Digital Twins: What, Why, Where… and Most Importantly, How on Earth?

By Carolin Treichl, EVP EMEA at Kapsch TrafficCom

Digital twins — the living, breathing, data‑powered “mirror universe” version of your city’s mobility system — are no longer just something consultants whisper about at conferences. They’re actually happening across Europe. And when they work, they’re basically a superpower: predicting congestion before it happens, testing policies without causing public outrage, and optimizing multimodal chaos into something that looks almost… manageable.

But of course, nothing is ever that easy. Cities still face the usual headaches: messy data, ancient IT, not‑enough‑nerds, complicated procurement, and the eternal burden of keeping the twin up‑to‑date (because even digital clones need maintenance). Everyone’s talking about it, but few feel they truly “get” it. So here’s a digestible tour of what digital twins are, why they matter, where they already work, and how to move yours from “pilot project” to “actual functioning thing.”

For those who have more than 7 seconds - here further details:

1. What a Digital Twin Actually Is — And Why Mobility Desperately Needs One

A digital twin is basically your city’s mobility system… but without the potholes, budget complaints, and angry phone calls. It’s a virtual replica that gets smarter every time real‑world data flows in. We’re talking:  traffic lights, detectors, floating car data, buses, trams, weather tantrums, concerts, football games — the whole urban circus.

Unlike old-school static models (the ones that politely update every election cycle), a digital twin thinks in near real time. It can:

• simulate “what if” scenarios,
• test detours before destroying everyone’s commute,
• prep the perfect traffic plan for Beyoncé concerts, weather chaos, or spontaneous construction,
• and help cities choose the least horrible option.

European pilots already show faster incident response, shorter delays, and fewer emissions — all from trying things out in the simulation first instead of gambling with actual drivers. And clients love simulation because… well, it’s cheaper than apologizing for a year of failed roadworks.

Why now? Because urban mobility today is basically a hyperactive toddler: micromobility everywhere, on-demand everything, never-ending construction, and climate surprises. Old reactive systems just can’t keep up. With a digital twin, cities get a shared “mission control” where traffic managers can test ideas before unleashing them onto real streets.

2. Real‑Life Examples: Digital Twins Who Are Already Saving Cities’ Sanity

Europe has already hosted some high‑profile pilots under the EU-funded DUET program. The stars of the show: Athens, Flanders, and Pilsen.

Traffic Superpowers These Cities Gained:

• Scenario testing + real‑world validation (“Let’s close the bridge virtually first, to see how badly people will scream.”)
• Evidence-based planning with air quality, noise, and traffic data  (Finally! Decisions not based on “gut feeling.”)
• Public engagement tools Citizens could actually see and comment on changes — increasing acceptance and reducing pitchfork activity.

Concrete Outcomes:

• Flanders (Ghent): Simulated closing a major bridge. Tested full, partial, and “maybe we shouldn’t touch it” scenarios. Picked the best one. Won an award for it.
• Pilsen: Graduated from flat 2D maps to fancy 3D twins showing real‑time traffic, air quality, and noise. Result: less congestion, less pollution, fewer headaches.
• Athens: Used the twin to support green routing — reducing congestion and environmental impact. A rare win‑win in mobility planning.

Meanwhile, cities like Zurich, Santander, and Helsinki are also playing in the digital twin playground — simulating scenarios and supporting smarter decisions.

3. The Challenges (aka: Why Everyone Isn’t Doing This Already)

Digital twins are powerful — but they also expose some uncomfortable truths:

• Data Quality & Integration: If your data is a chaotic mess, your twin will be too. Think of it like feeding a robot only pizza and energy drinks — it will malfunction.
• Organizational Silos: Transport, environment, utilities — they all need to talk. Sometimes they don’t. A twin forces a family meeting.
• Skills & Expertise: Cities need simulation experts, AI people, data scientists — and public administrations aren’t exactly overflowing with them.

With the right strategy and the right tech partner, however, these problems shrink dramatically. Cities don’t need all the skills in-house — they just need someone who can guide them through the jungle.

4. So… How Do We Move from Pilot to Real Platform?

Three big steps:

• Fix the data.
  A digital twin is only as good as the data it eats. Invest in quality, make standards open, and use the sensors you already have (or upgrade — ideally with best‑in‑class ones).
• Start with one high‑impact use case.
  Don’t try to solve everything at once. Pick the biggest pain point, fix it well, then expand. Just like the Connected Vehicles project on the German Autobahn — it started with road works warnings, then scaled.
• Use available funding.
  There’s a ton of national and EU money earmarked for digital twins and smart mobility. Use it. That’s what it’s there for.

If you want to dig deeper, check out the excellent (and free!) book “Decide Better: Open and Interoperable Local Digital Twins” — perfect for anyone wanting to geek out on digital twins without apology.