Before we start…

To understand this, you need to know two key things. First, quantum computers are great at tackling incredibly complex problems that are impossible for the best classical computers. Second, do you know what a smart city is?

A smart city, a term that was on everyone’s mouth but has now lost some of its sparkle, is a city that uses technology to become more sustainable and efficient. This isn't about the intelligence of its residents but about using tech to make urban living better. Projects range from smart streetlights that use renewable energy and adapt to environmental conditions in real-time thanks to IoT technology, to moss structures designed to literally eat air pollution and turn it into biomass.

So, it makes sense that a smart city should have an efficient public transport network with simplified, fast routes to reduce the carbon footprint. Sounds simple on paper, but it’s incredibly complex. So complex that it needed to be demonstrated on a quantum computer.

And they did it! Thanks to the quantum experts at Accenture and the innovation team at Lantik, the Technology and Innovation Society of the Government of Biscay.

PIONEERS IN EVERY WAY

This team wasn’t just the first to make a proof of concept when there were hardly any, but also the first to create a quantum ecosystem of experts when no one else had the resources. This happened five years ago, but Lantik still leads, and today, Biscay is one of the global hubs for quantum technologies. It’s the region with the most access to quantum hardware.

And this isn’t only something someone from Bilbao would say (they’re known for being a bit exaggerated).

EVERYTHING FITS INTO A MATH MODEL

Back to the project. The goal was to show that a quantum computer could solve a complex problem and achieve a functional goal: improving life for the people of Biscay.

They decided to use the electric buses in the fleet for longer routes and the combustion ones for shorter routes, analyzing things like how to accelerate and brake to emit less carbon dioxide.

For the technical implementation, they first downloaded a map of Biscay with all the routes (happy that they didn’t use the timetable—that’s undecipherable even for a quantum computer) and developed a mathematical model including everything necessary. They added restrictions and requirements to help reduce the carbon footprint.

And they succeeded because it could run on a real quantum computer.

A PROJECT THAT WON'T EXPIRE

If you think this mission isn’t ambitious, think again. Modeling or mathematically translating all the requirements to make Bizkaibus routes more efficient, fewer in number, and faster by combining electric and combustion buses and including driving details to emit fewer pollutants is no small feat. And making this model run on a quantum computer is even bigger.

This achievement doesn’t have an expiration date. When quantum hardware becomes more mature and powerful, Biscay will just need to press a button, and the project can be executed. The Bizkaibus route you use daily to get to university or work will change—it’ll be faster and the bus will be less polluting. Your daily life will improve with less travel time, and your quality of life will get better because we’ll breathe cleaner air.