Can a paceometer be a deterrent against speeding on the road?

By MUNGAI KIHANYA

The Sunday Nation

Nairobi,

15 June 2025

If you drive at 60km/h, how long would it take you to travel one kilometre? It’s easy to calculate: one hour has 60 minutes, thus 60km/h is the same as 60km in 60 minutes. Therefore, you will take one minute to cover one kilometre. We can then extrapolate this to 10min to travel 10km and so on.

Now, 60km/h is a fairly slow speed – not too slow that you feel as if you’re not making progress and not fast enough to feel that you’re progressing! If the vehicle speeds up to 80km/h, you begin to feel that you’re gaining ground. But, at that speed, how does that affect the time taken to cover 10km?

The math is the same as before: 80km in 60 minutes means 0.75 min (or 45sec) per kilometre. So, you will take 7.5min to travel 10km. You’ve added 20km/h and gained 2.5min.

If you accelerate by another 20km/h to reach 100km/h, you will now take 6min to travel 10km – a gain of 1.5min from the previous 7.5min. and if you reach 120km/h, now you gain just one more minute from 6 to 5 minutes. Clearly, the amount of time gained in equal increments of speed (the extra 20km/h) reduces the fast you are moving.

Road safety experts have been suggesting that the car speedometer should also include a “paceometer” on the display. That is, to show the time it takes to travel 10km at various speeds. Thus, the value “30min” be written next to the 20km/h mark; 15min next to the 40 km/h; 10min at the 60 km/h; 7.5min on the 80 km/h; 6min at 100 km/h; 5min at 120km/h and so on…

The reasoning is that, once drivers notice the diminishing returns of higher speeds, they will not be highly motivated to drive faster. Would this idea work? If it works, perhaps we should just do away with speed displays on the dashboard and replace them with travel time. After all, speed is a useless quantity to the motorist; What everyone is interested in is how long the journey will take. That’s why Google Maps shows time of travel between places.

Meanwhile, it is worth noting that many car manufacturers intentionally over-calibrate the speedometers by up to 10 per cent in an attempt to discourage speeding. That is, the car is actually doing, say 60km/h, the speedometer shows 66km/h; at 100km/h, the pointer is at 110km/h and so on.