Nuclear power has been discarded for decades since the tragic accidents from the 80’s that led to numerous environmental damages in Ukraine and other parts of the world. Still, nowadays there is a trend of reviving nuclear power, to make it 100% safe and to convince people it’s worth investing in it, as an alternative to coal or petrol.
Ithaca, a NY-based company, is starting the production of the so-called “betavoltaics” – sources of nuclear power in the form of small batteries whose charge could last for as long as 25 years. Their technology has been tested by Lockheed Martin, an important military equipment manufacturer. Of course, these batteries will be used to power electrical circuits that protect military planes and missiles from tampering and reverse-engineering.
In the meanwhile, another company, called Widetronix, is trying to implement the nuclear technology into medical-use batteries. Their cells are powered by the decay of a hydrogen isotope called tritium into high energy electrons. Betavoltaic cells such as Widetronix’s use semiconductors to capture the energy in the electrons produced during the nuclear decay of isotopes just like solar cells capture the photons’ energy. Betavoltaic batteries can withstand harsher conditions than chemical batteries do, being available at any environment temperature.
Widetronix’s batteries are made up of a metal foil impregnated with tritium isotopes and a thin chip of the semiconductor silicon carbide, which can convert 30 percent of the beta particles that hit it into an electrical current. “Silicon carbide is very robust, and when we thin it down, it becomes flexible,” says Widetronix CEO Jonathan Greene. “When we stack up chips and foils into a package a centimeter squared and two-tenths of a centimeter high, we have a one microwatt product.” The prototype being tested by Lockheed Martin produces 25 nanowatts of power.Betavoltaics aren’t very powerful. They don’t have nearly enough power to drive a laptop or a cell phone. But their energy density is high: they store a lot of energy in films just micrometers thick and can be made in very small packages. “We’re focusing on places where you need a very long life and energy density,” says Greene.
The risk of using betavoltaics drops as researchers gain more and more experience from using the radioactive material. The only problem still remains their disposal: where are we going to put all the unused batteries, or what are we going to do with the damaged ones? Isn’t this going to affect us? If these questions could be answered with certainty and scientific evidence, I see no reason why we shouldn’t use portable nuclear power everywhere. Until these questions will be answered, I’ll stick to chemical batteries.