1

SCHOOLS DEBATES 2012 NATIONAL TOPIC

Hydrogen, an energy carrier, is considered one of the most viable fuel alternatives to fossil fuels, but an

input of energy is required for its production. Solar energy is available in abundance on the African

continent. New research is developing nanotechnology to improve the harnessing of solar energy for the

production of hydrogen fuel. Do you think these developments in Hydrogen and Fuel Cell Technology will

offer Africa a viable solution for future sustainable energy?

Scientists and politicians have agreed that human activity and current methods of energy production have

placed tremendous strain on the environment. International conferences such as COP17 highlight the

importance of achieving ‘green’ methods of energy production The link between human activities,

increased greenhouse gas (GHG) emissions (such as carbon dioxide) and climate change was scientifically

confirmed and agreed internationally in 2007, and since then there has been intense focus on developing

renewable sources of energy that are clean (emit none or less greenhouse gas) than traditional coal and oil

based energy sources. One of the major developments was the use of hydrogen and fuel cells in the

alternative energy industry.

Hydrogen is the simplest element (remember its position on the periodic table?). Each atom of hydrogen

has only one proton. It's also the lightest element. At normal temperature and pressure it is a gas. At -

253°C (in other words very cold!) hydrogen condenses to a liquid. Apart from being the simplest element,

hydrogen is also the most plentiful gas in the universe. However, because hydrogen is so much lighter than

air, it rises very easily through the atmosphere. So it is rarely found as a gas floating around by itself on

Earth. However it does bind to other elements such as oxygen to make water (H2O). For our purposes

hydrogen’s most important property is that it can be used as an energy carrier. It stores energy derived

from a source and is able to transport and deliver it.

Fuel cells were invented about 150 years ago, and they convert chemical energy into electrical energy in a

clean, environmentally friendly way, with no harmful carbon dioxide (CO2) emissions. Electricity, heat and

water can be made by the reaction of hydrogen and oxygen with a fuel cell. Hydrogen can be produced

from any hydrocarbon compounds, including fossil fuels.

2

The South African government made a commitment in March 2011 to generate 42% of electricity from

renewable energy sources within the next 20 years. Given this commitment the emphasis in South Africa is

on producing energy from renewable energy sources in the long term. Fuel cell technology is more

efficient, reliable, quieter and more compact than most current electricity production methods (nuclear

energy is even more efficient). If the hydrogen used comes from a renewable source, such as solar energy,

this technology is also cleaner and better for the environment.

Nanotechnology is often called an ‘enabling’ or ‘refining’ technology as it allows existing technologies to be

improved. Since nanotechnology allows scientists to build nanometre-scale structures with molecular

precision (known as nanofabrication) from the ground up, molecules can be tailor-made for a specific

function. Nanotechnology offers a viable alternative to non-renewable fossil-fuel consumption and gives us

the means to achieve a “hydrogen economy”. Nano-applications in this area include: solar cells; fuel cells

and new energy production, conversion and storage processes. In all cases, the results are energy that is

cheaper, cleaner, more efficient and renewable.

Solar water-splitting is the process by which energy in solar photons are used to break down liquid water

into molecules of hydrogen and oxygen gas. Hydrogen produced through solar water-splitting is

sustainable and does not emit carbon into the atmosphere. This process is known as photoelectrochemical

splitting (‘photo’ meaning light).

Earlier this year a team of Californian scientists were able to make hydrogen gas by splitting it from water,

using sunlight trapped in nanowires. The scientists designed a nanowire forest of hundreds of nanowires

arranged in a 3D structure (see the image below). The nanowires trapped and reflected sunlight, and the

energy that they stored was used to split the hydrogen atom from the water molecule.

Figure 1. A nanowire forest used to trap solar energy. The image is magnified, but try to determine how

small the nano-structures are using the scale at the bottom of the picture.

Hydrogen is considered to be clean fuel compared to fossil fuel because there is no carbon emission, but

the hydrogen currently used is not generated cleanly. The benefit of the method described above is that no

greenhouse gases are released as a by-product. Solar energy then, is a very green way to make hydrogen

gas.

Utilitarian

There can be no doubt that with an ever increasing urbanised population, South Africa needs to invest

heavily in alternative energy. The recent power supply problems experienced by Eskom highlight this

problem. There is also no doubt that if we are going to invest in alternative energy, we should opt for

cleaner, greener, more sustainable sources. Nanotechnology is already playing a role in other areas of

3

product development. It is just as useful in the development of sustainable energy. Some of the major

advantages of using alternative energy are that it can be non-polluting and renewable. The use of

nanotechnology can improve the efficiency of alternative energy technologies. Nanoparticles are used to

improve the catalysts and membrane assemblies that are used in fuel cells. For example, platinum is used

as a catalyst for fuel cells. Nanoparticles are used in this process to reduce the amount of platinum needed.

Nanotechnology miniaturises the pores through which the ions pass in the fuel cell. A nanotechnologically

enhanced membrane can allow hydrogen ions to pass through the cell while blocking the flow of other

atoms or ions, such as oxygen. This allows more efficient membranes to be manufactured, making them

lighter and longer lasting. This, in turn, makes the resulting fuel cell smaller, lighter, more durable and less

expensive to produce.

Nanotechnology has also proven useful as a refining technology in solar energy. It is estimated that the

amount of energy that hits the earth every minute is enough to supply global energy needs for a week. So

theoretically, the world’s energy requirements for a whole year can be met by harnessing all the solar

energy that hits the earth in 52 minutes (which is only 10 minutes longer than an episode of Gossip Girl!).

Even though we can’t harness all the solar energy that hits the earth, we should try to harness as much

solar energy as possible in an economically efficient way. At present the efficiency of harnessing solar

energy has been recorded at a one time high of 43%, although the typical efficiency is usually between 11-

20%. At an efficiency of 20%, for every 100 watts of solar energy that hits a solar panel, it can produce 20

watts of power. Nanotechnology will be able to help in improving this efficiency and reducing the

economic cost. In 2009, a study conducted by Dr Rajesh Sharma and his colleagues at the University of

Arkansas in Little Rock in the USA developed a process involving nanostructures that showed great promise

in boosting the efficiency of titania photoanodes to use solar energy to generate hydrogen in fuel cells.

Socio-cultural

A major problem with energy sources today is that many of the oil rich nations are also the nations most

prone to war and civil unrest. There is thus a very real link between the price we pay for petrol in South

Africa and the civil unrest in Libya for example. Using alternative energy solutions and nanotechnology

offers the potential to reduce the impact of fluctuating world’s oil prices caused by political unrest. Also, by

allowing for local areas to cater for their own energy needs based on what is available (for example in

South Africa, people nearer a water source would benefit from hydropower, whilst solar power might be

better for areas like Oudtshoorn), energy sources can be decentralised. This means that more jobs can be

created in local economies and disruptions to large groups of people can be prevented. This is as true

about oil as it is about coal power.

Furthermore, both oil and coal reserves will someday soon be depleted leaving us with a much bigger

problem and perhaps no options other than turning to alternatives. By using this model, South Africa could

break its over-reliance on a single energy supplier (Eskom), which has not been able to meet all current

demands for electricity, and begin to rely on locally generated power. Every major town and city could thus

be responsible for its own energy needs. Alternatively, the energy generated locally can be fed into the

national electricity grid (Eskom) to supplement supply nationally. How does nanotechnology fit into this

picture? The more efficient you can make the alternative energy sources (as nanotechnology seeks to do),

the better these decentralised power stations can be. This means a greater energy supply to a larger

number of people, hopefully at a reduced cost. With nanotechnology being used in a hydrogen fuel cell

that uses solar radiation as a source of energy, the amount of energy produced can be increased quite

dramatically. People would be able to create a whole new industry from this type of technology and so

increase their livelihood while improving their quality of life and saving the environment. By using solar

energy as a means of making hydrogen we are able to decrease the amount of greenhouse gas that is

released into our atmosphere, which can only be a good thing.

4

Economic

One of the biggest reasons why the implementation of alternative energy is hindered is the expense of

many of the forms of alternative energy. For example, a new wind farm that is to be erected just outside

Grahamstown in the Eastern Cape is reportedly going to cost R200 million. Other forms of alternative

energy also come with pretty high price tags. The question that needs to be asked is whether, in the long

run, the benefits we stand to reap by lessening the burden on the environment will be worth it? Solar

energy for example typically requires four to five years of expensive energy before production costs are

recovered and systems begin paying for themselves. With nanotechnology however, tiny solar cells can be

printed onto very thin, flexible light-retaining materials, known as thin-film photovoltaic (TFPV) systems.

Silicon panels are fragile, bulky, heavy, and expensive. Thin-film modules are less expensive to manufacture

and use; they are flexible, light weight, and do not require expensive silicon, reducing the overall cost of

the technology itself. With nanotechnology, the time it will take consumers to recover production and

installation costs may be reduced since nanotechnology provides more light-collecting capabilities. Since,

as discussed earlier, the cost of production has been reduced, it is not unrealistic to say that

nanotechnology would be able to reduce the cost of alternative energy, whilst yielding a greater overall

benefit.

In terms of hydrogen fuel cells, Platinum Group Metals (PGMs) are the key catalytic materials used in most

fuel cells, and with more than 75% of the world’s known platinum reserves found in South Africa there is

great potential for economic benefits. Imagine, for example, if South Africa can start producing its own fuel

cells. South Africa’s platinum mines will be able to produce their own electricity and also sell the unused

electricity to the electricity grid, such as that of Eskom. Platinum mines could potentially become self-

sustaining in terms of their energy production, saving enormous amounts of money. The use of

nanotechnology can reduce the cost of energy production, distribution and storage, since it has the

advantage of reducing the amount of materials used without compromising the expected power outputs.

Use of solar energy would require a substantial capital outlay but, by applying nanotechnology, the amount

of sunlight absorbed by solar panels can be increased significantly, giving you more ‘bang for your buck’.

Furthermore, since the solar energy would be used to generate hydrogen for fuel cells, the economic

benefit is extended to more than just saving electricity. There are many uses for hydrogen fuel, for

example hydrogen powered cars, allowing us to save more money in the long run.

Advancement of Science

Through miniaturisation, nanotechnology also provides an opportunity to tailor-make solutions. In South

Africa, the interest in hydrogen and fuel cells forms part of the Hydrogen South Africa’s (HySA) strategic

objectives. HySA aims to position the country to drive and optimise the use of local natural resources to

produce fuel cells from supplying value-added products such PGMs to the potentially increasing global

markets. Furthermore, one of the well-reasoned and well tested aspects of capitalist competition would

lead to the exponential increase in research and development in the area of nanotechnology and

alternative energy: quite simply, if the market for these emerging technologies becomes big enough and

attractive enough for investors (who are always looking to invest in something that will pay them back one

day), the competition to produce better technology would propel the science in leaps and bounds.

Using solar energy to create hydrogen also allows for the advancement of hydrogen technology in general.

If the means of generating hydrogen become cleaner and more sustainable (as is the case when solar and

nanotechnology are used) then the only limit to the use of hydrogen energy would be our own

imaginations. The switch from a fuel to a hydrogen economy would bring with it ample opportunity for

greater technological ingenuity.

5

Democratisation of Science

Quite apart from advancing the science in the international arena, there is great potential for capitalising

on the spread of nanotechnology-enhanced alternative energy solutions as a way to educate the South

African population about various technologies and the benefit that they offer. A prime example of this is

the A hi fambeni (which in Tsonga means “let’s go!”) hydrogen powered tricycle which was unveiled by

Minister of Science and Technology, Naledi Pandor, at a technology and innovation conference in early

August 2010. According to Minister Pandor, “A hi fambeni offers a practical way to promote public

awareness of hydrogen and fuel cell technology as a clean energy alternative”. The bike was developed by

students of the Tshwane University of Technology in partnership with the Department of Science and

Technology and Hydrogen SA (who developed the hydrogen storage capability), proving that innovative

solutions that can be created when key groups work together. You may be wondering how popular this e-

bike (short for electric bike) will be (remembering this is meant for demonstrations). In China there were

only 400 000 e-bikes in use in 1998. By 2007 there were over 21 million e-bikes in use! In 2007 the

Department of Science and Technology launched Shova Kalula, which means “pedal easily” in isiZulu. This

is a partnership with the private sector and civil society that plans to give 1-million bicycles to school

children by 2015 and to build dedicated bicycle paths across the country. Minister Pandor stated that she

hopes a partnership can develop between the creators of A hi fambeni and Shova Kalula. This would be

another fantastic way of educating school children about hydrogen and fuel cell technology,

nanotechnology and other emerging technologies.

Conclusion

There are many ways in which nanotechnology is already in use in our everyday lives. Could it prove useful

as a means of making alternative energy solutions more viable? Are we willing to shoulder the economic

cost? Will it really provide a positive impact on the lives of ordinary South Africans?

Consider what you have read above and research the topic further. The answers are yours for the finding.

Good luck!

Compiled by The Collective Genius