Cycling on nuclear energy, is that possible?
Nuclear energy is very compact, you can generate hundreds of thousands of times more energy per kilogram of nuclear fuel than from fossils. Moreover, the main argument, nuclear energy is intensely hated by Jesse Klaver, the Belgians and the Germans. What does it take to run your bicycle on nuclear energy?
Nuclear Power Batteries
It may surprise you, but compact nuclear-powered batteries, beta-voltaic batteries, have been around for a long time. They are used in places where it is especially important that a device continues to work, for tens or even hundreds of years, without running out of energy. Think, for example, of emergency lighting or a pacemaker.
Betavoltaic batteries are filled with a special radioactive isotope, which emits beta rays. beta radiation? Radiation is scary right? The answer: yes, and no. You certainly don’t want to ingest beta-emitting radioactive substance, but as long as it’s in a shell, there’s nothing to worry about. Beta radiation is nothing more than… electrons. The particles that revolve around atomic nuclei and move in a wire.
Unlike a chemical battery, where electrons are released through a chemical reaction, in a beta-voltaic battery, electrons are released because an atomic nucleus breaks apart. These electrons bang against an electrical conductor, and lo and behold, there is a circuit on which you can, for example, burn a bicycle light. Or, of course, have a bike ride on it.
Now there is only one small problem. Beta-voltaic batteries are usually very weak. Think microwatts of power. That is not a problem for a pacemaker or a sensor. They don’t need much energy. But for the 250 watts for the motor of a good electric bicycle, from Gazelle or Kalkhoff for example, it is really too little.
So should we write off nuclear energy for your bicycle? No, because there is another solution.
Nuclear-powered bicycle: plutonium-238
What do I have on my bike now? Driving with an atomic bomb in your frame? It doesn’t really sound like a good idea.
relax. Not all plutonium is Pu-239, the isotope used in nuclear bombs. There’s an isotope that slowly disintegrates and only gets really, really hot. We’re talking about plutonium-238, which has a neutron less than Pu-239. This slowly decomposes under the emission of alpha particles.
Alpha particles are in normal human language: the atomic nuclei of helium, the stuff you put in helium balloons and which gives you a high-pitched voice. You can stop them with a sheet of paper.
So harmless, as long as those alpha particles are not released inside your body. And, not to be mistaken, the power density of pure plutonium-238 is high, about half a watt per gram.
That is, if you could harness all the energy, a chunk of plutonium the size of a ping-pong ball would power your bicycle. Unfortunately, that is not possible, because the energy is released as heat. You have to convert it into electricity first. Although that is of course nice in the winter, a bicycle with heated seats.
Our best thermocouples, which are used in the radioactive thermal generators of the Mars rovers, for example, only achieve a 4-7 percent efficiency. So that ping pong ball better be a tennis ball.
And then, of course, there is the cost. Because plutonium-238 is quite expensive. You can easily pay more than ten million euros per kilo.
No problem if your name is Elon Musk, but not so handy in your Batavus or Sparta if you still have to pay off your mortgage every month.
Next best for a nuclear-powered bicycle
Your lifelong nuclear energy battery for your bicycle will therefore have to wait a while. Fortunately, there are excellent alternatives. Such as bicycles equipped with a double Power Tube battery from Bosch. Or another bike with a good battery.
Think, for example, of a Cube mountain bike or a Stromer speed pedelec. With a double Bosch PowerTube you can ride hundreds of kilometers without having to recharge your bike. Although without seat heating, you don’t have to worry about radioactivity. And that, of course, is a lot nicer to cycle.
