Shedding Light on Cheaper Solar EnergyWritten by Brenda Townsend Hall
Renewable sources of energy are key to solving two of worlds most pressing yet seemingly irreconcilable problems. On one hand developing world needs vastly to increase access to affordable energy because, at present, 1.6 billion people in world's poorest countries do not have a power supply. However, on other, we cannot go on depleting world's finite resources of fossil fuels and contributing to emission of harmful greenhouse gases by burning them. Thus sustainable development is threatened by a 'double whammy': difficulty of meeting increasing demands for energy, without which development aims cannot be met, and by environmentally harmful systems most often used to provide it.
Affordable, renewable energy sources would contribute greatly to breaking this impasse. However, field is a complex one and nobody believes a single solution will be found that can answer all world's energy needs. Even renewable sources have their drawbacks - wind and solar systems, for example, may never be able to stand alone as energy providers because they are, by their very nature, intermittent. However, they can be used very effectively in conjunction with other systems. A judicious mix of energy-producing systems can contribute to sustainable development by increasing availability of energy to poor, while reducing harmful impacts on environment. But an intransigent limiting factor is cost, particularly of conversion of sunlight for energy. If systems are not affordable they will be beyond reach of poorer countries whose needs are most pressing.
Recently, however, a project undertaken by a team of physicists, chemists, material scientists and engineers at Sheffield Hallam University, with funding from Engineering and Physical Sciences Research Council (EPSRC), has given a new boost to economic feasibility of solar energy. The research has shown how to reduce cost of generating solar electricity. Although electricity generation through interaction of sun's heat and light with semiconductors (called photovoltaics [PV]) has recognised environmental benefits, technology has hitherto been hampered by relatively high costs involved.
Now Sheffield Hallam University team has come up with some cost-cutting ideas: a low-cost semiconductor production method called electrodeposition, less reliance on expensive semiconductor materials, and identification of alternative solar cell devices and manufacturing techniques with higher conversion efficiencies. Such efficiencies mean that more power can be produced per cell so that cost of each unit of electricity generated is reduced.
Evolution of matterWritten by Vadim Smolyanov and Valentina Smolyanova
© 2003 Vadim Smolyanov and Valentina Smolyanova
Translated from Russian. We shall be glad to receive your remarks on stylistics, grammar, and content.
Chapter I. Evolution of lifeless matter
We more likely fortunately than unfortunately are in world where there is a time-space and a matter where a duality, variety and constant changes exist. But how to manage to describe World or its any phenomenon if you being in it? The most interesting phenomenon known to a science is Great explosion, a birth of universe which was about 15-20 billion years ago. What had become reason of it? The condition of universe before birth cannot be transferred by words means. It is follows of known ancient texts concerning creation and essence of our world (the Bible, Vedic and Dao). This condition is described as containing All and Nothing simultaneously. Ancient texts force us to disconnect thinking logic and to trust in supersensual perception. But a problem, we have no supersensual perception. So we shall try to create model of development of a matter with help of empirical data, existing theories and logic, but we shall take position of ancient doctrines as entry condition: "All in Nothing, Nothing in All". Is lawful to conclude on it basis that explosion reason was occurrence of Unity (point). Occurrence of Unity created occurrence of Variety potential (infinity). Unity and Variety as total difference has made explosion. The aspiration from Unity to Variety has automatically given birth to opposite aspiration from Variety to Unity. These two aspirations have created a matter, space-time, all processes and phenomena around of us and inside us. Difference of Unity and Variety, a point and infinity has given birth to space-time. Internal aspiration of superelementary particles to Unity and an external pulse to Variety have forced its to space overcoming and to participating in irreversible processes of uniting and disconnecting , that has given birth to time-line (an one-orientation from past to future) and a matter. After era of Great explosion which last very short time interval was finished an era of Great association was begun with duration no more than t=10 in degree -35s. During this period there was a first phase transition of a matter (phase transition is a change of a condition of a matter, for example, transformation of water into steam). Superelementary particles and superelementary antiparticles have appeared in this era. Here there was a global copying of Unity and Variety on internal elements of system as difference between of superelementary particles and superelementary antiparticles and occurrence of gravitation. There were first interactions and first particles focused on interactions (gluons). The following period is marked by next phase transition of matter. It is period of androns formation (protons, neutrons, electrons, etc.). Nuclear forces are basic interaction at this stage which were allocated from gravitation and have found a duality, ability to draw or push away. There were first microsystems where interactions between a few quarks form large variety of elementary particles. It is a first level of complexity known to a science. The aspiration to association at bottom level is appeared in variety at top level. All evolution of a matter proceeded by this principle.