To be, or not to be? That is the electron!
What will be the fuel of the future?
A question that was asked of me on numerous occasions last year.
Who am I to say? I ask myself.
Then again, who does have the answer to this trillion dollar question?
So, for what it is worth, here is my opinion. Let’s take a look into the crystal ball of science to see if we can find the answer.
To begin at the beginning...
Fuel is a store of energy. Einstein’s famous equation, E=mc2, tell us that energy is equivalent to matter. We also know that there are only three possible ways to release energy from matter:
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Combining matter with anti-matter: If our understanding of math and physics is correct, there should be an equivalent amount of anti-matter as matter in the Universe (we just don’t know where to find it). So, for every electron there should be (somewhere) a positron (anti-electron), and for every proton, an anti-proton, etc. When an electron and positron meet -keBANG! – the two particles mutually annihilate, and all matter and anti-matter efficiently convert to two photons of pure electromagnetic energy.
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Ripping apart or fusing together nuclei: All matter is made of atoms. All atoms contain most of their mass in their nuclei as protons and neutrons. To keep all these nuclear particles together, sharing a confined space, the largest force in the Universe is required: the nuclear force! If we play about with this force, and either split these nuclear bonds, or force new ones to form, then huge quanta of energy are released in the form of alpha, beta or gamma radiation.
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Relocate electrons and reposition their orbits: Electromagnetic force is what keeps the electrons inside atoms whizzing around their nucleus and not just flying around willy-nilly. If we get atoms to change the positions of their electrons, for example by making them chemically react, then we release energy in the form of photons – tiny particles that wobble off into space at different frequencies: high frequency radiation, like gamma rays and X-rays, through medium frequency wobbling, like UV, visible light and IR, and longwave frequencies like microwave and radiowaves.
OK, now that we have defined the various ways to release energy from matter, let’s analyze how probable it is that we humans can harness their potential.
Option 1: matter/anti-matter annihilation
In Star Trek and similar serious Sci-Fi films and literature, this method of energy-release is often used by warp-drive matter/anti-matter annihilation engines. This technology remains the stuff of sci-fi dreams and CERN experiments. Nevertheless, this phenomenon is used in modern medicine in the form of PET (positron emission tomography) that produces high resolution images of the body.
Chances of use: matter/anti-matter annihilation is extremely efficient at releasing energy, and therefore could be an ideal fuel of the future, but requires huge advances in current technology (we do not presently understand how to generate significant quantities of antimatter, or how to contain it). Chance of implementation in the next 10 years: 0.0001%.
Option 2: nuclear power
The second method, nuclear energy, is how many countries satisfy varying amounts of their electricity needs. Generally, huge nuclei of atoms of Uranium are split to release the energy. In research, the opposite version of nuclear energy, the fusion of very light nuclei to form more massive atoms, is being verified for its commercial use. In terms of transport, as far as I know, it is only Michael J. Fox’s DeLorean in the film Back to the Future that runs on a nuclear engine.
Chances of use: While small thorium-based reactors have been made, they are still inappropriate for cars and other vehicles. There remain several engineering problems, not least the shielding of the reactor to avoid the escape of high-energy particles. Chance of implementation within the next 10 years: 0.002%. However, here there is a caveat! Large-scale nuclear power production, whether fission (more likely) or fusion (future possibility), does and will produce vast quantities of electricity, which could be the fuel of the future for cars, thus making the relevance of nuclear energy as a transport fuel proportional to the type of engine used.
Option 3: electromagnetic power
Right, let’s cut to the chase. It is almost exclusively the third method of energy release, that of electromagnetic energy, which we use to power our cars. Humankind has developed two main engine types to harness this form of energy: the internal combustion engine and the electric motor. Let’s treat these two engine types separately.
The internal combustion engine oxidizes hydrocarbon molecules to form carbon dioxide and water. This chemical reaction is very exothermic, meaning it releases lots of electromagnetic energy in the form of heat (infra-red photons) causing the rapid expansion in the volume of CO2 and H2O product gases that drives the engine. Hydrocrabon fuels, whether diesel or petrol, are the result of photosynthetic conversion of solar light into chemical energy. These molecules have an unrivalled energy density and are easy to transport, making them an ideal means of carrying and storing energy. Existing infrastructure for production, distribution and storage of liquid hydrocarbons is extensive and resilient. For marine, aviation and heavy-duty road transport, the energy density of liquid hydrocarbon fuels represents a fundamental advantage that will be difficult to overcome even when considering significant advances in future battery technology (at least a 10 fold reduction in the weight of current batteries is required). For these modes of transport, the key requirement is to store the maximum amount of energy on-board in the smallest possible volume and weight. So, until matter/anti-matter annihilation or nuclear powered engines are developed, this means the future for such heavy-duty transport is in hydrocarbon fuels.
Passenger cars, however, do not have such high barriers regarding the energy density/overall vehicle weight ratio, and therefore a move from the internal combustion engine and hydrocarbon fuels to the electric motor and electricity is more likely. The main driver for this change is the need to reduce greenhouse gas (GHG) emissions and the contribution passenger cars currently make to these emissions. Electrification reduces these emissions to zero at the vehicle level; however electricity production itself can, but not necessarily must, result in GHG emissions. Therefore, difficult strategic decisions on sources of electricity (coal, nuclear, renewable) must be made, and effective storage must be developed – do not forget, an electron is a sub-atomic particle and behaves according to the strange laws of quantum physics. It is therefore a far greater challenge to store than molecules. Current technology seems to be at odds as to the best way to implement electrification of cars. There are two main methods: the use of batteries (where weight and raw material costs are challenges) or the use of hydrogen fuel cells (where the production and storage of hydrogen present difficulties). Interestingly, it appears that in the Far East, Japan has placed its bet on hydrogen fuel cell technology, with a commitment to the roll-out of 400 000 such vehicles in time for the Tokyo Olympics in 2020. Meanwhile, China appears to be investing heavily into the research and development of battery technology, including the strategic sourcing of the necessary raw materials. This technology competition should be closely watched and the lessons from it, carefully considered.
In the Czech Republic, there could be as many as eight new hydrogen fuel stations by 2023, rising to twelve by 2025. Indeed, the Czech Ministry of Transportation has committed support to the development of hydrogen fuel stations to the tune of 1.2 billion CZK, which is a significant investment considering the falling price of hydrogen fuel station construction and distribution costs. Global institutions, such as the Hydrogen Council, claim significant advances in the production and distribution of hydrogen and highlight its growing importance in the energy mix. And whilst most hydrogen is currently produced from fossil hydrocarbon sources, companies like ORLEN Unipetrol are working hard to optimize the production of hydrogen from alternative sources, such as the electrolysis of water.
Chances of use: Electromagnetic power, either in the form of hydrocarbon combustion or electricity is here to stay for a whole plethora of reasons regarding production, storage and distribution. Whereas heavy-duty transport will almost certainly continue to be dominated by the use of liquid hydrocarbon fuels, passenger cars could see change. The question is, what is the car engine of the future? Will it be internal combustion or electric motor? Much depends on the technology implementation experiments currently under way and the wider discussion presently being had in society. Chance of implementation within the next 10 years: Liquid hydrocarbon fuels: 100 % - they are the incumbent fuel of choice, and will be very difficult to replace. The electron/electrification: 30 % chance of mass implementation in the coming decade, however, ultimately looks very likely to replace hydrocarbon use, whether with hydrogen-based fuels or on-grid electricity.
Fancy a bet on the future of fuel?