Electric or Hydrogen? Both sound like exemplary options, however, looks can be deceiving. Electric vehicles are vehicles that use electric motors as a source of propulsion, while hydrogen-powered vehicles use a fuel cell that uses hydrogen and oxygen molecules which react and form electricity. This electricity is used to run the electric motors. While both hydrogen and electric-powered cars have little to no local carbon emissions, they still have some cons that overshadow them.
According to the US Environmental Protection Agency (2017) report, transportation accounted for the highest amount of carbon emissions contributing to climate change. Agriculture was said to produce 9% of carbon emissions, commercial and residential owned 12% of carbon emissions, Industry possess 22% of carbon emissions, Electricity occupies 28% of carbon emissions and Transportation accounts for a devastating 29% of carbon emissions. (David Keith and Christopher R. Knittel 2019)
I am writing this essay as I am looking for ways for us (as humans) as we need to find other alternatives of energy sources to fuel our vehicles as our carbon footprint is damaging the environment. I believe that we as a global community can change our mistakes by using renewable energy resources. Would we want to get rid of our vehicles just to help reduce our carbon footprint? No, right? We can change, and this movement by starting by replacing fossil-fuelled cars with electric and hydrogen-powered vehicles.
Now let us look at the benefits of electric cars over hydrogen-powered cars: They are better for the environment as EVs have zero exhaust emissions, They use renewable sources of energy such as solar power which helps to reduce the carbon footprint on the environment. EVs are manufactured using eco-friendly materials which help to improve the environment and make it cleaner. They create health benefits, as there is a reduction in the emission of harmful exhaust gases, furthermore, EVs are less noisy thus there is less noise pollution. Moreover, EVs are cheaper to maintain as they have minimum moving parts such as fuel injection, radiators, exhaust systems etc.
In recent studies, by Ergon Energy (2019), several EV features have shown that they can improve safety further. These features include having a lower centre of gravity making it less likely to roll over, there’s a lower risk of fires and explosions and EVs are made of durable materials that make them safer in collisions. (Anon., 2019)
According to FutureofWorking (2019), Hydrogen fuel cells also have numerous pros that make them a sustainable energy source.
- They offer an effective energy, when energy is stored in the form of hydrogen in liquid or gas form, it will not dissipate.
- They offer high energy efficiency. According to the Connecticut Hydrogen-Fuel Cell Coalition, when a fuel cell is used with heating and power systems, efficiency surpasses 80%
- Carbon emissions of hydrogen fuel cells are zero as the products are water vapour and hot air. (Regoli, 2019)
However, the disadvantages of Electric and Hydrogen-powered cars cannot be overlooked:
In Chris Riley’s opinion, various problems affect EVs as a whole:
- Charging problems: Electric cars have to charge at charging stations, which may inconvenience people as they are generally placed in distant areas. Charging takes a long time to charge (about 3hrs), and also you have to carry the charging equipment along with you.
- Overpriced: Batteries used in electric cars are very expensive as the battery is made of Lithium-ion, which is a rare metal and can only be mined in a handful of countries. Consequently, batteries become expensive to produce and heavy.
- Pollute the environment: Yes, Electric cars pollute the environment but indirectly. The cars themselves are clean however the batteries they are carrying contain toxic elements which may produce harmful fumes. Furthermore, the electricity generated by stations is not powered by renewable energy resources thus the production of EVs produce a carbon dioxide which is harmful to the environment.
- Massive: Batteries in EVs are heavy, they weigh 1000 pounds (453.592kg). This causes the weight puts pressure on the battery causing them to drain faster. (Riley, 2019)
According to Green Garage, the hydrogen fuel cell is in itself has proven to be a disadvantage due to the following reasons:
- Expensive: Hydrogen is expensive as it takes a long time to separate hydrogen from other elements.
- Difficult to store: Hydrogen is extremely hard to move around thus transporting Hydrogen even in small amounts is very hard.
- Highly flammable: As a powerful source of energy, it is very flammable. It burns at large concentrations typical between 4%-75%.
- Dependant on Fossil fuels: Even as hydrogen is a renewable energy resource, it requires non-renewable resources (e.g. oil, coal etc) to separate it from oxygen.
- Hard to replace an existing infrastructure: This occurs as there isn’t an infrastructure that can support hydrogen as a fuel. (Sonalie Figueiras, 2015)
Based on the Pros and Cons of Electric and Hydrogen-powered cars above, Electric cars seem to have more advantages than disadvantages than Hydrogen-powered cars. But does that mean that they are better than Hydrogen-powered cars? According to Global EV Outlook 2019, in 2018 the global electric car fleet exceeded 5.1 million, which is 2 million more than in 2017. The Peoples Republic of China is the world’s largest electric car market, followed by Europe and the USA. Norway the leader in terms of electric car market share. Policies also play a very important role, as the leading countries in electric transportation use a variety of measures such as fuel economy standards tied with zero and low emission vehicles. Technological advances have brought about cost cuts, key enablers are developments in battery chemistry and the expansion of production capacity in manufacturing plants. The private sector response to public policy shows the widening market for electric vehicles. Battery manufacturing is also undergoing important transitions as well as big investment to expand production.
These developments portray a positive outlook on the deployment of electric cars and the charging infrastructure. It is projected that in 2030, that the EV stock will cut the demands for oil products by 127 million tonnes, while with more EVs in the EV30@30 Scenario the reduced oil demands are estimated to reach 4.3 million barrels per day. Electricity demand to power the EVs in the New Policies Scenario is projected at 640 TWh (terawatt-hours) while the EV30@30 Scenario has a projected demand of 1 110 TWh. Global EV Outlook 2019, has also projected that the sale of electric cars on a global scale will reach 23 million, with stocks surpassing 130 million. On a day-to-day basis, EVs will continue to reduce the carbon emission from internal combustion engines (ICE) vehicles. In the New Policies Scenario, the projected green-house gases emissions of the EV fleet will reach 230 million tonnes of carbon dioxide equivalent (Mt CO2-eq), offsetting an astounding 220 Mt CO2-eq emissions.
The EV and the battery production require large amounts of new materials in the automotive sector, thus causing an increasing attention to the raw materials supply. Traceability and transparency of raw materials can help reduce the problems brought about when supplying sustainable chains of raw materials. The increasing movement towards EVs may tamper with the tax revenue base that was gotten from vehicle and fuel tax. However, this issue can be solved by slowing increasing the tax on fuels that produce high amounts of carbon dioxide, along with distance-location based charges can foster the long-term transition to EV while maintaining tax revenues on transportation. (Global EV 2019)
Hydrogen is the simplest form of molecules; however, it has the highest energy content by weight. Substantial amount of research is being put in to create an efficient way for hydrogen to be used in transportation. According to the Hydrogen Fuel Cell Vehicles; Current Status and Future Prospect report (2019) Automotive companies such as Honda, Hyundai and Toyota have all started manufacturing fuel cell vehicles which use hydrogen as the source of fuel. According to the Combustion and Sustainable Energy Laboratory (ComSEL), Department of Mechanical Engineering, Arkansas Tech University, as of June 2018, there have been over 6500 FCVs sold to consumers. California is the leading market in FCVs with nearly 3000 delivered there out of 5233 being sold globally. This is because California has the largest hydrogen refuelling stations in the world and also due to car companies manufacturing vehicles there.
FCVs have above a 300-mile range and take less than 10 minutes to recharge at a hydrogen recharge station, it is estimated in 2030 that the cost of fuel cells will have competition with ICEs due to technological advancements and increased availability. One drawback of hydrogen is a means to store it efficiently as it can’t be stored the same way as fossil fuels, it has to be separated through cooling, compression or through both processes. The most favourable method to store hydrogen is in a physical containment such as compressed tanks. All composites (Type IV) are used primarily, or sometimes metal lined composites (Type III) are used. Once the hydrogen is pre-cooled, the fill time of these tanks is competitive with fossil fuels. Cost is another big setback for the wide-scale use of compressed hydrogen (CH2) tanks, as the material and assembly are expensive, furthermore, another potential setback is the public’s concern for using high pressure (70MPa) in storage tanks in vehicles. An alternative to CH2 tanks is still being researched; ideas such as internal skeleton, complex designs of struts intention to help withstand the pressure of the compressed gas. The storage of liquid hydrogen (LH2) has improved drastically, achieving the best specific mass (15%) of any other automotive hydrogen system. Even though hydrogen is in the atmosphere it is not in its purest form, hydrogen can be extracted from sources such as water, hydrocarbon fuel, hydrogen sulphide and other elements. The energy needed to produce hydrogen needs external energy such as thermal, electrical, photonic and biochemical energy.
Due to hydrogens low energy-density, it is hard to store enough on-board the vehicle to obtain an adequate driving-range without the container being heavy or large. Pressurised tanks are made with carbon-fibre cylinders that involve an impact resistance for safety in collisions. Compressed hydrogen in such tanks has an illustrated to have a 34MPa, with a mass of 32.5kg and the volume of 186L, which is adequate for a 500-km range; the tank volume is 90% of a 55-gallon drum which is large for a vehicle. (Yogesh Manoharan, 2019)
In the light of the situation, it is easy to see that Electric cars are much better compared to Hydrogen fuel cell, according to Zachary Shahan (2016) as most hydrogen produced today is from methane reforming. This destroys the purpose of using hydrogen cars as a solution to help improve the environment and climate change, as carbon monoxide and dioxide are by-products of the process. Moreover, hydrogen cars have to get their power from electricity, which is then converted into hydrogen and then back into electricity, it causes power losses of up to 45%. (Shahan, 2016)
- Anon., 2019. Benefits of electric vehicles. [Online] Available at: https://www.ergon.com.au/network/smarter-energy/electric-vehicles/benefits-of-electric-vehicles[Accessed 22 Oct 2019].
- IEA, 2019. Global EV Outlook 2019, IEA, Paris: IEA. Regoli, N., 2019. 18 Advantages and Disadvantages of Hydrogen Fuel Cells. [Online] Available at: https://futureofworking.com/10-advantages-and-disadvantages-of-hydrogen-fuel-cells/[Accessed 22 Oct 2019].
- Riley, C., 2019. Top 7 Disadvatanges of Electric Cars. [Online] Available at: https://autowise.com/top-7-disadvantages-of-electric-cars/[Accessed 22 Oct 2019].
- Shahan, Z., 2016. Why hydrogen fuel cell cars are not competitive — from a hydrogen fuel cell expert. [Online] Available at: https://energypost.eu/hydrogen-fuel-cell-cars-competitive-hydrogen-fuel-cell-expert/[Accessed 23 Oct 2019].
- Sonalie Figueiras, 2015. 11 Big Advantages and Disadvantages of Hydrogen Fuel Cells. [Online] Available at: https://greengarageblog.org/11-big-advantages-and-disadvantages-of-hydrogen-fuel-cells[Accessed 23 Oct 2019].
- Yogesh Manoharan, S. E. H. ,. B. B. H. A., 2019. Hydrogen Fuel Cell Vehicles; Current Status and Future Prospect, Arkansas: Combustion and Sustainable Energy Laboratory (ComSEL), Department of Mechanical Engineering, Arkansas Tech University.