Frequently Asked Questions
What’s the problem?
All nations across the globe face a severe energy crisis. Our current energy systems are based on fossil fuels, which not only have adverse effects on the environment, but are also depleted and running out. With the growing demand for energy predicted to increase by more than 50% by 2025 due to the rising world population, pressure is mounting to find alternative, renewable sources of energy.
The energy crisis is becoming more visible every day. At the political level, tensions continue to rise over access to oil as demand increases. The increasing cost of oil and other fossil fuels also impacts each of us on a daily basis with the cost of groceries and other basic goods escalating.
What energy system are we currently using?
The current economy implemented around the world is based on the burning of fossil fuels, including coal, oil and natural gas. When fossil fuels are burned, they release carbon dioxide (CO2), as well as many other toxic Greenhouse Gases (GHG) and particulates, which trap heat close to the earth’s surface instead of allowing it to radiate out to space. Emissions of GHG, which also include water vapour, methane and nitrous oxide, have grown signifi cantly since pre-industrial times, with an increase of 70% between 1970 and 2004. These increased emissions have caused the temperature of the earth to rise, an effect known as global warming. In 2007, scientists from collaborating nations around the world fi nally confi rmed the link between human activity, increased GHG emissions and climate change.
Reducing reliance on fossil fuels and replacing them with renewable energy sources is a priority across the globe, and countries are implementing policy and research to develop suitable alternatives.
What is the Hydrogen Economy?
The Hydrogen Economy is one option to develop an energy system based on safe, clean and reliable alternative energy sources – by using hydrogen to store and deliver energy. The term “Hydrogen Economy” was coined by John Bockris in 1970 during a talk at General Motors. Within this economy, hydrogen gas is the universal carrier of energy and links all sources of energy production with all points of energy consumption. If only renewable sources of energy are used, there are no net emissions of CO2 resulting from this system.
History has seen many new technologies and inventions that were initially expensive become more affordable, as the underlying markets matured and advanced Research and Development (R&D) resulted in increased efficiencies and productivities. It is likely that this will also be the case for using hydrogen, which will become more viable as the benefits, especially for the environment and human health, are seen against the negative impacts of the current system, which is based on limited natural resources. Within this proposed system based on hydrogen, Hydrogen and Fuel Cell Technologies (HFCT) are potential solutions for the 21st century and will enable both power and heat to be produced cleanly and efficiently from alternative sources of energy.
What is hydrogen?
Hydrogen is the most abundant element in the universe. Hydrogen itself is not an energy source – it is an energy carrier. It can store and move energy in a usable form from one place to another. Hydrogen can be produced by converting fossil fuels, or using energy from renewable sources such as wind, solar or biomass.
- The lightest gas and much lighter than air.
- A substance with no colour, smell or taste.
- A gas at normal temperature and pressure and condenses from a gas to a liquid at a temperature of -253˚C.
- The first element in the periodic table of chemical elements.
- The most abundant element in the universe, comprising some 90% of all atoms.
- A major constituent of the sun which is a giant ball made up of mostly hydrogen and helium.
- One of the most reactive substances in the world and highly flammable.
- One of the most reactive substances in the world and highly flammable.
Where is hydrogen found?
Although hydrogen is the most plentiful element in the universe, it is rarely found alone in nature because it tends to form compounds with other elements. For example, it joins with oxygen to form water (H2O). Separating the hydrogen from these compounds is one of the challenges of using hydrogen as an energy carrier.
One of the most common current methods to produce hydrogen uses steam to separate it from hydrocarbons found in petroleum and natural gas – a process which still emits CO2. A longer term option to produce hydrogen will be to extract it from water, a process known as “water splitting”. This process uses either heat (thermolysis) or electricity (electrolysis) to separate out the hydrogen from the oxygen in water – both methods can directly
use renewable energy sources.
Once hydrogen has been produced or extracted the energy it stores is transportable. This energy can be converted into electricity or heat as needed at the point of use through using a device such as a fuel cell.
What is a fuel cell?
Fuel cells convert chemical energy into electrical energy (electricity), using hydrogen or other fuels and oxygen from the surrounding air. In simple terms, a fuel cell operates like a “battery”, except that it does not run down or need electrical recharging. Hydrogen Fuel Cells (HFC) use a quiet, efficient process that can be repeated over and over, and converts the hydrogen’s energy to electricity, with heat and pure water as the only emissions.
Fuel cells were invented about 150 years ago by Welshman William Grove and they work by reverse electrolysis. Instead of splitting water molecules into hydrogen and oxygen, fuel cells combine hydrogen and oxygen to form water to release the energy content.
The three basic elements of a fuel cell are the catalyst-containing anode and cathode, and the electrolyte.
How does a hydrogen fuel cell work?
A fuel cell consists of three segments sandwiched together: the anode, the electrolyte (which is a membrane in the most common fuel cell type), and the cathode. The anode and cathode are coated with catalytic material, causing two chemical reactions to happen at the interfaces between the three segments. Hydrogen gas and oxygen (in air) are introduced to opposite sides of the separating membrane. As the hydrogen enters the fuel cell, the catalyst on the anode breaks down the hydrogen molecule into protons (H+) and electrons (e-). The protons (carrying a positive charge)
released are able to pass through the membrane to the oxygen on the other side. The membrane does not allow the electrons (that carry a negative charge) through, and instead they flow through an external circuit thereby creating an electrical current that can be used as a source of power. The catalyst at the cathode combines the protons with oxygen to form water.
HFC are usually named according to the electrolyte used, such as the Proton Exchange Membrane (PEM) and can be a variety of sizes. Since individually they produce a very low voltage (about ± 0.7 volts), they are usually “stacked” and connected in a series, one on top of another to increase the power output. The energy efficiency of a complete fuel cell system is generally between 40-60%, and can be up to 85% if waste heat is captured for use.
What are the uses of hydrogen fuel cells?
HFC can potentially be tailored for use wherever needed, for stationary and portable uses as well as in transportation, and applications range from powering cell phones to cars and houses and even entire neighbourhoods. They are especially useful in remote locations, such as for remote weather stations, nature reserves, military operations or even in submarines and space craft. HFC have the potential to replace the internal combustion engine in vehicles, and could radically change transportation.
Around the world, fuel cells are being developed for:
- Car and buses.
- Motorbikes, scooters and bicycles.
- Utility vehicles (e.g. forklift trucks, golf carts and tractors).
- Boats and submersibles.
- Combined heat and power (CHP) domestic and commercial energy needs.
- Back-up power, including Uninterrupted Power Supply (UPS) technology.
- Portable power (to replace power in portable electronic devices such as cell phones and laptop computers).
- Off grid power supply.
- Base load power plants.
What is happening in South Africa in hydrogen fuel cell technology?
Countries around the world have different motivations for investing in R&D in the area of HFCT. For example, Canada is investigating HFCT related to environmental protection and the United States of America is doing likewise, but for reasons of energy security. Japan plans to offer domestic fuel cells commercially soon and aims for a quarter of all Japanese homes to be powered by fuel cells by 2020. Some more advanced countries are also building up hydrogen fuelling infrastructure for hydrogen powered vehicles.
The South African government is driving the R&D on HFCT and related technologies for three main reasons:
- South Africa has an abundance of Platinum Group Metals (PGM), which are the key catalytic materials used in most fuel cells. This provides great potential for socio-economic benefits to be obtained from these natural resources due to the increased global demand for PGM products.
- The Human Capital Development (HCD) required to develop this sector will lead to job creation in South Africa – in order to supply the rest of the world with a much needed resource.
- R&D of HFCT as a viable alternative, renewable energy source is essential to reduce CO2 and GHG emissions and help meet the country’s commitment to the global targets.
What is Hydrogen South Africa?
Considered as a “frontier science and technology” platform, the Hydrogen and Fuel Cell Technologies Research, Development and Innovation Strategy was approved by the Department of Science and Technology (DST) in May 2007. Branded as Hydrogen South Africa (HySA) in 2008, the strategy stimulates and guides innovation along the value chain of HFCT in South Africa. A budget of R400 million was allocated to HySA by DST in the launch period between 2007 and 2011, and the timeline of the programme is 15 years. The ultimate goal of HySA is to facilitate the establishment of a South African HFCT industry that captures a signifi cant share of the global market. The ambitious national target is to supply 25% of the PGM content in the form of value-added products to the international fuel cell markets by 2020.
What are Platinum Group Metals?
PGMs are the key catalytic materials used in PEM fuel cells. The platinum catalyst is vital because it causes the atoms of hydrogen gas to break down into protons and electrons, releasing the energy it contains. One of the main motivators for South Africa’s investment into R&D of HFCT is because over 75% of the world’s platinum reserves are found in South Africa. Other facts about PGM:
- PGMs include platinum, iridium, osmium, palladium, rhodium and ruthenium – and all of these play important roles in PEM technologies.
- PGMs are renowned for their catalytic qualities and are also resistant to corrosion, chemically inert and have high melting points, making them useful in a number of applications.
- PGMs are predominantly mined in an area called the Bushveld Complex, discovered in the north of South Africa in 1897.
- The Bushveld Complex, which is a two billion year old igneous intrusion, contains some of the richest ore deposits on earth, including PGMs, tin, iron, titanium and chromium.
- South Africa’s platinum mines are found mainly in the North-West, Limpopo and Mpumalanga Provinces.
Who is working on hydrogen fuel cells?
As with any new technology, people with relevant qualifications and expertise are needed. To accelerate the development of this technology over the next two decades, high-end South African post graduates with relevant degrees in Science and Engineering need to be recruited to the sector. Developing the required human skills and expertise at various levels, more formally known as Human Capacity Development (HCD), is essential to the sustainable growth of the sector.
HySA is promoting collaborative and inter-disciplinary research and is developing a creative research training environment that is world class and internationally competitive. Increasing the number of South African students in the postgraduate pipeline, ranging from MSc to post-doctoral level is being tackled through the HySA HCD programme. Workshops, seminars, short courses and training manuals are being developed to promote learning of critical and basic scientifi c skills and knowledge related to HFCT as well as project management, basic leadership and relevant financial management where appropriate.
Both short and long-term exchange programmes and visits from world-renowned experts, and other international and national linkages are promoting knowledge transfer and mutual information exchange, and exposure to cutting edge research and alternative research and education systems. National internships and mentor programmes are also a part of this process.
What are the advantages of hydrogen fuel cells?
- Low to zero emissions – When hydrogen produced from clean technologies (“green” hydrogen) is used in fuel cells, there is zero pollution.
- Reliability – HFC are very reliable which is essential when high quality, uninterrupted power supply is needed.
- Quiet – Fuel cells operate silently, mainly due to the lack of moving parts, which also minimizes maintenance and operating costs.
- Efficient – Fuel cells are highly efficient at converting fuel to electrical energy, when compared to other electrical generating technology.
- Flexible – Not only can HFC be used for a variety of applications, they can also operate on a wide load range and scale from micro production to megawatt production.
What are the challenges of hydrogen fuel cell technology?
A lot of research is needed before fuel cells will become a practical alternative to current energy production methods – and it could be several decades before a hydrogen fuel cell-based energy system is a viable alternative. Some of the key challenges in this process are:
- High cost – The current high cost of producing fuel cells and related components will need to be reduced considerably if this technology is to be competitive. Although fuel cells will become more affordable when they are mass produced, the cost of the catalyst (i.e. the amount of platinum), also needs to be reduced.
- Storage and distribution – The low volumetric energy density of hydrogen gas requires new storage and distribution strategies, especially for use in cars i.e. a hydrogen storage tank for a hydrogen fuel cell vehicle, even at high pressures will be three times the size of an equivalent petrol tank. The availability of hydrogen is another key challenge which needs to be resolved before the technology can be scaled up and
commercialised, i.e. refuelling of cars.
- Durability – Fuel cell powered systems in cars will need to achieve the same level of durability as current automotive engines.
- Safety – As for all fuels, hydrogen is potentially dangerous and is flammable if not handled properly. However, unlike gasoline or natural gas, cars powered by hydrogen would not burn during a collision as the hydrogen quickly evaporates into the air.
- Industry linkages – Additional links are needed with industrial manufacturers in South Africa that are interested in getting involved in the future development of HFCT and the related business opportunities. These industries need to work closely with the researchers to find innovative ways of producing cost effective components and fuel cell systems.