost certainly not. If you're twenty to thirty percent under the rated figure in normal conditions, that's normal. Worry only if the drop is sudden, or the pack has swollen, or it smells of anything at all. Then stop using it and have it checked.
How do I find my battery's size in watt-hours?
Multiply the voltage by the amp-hours. A 48 V pack rated at 15 Ah is 48 × 15 = 720 Wh. Both numbers are usually printed on the battery itself, or in the spec sheet you've probably lost.
Does cold really cost that much?
Yes, more than people expect. On a properly cold morning you can lose a quarter of your usable range before you factor in anything else. Keeping the battery indoors until you leave, rather than in a freezing shed overnight, buys some of it back.
Now plot the real thing
The estimate gives you the shape of the day. The app draws the actual route, the real climbs and today's wind.
Open the app