The idea for my EV charging simulator VoltSim didn’t come to me while sitting at a desk, nor did it stem from a desire to simply build some random tool for electric cars. It arose from a fairly ordinary observation on a film set. I was sitting there, watching the activity around me, and at some point I started paying attention to the shuttle vehicles. Not the big equipment transporters, not the trucks, not the vehicles that had to move heavy equipment, but the classic passenger shuttles that were constantly traveling back and forth between the set, base camp, production routes, and short trips.
These were the kinds of vehicles you see all the time on such productions. Diesel vans, often Mercedes Vitos or similar models. Practical, spacious, rugged, familiar, readily available. So, nothing unusual at first glance. I don’t want to pretend that the decision to use such vehicles is fundamentally wrong or absurd. Film productions are complex. Things have to work. People need to get to the set on time, actors need to be picked up, the crew needs to get from A to B, things need to be organized in between, and no one wants a vehicle in such a workflow that suddenly isn’t operational. From this perspective, I understand why people turn to what’s tried and true.
Still, something about it wouldn’t let me go. Some of these shuttles drove very short distances and then just sat around afterward. Not just short—not even five minutes—but sometimes significantly longer. I started roughly timing it, just out of curiosity. On set itself—not at the unit base, not where catering, makeup, production, and the actors’ areas are, but right where filming was taking place—some of these vehicles sat idle on average somewhere between twenty minutes and an hour without being visibly used. Sometimes even longer. Of course, this wasn’t a scientific measurement series with a formal record, but it was noticeable enough to raise a question.
If a shuttle sits around for twenty minutes, forty minutes, or even an hour, is that just downtime? Or could that time also be charging time?
That’s exactly where the actual idea began for me. I didn’t want to simply claim that an electric shuttle would be better. That would have been too simplistic for me. Especially when it comes to electric cars, many discussions quickly become ideological. Some act as if electric mobility is always and everywhere the perfect solution. Others act as if charging would never work and as if every electric vehicle were an organizational risk in everyday life. But I was interested in the area right in between. Not the big debate over principles, but the concrete situation: A shuttle is sitting idle. It travels short distances. It’s on the move in the city or at least near the city. It often carries only a few people. What if we didn’t view these idle times as a problem, but as part of the system?
So I started using an app to check where charging points were located nearby. Not as a finished plan, but just as a reality check. In urban locations, the result was surprisingly unspectacular. The nearest usable charging points were often not far away at all. In some cases, fast chargers or standard charging points were located roughly within two kilometers. That’s roughly a five- to six-minute drive, depending on traffic and the city layout. Even if you factor in the round trip—so maybe ten to twelve minutes—with downtime of twenty minutes or more, you suddenly have a time window left over that you can at least consider.
In rural areas, of course, the situation was different. There, the nearest major charging stations were more like five or six kilometers away. That’s a different calculation altogether, because you’re no longer just driving around the corner. But even there, my immediate reaction wasn’t: impossible. Rather: It depends on the situation. If a vehicle isn’t needed for a longer period anyway, a slightly longer drive to the charging station can be worth it. But if it’s needed spontaneously at any time, the situation is different. That’s exactly why I didn’t want to rely on gut feeling, but rather a way to visualize such scenarios.
What’s important to me here is the distinction. I’m not talking about switching every film set completely to electric. I’m not talking about trucks, not about heavy technical vehicles, not about special transports, and not about shoots somewhere in the middle of nowhere where there’s no suitable infrastructure for miles around. Such cases are real and must be viewed differently. I was concerned with the shuttles that travel short distances in cities or suburban areas—those that shuttle between the set and base, pick up people, transport small items, perhaps drive from the production office to the set, or operate within a manageable radius. It was precisely these vehicles that struck me as interesting because they were often not operating at full capacity.
That was actually the point that preoccupied me the most. There’s a relatively large diesel van with a two-liter engine driving through the city, sometimes with just the driver and one or two other people. It’s designed to carry significantly more people or luggage, but at that specific moment, it’s making a short shuttle run. Then it sits idle again. At the same time, there’s a lot of talk in the industry about green production, about more sustainable processes, about more conscious decisions. And yet, in everyday life, you still see these small contradictions, which probably don’t arise out of malice at all, but simply because existing processes keep running.
It is precisely these contradictions that I find fascinating. Not to point a finger at anyone. A film set is not a theoretical ideal model. It is loud, fast-paced, expensive, stressful, and full of interdependencies. If a shuttle isn’t working, it’s not just a minor inconvenience; in the worst case, it can delay operations. That’s why the conservative decision is often understandable. But understandable doesn’t automatically mean optimal. And if a vehicle makes many short trips every day and sits idle a lot in between, then it’s at least worth doing a sober calculation.
VoltSim was born out of this consideration.
I wanted to build a tool that doesn’t claim to already know the answer. Not a tool that says: Electric is always better. Not a tool that pretends manufacturer data, charging capacities, and real-world conditions are always perfectly predictable. Instead, an EV charging simulator that makes it easier to answer a simple question: What happens if I charge a specific vehicle for a specific amount of time?
Because in such shuttle scenarios, the crucial question is often not how long a full charge takes. Of course, you could say that a large electric van takes a long time to charge from zero to one hundred percent. But how realistic is this scenario in everyday life? Most vehicles aren’t constantly driven until they’re completely empty and then fully charged. The range in between is much more interesting. What happens between ten and eighty percent? What does a quick stop accomplish? How much energy do you get in ten minutes? What happens in twenty minutes? And even if a shuttle is at a fast charger for just two or three minutes, the question is: Is that completely irrelevant, or does it already restore a usable amount of range?
These are exactly the kinds of questions I wanted to make visible with VoltSim. Not just with a number, but with a sense of the process. A vehicle has a battery. It has a maximum charging power. But it also has a charging curve that determines how much power actually reaches the battery in which range. A charging station can impose limits. The car can impose limits. The starting charge level plays a role. The target charge level plays a role. Consumption determines how much range is generated from the charged energy. And in the end, there’s not just the technical question, but also the practical one: Is that enough for the next assignment?
On a film set with multiple shuttles, things get even more interesting. You don’t necessarily have to assume that every vehicle must be electric or that every electric vehicle must always be immediately available. A mixed fleet would also be conceivable. Some vehicles could remain diesel-powered for special cases, as reserves, or for longer trips. Others could handle the short, predictable city trips electrically. If eight shuttles are in use, some could be actively driving, some on standby, and one or two charging. When a vehicle’s battery level drops below a certain threshold, it drives to the charging station while another takes over. This requires communication, of course. It requires good fleet management. But on a set, operations are constantly being coordinated anyway. So the question isn’t just whether a single e-shuttle can handle everything. The more exciting question is whether a small fleet could rotate intelligently.
Here, too, I don’t want to claim that this is always easy. You need drivers, planning, access to charging stations, appropriate contracts or charging cards, and you have to know what’s available nearby. Perhaps you don’t tie yourself to just one provider, but use multiple options to be more flexible. In Germany, providers like EnBW have a strong presence, but operations wouldn’t theoretically have to be limited to just one partner. The key would be that the system doesn’t function by chance, but is deliberately planned.
For me, this turned into a kind of thought experiment with real-world relevance. What if a shuttle’s downtime were viewed not just as waiting time, but as a resource? What if a short charging stop were not seen as an interruption, but as part of the shuttle plan? And what if we didn’t wait until we had a perfect setup with our own charging infrastructure to think about electric mobility, but instead looked at what would be practically possible even with normal urban operations?
VoltSim is my attempt to make these questions more tangible. The EV charging simulator is not intended to replace a perfect study or provide a blanket answer. It is meant to show what happens under certain assumptions. If a vehicle starts with a certain battery level, charges at a specific station, and has a certain consumption rate, then you can estimate how much energy is recharged and how much range that results in. You can see whether a short stop is completely irrelevant or whether it could actually make a difference in the daily routine.
For me, that’s also the real philosophy behind the project. Sometimes technical ideas don’t arise because you want to solve a huge problem, but because you notice a small inconsistency. Something doesn’t quite work in everyday life. You see large vehicles on short routes, long idle times, low utilization, and at the same time the demand to produce more sustainably. Then you can get upset about it, or you can try to make it visible. I chose the latter.
That’s why VoltSim is also part of Cold Enemy Gaming. For me, the site isn’t just a place for finished games or completed projects. It’s also a place for experiments, prototypes, and technical questions that occupy my mind. Games are often about making systems interactive. With VoltSim, it’s similar. Except that here, the system isn’t a game mechanic, but rather charging time, energy, range, costs, and vehicle comparisons.
In the end, it all started with a diesel shuttle sitting around on set. Then came the question of whether this downtime actually had to go to waste. This led to a search for charging points, the idea of quick intermediate charges, the concept of a mixed shuttle fleet, and finally the desire not just to discuss the whole thing, but to simulate it.
So VoltSim isn’t a statement that electric vehicles are always the right solution. It’s more of a tool to counter mere gut feelings. An attempt to make a typical discussion a bit more concrete. Not: “That’ll definitely work.” Not: “That’ll never work.” But rather: Let’s run the numbers.
And that’s exactly how my EV charging simulator came to be.
