Although Leonardo da Vinci was one of the first to conceptualise a self-propelled vehicle, it wasn’t until 1769 that Nicolas-Joseph Cugnot built one with a steam engine. But it took another century for the modern automobile to be invented by Karl Benz in 1886. Cars have undergone rapid transformation ever since, both in terms of productivity—the output of Benz’s engine was 0.75 hp, which is just a fraction of the over 750 hp automobiles that one can drive today—and technology, with self-driving cars being touted as the future, but the engine process has not undergone many changes. Most vehicles still use a refined version of internal combustion engine developed by Benz, which primarily requires gasoline for energy. While the fuel was good enough when the number of vehicles were less, as population and aspirations have increased, so has the burden on gasoline. Though transportation is just one of the uses of the fuel—it’s also used for creating plastic and polymer compounds—we end up wasting more of the limited resource on running our cars.
Not that there has been no attempt to replace the fuel. For the past three decades, there has been research on replacing gasoline as the primary fuel for vehicles, but none of the alternatives—ranging from electric cars to ethanol—have come close to fuelling the automobile industry. Ethanol blending has been adopted by many countries—India is on its way to do so with the government planning to introduce E10 (10% ethanol blend) by 2020—but the fuel comes with its own set of problems. Ethanol, though a cleaner fuel than petrol, produces lesser energy, leading to higher consumption. Thus, a fuel with more ethanol blend gets consumed more than pure gasoline does. At a time when ethanol prices have been more than gasoline—according to Chicago Mercantile Exchange, ethanol’s settlement for November was at $1.65 per gallon as compared to $1.50 of gasoline—it becomes more expensive to blend ethanol. Moreover, ethanol is produced from synthesising of cane or corn, which are major agriculture produces. So, given the limited amount of its availability, dedicating more resources to ethanol also lead to less land for other crops. For a country like India, growing too much cane means using more water, leading to not only a food shortage, but also water scarcity.
As environment takes centre-stage in countries’ policy, research has picked up on finding a viable solution to the gasoline problem. Global carbon emissions have plateaued over the last two years—this is mainly due to slowdown in China, the largest carbon dioxide emitter—they are yet to reach a peak, given that demand from developing economies like India is growing. With the world still emitting over 35 billion tonnes of carbon via fossil fuels, countries are realising there is little that can be done in terms of signing energy pacts and more has to be done on the innovation front.
Electric cars, though, seems to be a promising alternative, but the cars do not have enough range and cities do not have the infrastructure to make them viable. Also, the batteries would need to be changed every few years, which would make them an expensive proposition. But electrics are not the only option, there are other fuels that are being experimented on to replace gasoline.
Experiments with biocrudes have been going on for the past decade. While scientists have used everything from tree extracts to algae to waste, none have been successful, as synthetic oil has not been able to produce the same kind of energy as conventional oil does. Besides, in some cases where biofuels or bio-oils have been successful, the cost of production has become a deterrent for it to become a viable technology. But recently, scientists at the US Department of Energy’s Pacific Northwest National Laboratory were able to produce biocrude oil from waste sludge. The process, using a technology called hydrothermal processing (HTP), converts waste into biocrude at high temperatures, which can be further refined using the existing system of refining petroleum products, thereby not adding to the cost of companies to install new machinery for processing. While the process in itself is cheap, it also releases methane gas as a by-product, which can be used by industries. But despite its many benefits, the technology, which has been in development for the past six years, is still far away from achieving the economies of scale needed for commercial development.
While ethanol was touted as the product to replace fuel, given its more environment-friendly nature, it has not quite disrupted fuel production or addressed environmental concerns. Researchers at the Oak Ridge National Laboratory in Tennessee, earlier this year, discovered a way to curb global emissions from surging by using carbon dioxide to produce energy. According to a paper published in ChemistrySelect, Oak Ridge team was successfully able to use carbon to produce ethanol, a biofuel used for blending with petrol. While this is not the first attempt to use artificial photosynthesis—University of Berkeley and Chicago have both made this breakthrough—what differentiates Oak Ridge research is the low-cost solution to producing the fuel. Unlike other experiments, which require various catalysts, Oak Ridge team was able to achieve an efficiency of 63% while producing ethanol at room temperature by using a single catalyst—copper nano-particles—along with electricity. The solution may not help in reducing carbon emissions—the end-product of ethanol combustion would still be carbon dioxide—but it would create a net zero impact as the end-product could again be synthesised to produce energy. More important, it would reduce the cost of ethanol, which is currently synthesised from corn or sugarcane. With a reduction in prices, countries like India can easily achieve their targets of blending ethanol without worrying about putting more crop for producing fuel. Moreover, it can lead to efficient utilisation of electricity, where excess capacity can be used to produce ethanol which can be converted back into energy whenever needed. While countries will still have to reduce their carbon emissions, carbon-ethanol can be an important step in that direction.
One of the most abundant resources on earth, nothing can be more efficient than water to use in our vehicles. Though it has been one of the most researched fuel-substitutes—there has been decades of research behind it—no one has come out with a viable solution using this resource. The closest that companies have achieved is an HHO gas kit, which still uses gas, but requires much less quantity than before. The process in this case breaks down saline water to produce Brown’s Gas to burn with gasoline. The US Navy had developed a technology to create a hydrocarbon fuel cell using sea water. But even if water cannot be used as a direct source of energy, it will be used to power fuel cells which would require an additional catalyst.
With most of these technologies requiring yet another decade to be fully developed, petroleum is here to stay for a few more years, as are Benz engines. Moreover, with countries finding new technologies to extract gasoline—fracking used by the US is one of them—and prices of crude coming down, petrol may not go down so easily. Also, with HHO cells helping cars become more efficient, gas may not be completely phased out. So, while future fuels may be becoming a reality, the future is still far away.