Hydrogen Civilization
Tauhid Nur Azhar
I still vividly remember around mid-2020 when the Covid-19 pandemic was raging fiercely. I received a task from Prof. Hammam Riza, who at that time served as the Head of the Agency for the Assessment and Application of Technology of the Republic of Indonesia, to supervise the testing process of ventilator devices created by national engineers, supported by several strategic industries, including LEN.
It was in that ventilator team that I first met Prof. Eniya online, fully Prof. Dr. Eng. Eniya Listiani Dewi, one of Indonesia’s leading female scientists who is an alumnus of Waseda University in Japan, the same alma mater as the mathematics celebgram Jerome Polin.
Her official position at that time was Deputy Head of BPPT for Information Technology, Energy, and Materials. Currently, she has been entrusted with a heavy task that aligns with her personal passion, the Director General of New and Renewable Energy and Energy Conservation, or EBTKE, at the Ministry of Energy and Mineral Resources of the Republic of Indonesia.
Why do I say it aligns with her passion? Because she is one of the engineers and researchers who is very consistent in the development of new hydrogen-based energy. Various innovations from her research have been widely published, and I have even seen a prototype of a two-wheeled hydrogen vehicle of her creation, gleaming in the Puspiptek Serpong area.
Although her position at that time was Deputy or echelon I at BPPT, in the Covid task force, she was part of the ventilator development team. Her leadership quality was tested there; she was able to orchestrate many elements from various institutions with very heterogeneous characteristics very well. Synergy occurred, the coordination process, even with health institutions where pre-clinical ventilator tests were conducted in various cities and could only be contacted online, ran very smoothly.
That brief online introduction left a deep impression on me, to the point where I suddenly felt motivated to learn more about hydrogen. Perhaps dreams can be contagious, right?
A dream of a world where the sky is clear blue, the air is fresh, and vehicles run without leaving a trail of carbon emissions. This dream is getting closer to reality with the rapid development of new and renewable energy technology (EBT). Among the many innovations, hydrogen emerges as a star, promising a clean and sustainable future.
Hydrogen, the lightest and most abundant element in the universe, holds extraordinary potential as an energy source. Compared to fossil fuels, hydrogen is much more environmentally friendly. The combustion of hydrogen only produces water (H2O), without greenhouse gas emissions that harm the climate.
On the other hand, I am also well acquainted with Prof. Bambang Riyanto, an AI expert from STEI ITB. One of his team’s works is an autonomous tram developed in collaboration with INKA Madiun. In addition to adopting advanced control technology based on LiDAR, cameras, and various sensors, this autonomous tram is electrically powered, currently sourced from DC batteries.
The INKA ITB autonomous tram is the result of research funded by LPDP with the research title: Development of Autonomous Systems Using Artificial Intelligence for Trams. According to Prof. Bambang Riyanto, this innovation develops two main AI systems for the tram’s autonomous system, namely Tram Driving Assistance and Full Autonomous Tram. Both allow the tram to run on tram tracks that blend with other vehicles and pedestrians on the road, commonly known as mixed-traffic conditions, safely and comfortably.
This autonomous tram can avoid obstacles, maintain speed according to limits, and recognize traffic signs. Features such as Adaptive Cruise Control and Emergency Braking System are also installed to prevent collisions with other vehicles or pedestrians.
Because this autonomous tram is designed to operate automatically in a mixed traffic environment, various sensors such as cameras, radar, LiDAR, and GNSS are installed to detect objects around it, both in clear and rainy weather conditions. The data-information captured by these sensors is processed by artificial intelligence through embedded computing devices, allowing the tram to make decisions independently. This autonomous tram is powered by an electric motor supported by a 200 kWh battery, capable of traveling up to 90 km on a single charge.
From listening to Prof. BR’s discussion, as many of his students call him, in the KORIKA (Collaboration of Research and Artificial Intelligence Industry) group, it appears that the reliability of the INKA-ITB autonomous tram’s control system has been tested, and it can run well by prioritizing safety and security aspects in mixed vehicle traffic in the city of Solo. Tests were conducted on the train track usually traversed by the Sepur Kluthuk Jaladara tourist steam train and the regular commuter train on the Wonongiri-Purwosari route, KRDE Batara Kresna.
I imagine if the next generation or version 2.0 of the autonomous tram is a hydrogen-fueled tram with an electric motor powered by a fuel cell, how beautiful that emission-free and energy-efficient mode of transportation would be when it operates in cities or suburban areas, or even intercity and inter-province throughout the country.
The dream of a habitat that is part of a circular ecosystem driven by new and renewable energy seems not to be a utopia.
Perhaps in the next 2 or 3 decades, we will see more cities and suburban satellite areas powered entirely by new and renewable energy. Solar power plants, micro-hydro, hydrogen, and even nuclear fusion integrated with the grid system to power public transportation systems, public service facilities, data connectivity, integrated smart agriculture, livestock and fisheries with a smart agro-mining concept, as well as maintenance, fertilization, and drip irrigation of city parks and forests, and residential electricity needs and waste processing with a sustainable concept.
Pedestrian areas and floors of all public facilities can be equipped with piezoelectric tiles. The conversion of pedestrians’ kinetic energy using piezoelectric technology can generate electricity when someone steps on a tile, which will bend and press an electromagnetic generator underneath. The rotation of this electromagnetic generator will produce electricity.
Integrated agriculture will be monitored and managed by an AI-based automated system. Nutrient liquids, temperature and humidity, drip irrigation and spray, and light intensity settings will all be controlled by a system equipped with sensors and various IoT devices. All analyzed and driven by AI. Similarly, the fisheries and livestock systems and the nano-nutrition industry, all are already operating independently and can anticipate and predict dynamic situations and fluctuating conditions.
All of this can happen if we focus on developing a hydrogen-based power system. Why? Because as a water planet with a liquid phase dominance of 71%, of which 96.5% is in the oceans, the water resources that can be converted into hydrogen are vast, right?
The process of harvesting hydrogen from water can be done by applying chemical-physical technology known as electrolysis. Water electrolysis is the process of splitting water molecules (H₂O) into hydrogen gas (H₂) and oxygen gas (O₂) using direct current (DC) electricity. This process occurs in an electrolysis cell consisting of two electrodes, a cathode (negative electrode) and an anode (positive electrode), immersed in water to which an electrolyte has been added to increase its conductivity.
The basic principle is the Reduction Reaction at the Cathode, where water (H₂O) is reduced by receiving electrons (e⁻) from the power source, producing hydrogen gas (H₂) and hydroxide ions (OH⁻): 2H₂O(l) + 2e⁻ → H₂(g) + 2OH⁻(aq)
The Oxidation Reaction at the Anode, where water (H₂O) is oxidized by releasing electrons (e⁻) to the power source, producing oxygen gas (O₂) and hydrogen ions (H⁺): 2H₂O(l) → O₂(g) + 4H⁺(aq) + 4e⁻
The Overall Reaction, by combining the two half-reactions above, the overall reaction of water electrolysis is obtained: 2H₂O(l) → 2H₂(g) + O₂(g)
The components of the Electrolysis Cell include: Electrodes, common electrode materials are platinum, nickel, or stainless steel. The choice of electrode material affects the efficiency and cost of the process. Electrolyte, electrolyte is added to the water to increase its conductivity, allowing electric current to flow more easily. Commonly used electrolytes are sulfuric acid (H₂SO₄), potassium hydroxide (KOH), or sodium hydroxide (NaOH). Power Source, a DC power source that provides the electrical energy needed to drive the electrolysis reaction. Ideally, the power source comes from renewable energy such as solar or wind to produce green hydrogen. Diaphragm/Membrane, a diaphragm or membrane is used to separate the produced hydrogen and oxygen gases, preventing a reverse reaction and explosion.
Factors affecting the efficiency of the water electrolysis process include: Type of Electrode: electrode material affects overpotential, the additional voltage required to initiate the electrolysis reaction. Electrolyte Concentration: optimal electrolyte concentration can increase the solution’s conductivity and process efficiency. Temperature: increasing the temperature can increase the rate of the electrolysis reaction. Inter-Electrode Distance: a closer inter-electrode distance can reduce resistance and increase efficiency. Current Density: optimal current density can increase the rate of hydrogen production.
The advantage of water electrolysis is its environmentally friendly nature, especially if using electricity from renewable sources; water electrolysis can produce “green” hydrogen without carbon emissions.
Another benefit is the high purity of the hydrogen gas produced, suitable for various applications. Electrolysis technology can also be applied on a small or large scale, according to needs, flexible and adaptive to the conditions faced.
In addition to water electrolysis, hydrogen can also be obtained from recycling organic waste or biomass, thus strengthening its circular nature, right? The process of treating organic waste or biomass relies on the presence of its methane gas (CH4). This process is called Steam Methane Reforming or SMR.
Steam Methane Reforming (SMR) is the most commonly used process for commercially producing hydrogen. This process involves a reaction between methane (CH₄), the main component of natural gas, and steam (H₂O) at high temperatures (700–1000°C) and moderate pressures (15–30 bar) with the help of a catalyst.
The main reaction in SMR is endothermic, meaning it requires heat to proceed: CH₄(g) + H₂O(g) ⇌ CO(g) + 3H₂(g) ΔH = +206 kJ/mol
Methane reacts with steam, producing carbon monoxide gas (CO) and hydrogen gas (H₂). This reaction is reversible, meaning it can proceed in both directions.
SMR is generally carried out in two main stages: Reforming: A mixture of methane and steam is passed through reformer tubes containing a nickel catalyst. At high temperature and pressure, the reforming reaction occurs, producing syngas containing hydrogen, carbon monoxide, and a small amount of carbon dioxide. Water-Gas Shift Reaction (WGSR): The syngas from the reformer is then passed through a WGSR reactor. Here, carbon monoxide reacts with steam to produce more hydrogen and carbon dioxide: CO(g) + H₂O(g) ⇌ CO₂(g) + H₂(g) ΔH = -41 kJ/mol
WGSR is exothermic, releasing heat. This reaction is usually carried out in two stages, high-temperature WGSR (350–450°C) and low-temperature WGSR (200–250°C) with different catalysts to maximize the conversion of CO to CO₂ and H₂.
Catalysts play a crucial role in SMR to accelerate the reaction rate and increase efficiency. Commonly used catalysts are nickel supported on alumina or other support materials. These catalysts can be deactivated by carbon deposition (coking) or sulfur poisoning, requiring periodic regeneration or replacement.
Factors affecting reaction efficiency include: Temperature and Pressure: Optimal operating temperature and pressure must be maintained to maximize hydrogen production. Steam/Methane Ratio: The correct steam-to-methane ratio must be maintained to prevent carbon formation and increase efficiency. Catalyst Activity: The activity and selectivity of the catalyst significantly affect SMR efficiency. Gas Purification: After WGSR, the reaction gas must be purified to separate hydrogen from CO₂, CO, and other impurities. A commonly used purification method is pressure swing adsorption (PSA).
The advantages of SMR technology include: Mature Technology: SMR is a proven technology widely used commercially. Relatively Low Cost: Compared to other hydrogen production methods, SMR is relatively cheaper. Scalability: SMR can be applied on a small or large scale.
The disadvantage of SMR technology is the presence of carbon emissions since SMR produces CO₂ as a byproduct. However, carbon capture and storage (CCS) technology can be used to reduce emissions.
In the future, especially considering that Indonesia is located in the tropics with abundant sunlight and plants that can photosynthesize year-round, hydrogen-producing bioreactors could be an attractive option. And algae, especially microalgae, which are also starting to be used as CO2 and COx capturers from urban emissions (currently in the trial phase in one area of South Tangerang City), are one of the vegetation types with potential as a hydrogen source.
Algae, especially microalgae, meet the criteria as a potential source for sustainable hydrogen production. Microalgae can produce hydrogen through a process called bio-photolysis, which utilizes solar energy to split water into hydrogen and oxygen.
Here is a more detailed explanation of hydrogen production from algae: Bio-photolysis Mechanism Photosynthesis: Like plants, algae perform photosynthesis to produce energy. During photosynthesis, algae absorb solar energy and use it to convert water and carbon dioxide into carbohydrates and oxygen. Hydrogen Production: Under certain conditions, such as sulfur or oxygen deficiency, some types of algae can shift their metabolism to produce hydrogen. This process involves the enzyme hydrogenase, which catalyzes the reaction of splitting water into hydrogen and oxygen.
Several species of microalgae are known to have the capacity to produce hydrogen, including: Euastrum, Cosmarium, Chlorella sp., Ulothrix, Selenastrum, Chlamydomonas sp., Closterium, Micractinium sp., Pandorina, Stigeoclonium, and Staurastrum (Wang et al., 2020a, Wang et al., 2020b).
Some types of algae that have been studied for hydrogen production include: Chlamydomonas reinhardtii: A unicellular green alga widely used in bio-photolysis research. Scenedesmus obliquus: A green alga that can produce hydrogen under sulfur-deficient conditions. Chlorella vulgaris: A green alga that can also produce hydrogen, but with lower efficiency.
Factors affecting bio-hydrogen production from algae bioreactors include: Light Intensity: Optimal light intensity is required for photosynthesis and hydrogen production. Nutrient Conditions: Deficiency in certain nutrients, such as sulfur, can trigger hydrogen production. pH: The pH of the culture medium affects the activity of the hydrogenase enzyme. Temperature: Optimal temperature is required for algae growth and enzyme activity. Type and Concentration of Algae: The type and concentration of algae affect the efficiency of hydrogen production.
Bio-hydrogen Production Methods include: Open System: Algae are cultured in open ponds exposed to sunlight. This method is relatively cheap, but its efficiency is low due to fluctuations in environmental conditions. Closed System (Photobioreactor): Algae are cultured in photobioreactors that allow control of environmental parameters such as light intensity, temperature, and pH. This method is more efficient but has a higher investment cost.
The advantages of hydrogen production from algae include: Algae are a renewable resource that can be easily cultivated. Hydrogen production from algae does not produce carbon emissions. Algae can also be cultivated sustainably without depleting other natural resources.
Some challenges in developing bio-hydrogen from microalgae include the need to develop technology for producing hydrogen from algae on a large scale economically.
Currently, researchers are developing genetically engineered algae to increase the efficiency of hydrogen production.
It is also known that nanomaterials can be used to enhance electron transfer and the efficiency of photobioreactors.
Although still in the development stage, hydrogen production from algae has great potential to become a clean and sustainable energy source in the future.
Next, of course, after hydrogen can be produced in massive quantities, we will need technology to convert it into energy or electricity, right? One of the most efficient and environmentally friendly methods is the fuel cell method.
A fuel cell, or fuel cell, is an electrochemical device that converts the chemical energy of a fuel (usually hydrogen) and an oxidant (usually oxygen) directly into electrical energy. Unlike batteries that store energy, fuel cells produce electricity continuously as long as fuel and oxidant are supplied.
Here is a technical explanation of how a fuel cell works: Its main components include: Anode: The negative electrode where fuel (hydrogen) oxidation occurs. Cathode: The positive electrode where oxidant (oxygen) reduction occurs. Electrolyte: A material that conducts ions and separates the anode and cathode. The type of electrolyte varies depending on the type of fuel cell. Catalyst: A material that accelerates the reaction rate at the anode and cathode. Commonly used catalysts are platinum or platinum alloys.
The working principle of a fuel cell is roughly as follows: At the Anode: Hydrogen gas (H₂) is passed over the anode. With the help of a catalyst, hydrogen molecules are split into hydrogen ions (H⁺) and electrons (e⁻). 2H₂ → 4H⁺ + 4e⁻ In the Electrolyte: Hydrogen ions (H⁺) move through the electrolyte toward the cathode. The electrolyte only allows hydrogen ions to pass through, while electrons are blocked. At the Cathode: Oxygen gas (O₂) is passed over the cathode. Oxygen reacts with hydrogen ions (H⁺) and electrons (e⁻) coming from the anode, producing water (H₂O). O₂ + 4H⁺ + 4e⁻ → 2H₂O Electron Flow: Electrons released at the anode flow through an external circuit to the cathode, generating an electric current that can be used to power a load (such as an electric motor).
Types of Fuel Cells: There are several types of fuel cells differentiated by the type of electrolyte used, each with different characteristics and applications: Proton Exchange Membrane Fuel Cell (PEMFC): Uses a polymer membrane as the electrolyte. Operates at low temperatures (80–100°C), suitable for vehicles and portable applications. Alkaline Fuel Cell (AFC): Uses an alkaline solution (such as KOH) as the electrolyte. High efficiency, but sensitive to CO₂. Used in spacecraft. Solid Oxide Fuel Cell (SOFC): Uses a solid ceramic as the electrolyte. Operates at high temperatures (600–1000°C), suitable for stationary power generation. Molten Carbonate Fuel Cell (MCFC): Uses molten carbonate salt as the electrolyte. Operates at high temperatures (650°C), suitable for stationary power generation. Phosphoric Acid Fuel Cell (PAFC): Uses phosphoric acid as the electrolyte. Operates at medium temperatures (150–200°C), suitable for stationary power generation.
The advantages of fuel cells include having a higher energy conversion efficiency compared to internal combustion engines. Fuel cell emissions are also very low, producing only water (for hydrogen fuel cells). Fuel cells operate very quietly because there are no moving parts. Fuel cells can be made in various sizes, from small scales for electronic devices to large scales for power plants.
Therefore, there is great hope that if the hydrogen production and energy conversion process is successfully developed, we may be able to witness again an imaginary city as perhaps seen by Ptolemy, a Greek geographer who traveled as far as the southern hemisphere around 150 AD, who witnessed a city he called Argyre, or the Silver City. Records of that city at the western tip of Java Island are found in his book titled Geographia.
The future silver or metallic city can be envisioned as a city with smart autonomous technology controlling and driving all its public service systems. Powered by hydrogen-based renewable energy, this city has fully implemented the circular concept in every aspect of its functionality. Monitored by post-artificial general AI imitation intelligence, all its public service systems and infrastructure management and development are fully controlled by an integrated AI system.
Autonomous vehicles, UAVs, hospitals, nutrition industry, educational media, and many other things operate independently with a level of precision beyond our current imagination.
