Part - III
Wind is an important source of energy. There are about 200,000 wind turbines operating in the world, with the largest of about 75,000MW in China followed by USA (60,000MW), Germany (31,000MW), Spain (21,000MW) and India (19,000MW). The world’s electricity generation capacity from wind has been increasing rapidly (about 20 percent annually) with China racing ahead of others.
Electricity from wind turbines contributes to 28 percent of electricity production in Denmark, 19 percent in Portugal, 16 percent in Spain, 14 percent in Ireland and eight percent in Germany. A programme to generate electricity from wind on a large scale was begun in 2001 and the wind mapping of the country revealed that 20,000MW of electricity could be produced in the Sindh (Katti Bander-Gharo-Hyderabad region) and Balochistan coastal areas.
By now Pakistan could have been producing over 5,000MW of electricity. However, under subsequent governments the prices were negotiated upwards by corrupt government officials thereby driving away potential investors, and no significant progress could be made.
The sea can be a good choice for installing floating windmills since wind speed on the sea is greater than on land. Moreover floating windmills do not utilise valuable land that can be used for agriculture or other purposes. Hence, there is a strong case for building windmills a few miles away from the shore. Since the blades are quite heavy, they can make the structures top-heavy and unstable so that they can easily topple easily in rough weather. The challenge has, therefore, been to stabilise them so that they can operate safely under very rough sea conditions.
A consortium of US universities and companies, ‘DeepCwind’ was formed to address this problem. On June 13, under the Offshore Wind Accelerator Project (of the Clean Energy States Alliance) the first offshore floating wind turbine was inaugurated. It supplies electricity to the grid, thereby opening vast new vistas of energy production on the seas. A floating wind farm demonstrator project is also to be installed off the coast of Japan based on Statoil’s Hywind spar-buoy turbine. The Norwegian group is carrying out a feasibility study for the pioneering design which has been successfully produced in Norway since 2009.
About 75 percent of the universe is made up of hydrogen. Its fusion at high temperatures leads to the heat and light that warm and illuminate our planet. Hydrogen is, therefore, an obvious and excellent source of energy. This is apparent from the fact that the ‘energy density’ of hydrogen is almost four times that of kerosene.
Water could be a huge and cheap source of hydrogen if we could find some way to efficiently and economically cleave the hydrogen-oxygen bonds of the water molecule. Nature already does this very beautifully during the process of photosynthesis using certain enzymes. These enzymes are, however, not available on a large scale as they are unstable if they are removed from their natural environment. We have a large amount of sea water on our planet, and this could be a huge source of clean energy, since burning of hydrogen results in its reconversion back to water.
Scientists have been struggling to develop ways to cleave the hydrogen-oxygen bonds present in water in order to produce hydrogen. Certain metal catalysts such as platinum can do this but they are expensive. Now scientists at UC Berkley’s chemistry department have succeeded in developing a molybdenum catalyst that is 70 times cheaper, and may be used at the industrial level for hydrogen production. So cars are being developed that can use hydrogen as fuel, instead of petrol. Networks of hydrogen filling stations have been set up in USA, Europe and Japan, and the use of hydrogen to power car engines is growing rapidly. Many buses in Japan already run on hydrogen.
Nature is a great teacher and humankind continues to learn from it. Carrying out the photosynthetic process artificially in high yields and with good efficiency has been a golden grail in science for researchers. Can the common spinach that we eat dinner be a solution? Amazingly, the answer is yes! Now scientists at US Department of Energy's Oak Ridge National Laboratory (ORNL) in Tennessee have shown that the process of photosynthesis can be copied to produce hydrogen by the action of sun light on a membrane prepared from a spinach protein. Once the process is demonstrated to be commercially successful, you may one day drive a car on hydrogen derived using spinach.
One problem with hydrogen is its storage. Liquid hydrogen has to be stored at -253 degrees celsius, which is expensive and cumbersome for use in cars or other appliances. A British company Cella Energy has come forward with a new way in which hydrogen can be used. They have developed a hydrogen fuel using nanotechnology in which hydrogen is stored on microbeads as a hydride compound. It can be used in cars without any modification to the engines, and can be filled from normal petrol pumps.
The hydrogen has been developed as pellets and also in the form of a tissue. The cost to produce it is about $1.5 per gallon, making it cheaper than fossil fuels. The development of this exciting synthetic fuel is being kept a secret by the scientists at the Rutherford Appleton Laboratory near Oxford who were involved in its development.
Another new source of hydrogen is waste water. The water discharged from our toilets has a considerable amount of organic material in it. This can be decomposed using certain electrochemically active bacteria to produce hydrogen in excellent yields. The process is conducted in ‘microbial electrolysis cells’ (MECs), and the hydrogen produced from them can be burnt to generate electricity directly from waste water.
A small electrical input (0.2 volts) is needed in this process. This is met by extracting energy from the ionic differences between sea water and fresh water. So such processing plants need to be located near the sea side so that one has availability of large quantities of sea water. This exciting work was done by Bruce Logan and colleagues at the Hydrogen Energy Centre in Penn State University, and represents a process for waste water treatment that generates electricity from the hydrogen produced.
There is urgent need in Pakistan to utilise wind energy resources along with our coal, water, shale and methane resources. For this we need to have people with a vision and dynamism to execute projects within the next two years. It is hoped that the present government will not let time slip by, as our industry lies devastated by the power failures and high cost of energy.
The writer is the president of the Pakistan Academy of Sciences and former chairman of the HEC.Email: ibne_sina@hotmail.com
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