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Summarize the text in four paragraphs.

Energy Gap: Crisis for Humanity?

The reason for concern can b found in set of factors which r pulling in glaringly different directions:

Demand for energy, in all its forms, is rising.

Supplies of key fuels, notably oil and gas, show signs of decline.

Main-stream climate science suggests that reducing greenhouse gas emissions within two decades would b prudent thing to do.

Meanwhile the Earth's population continues to rise, with the majority of its six billion people hankering after richer lifestyle - which means greater consumption of energy.

Underlying the growing concern is the relentless pursuit of economic growth, which historically has bn tied to energy consumption as closely as horse is tethered to its cart. The immediate question is whether the crash comes soon, r whether humanity has time to plan comfortable way out. Even if it can, the planning is not necessarily going to b easy, r result in cheap solutions. Every energy source has its downside; there is n free lunch, wherever you look n the menu.

The International Energy Agency (IEA) predicts rise in global energy demand of 50-60 % b 2030. If all else remained equal, that rising demand would b accommodated principally b fossil fuels, which have generally bn the cheapest and most convenient available. But oil supplies show signs of running down; this, combined with concerns about rising demand and political instability, conspired to force prices up from $40 barrel at the beginning of 2005 to $60 at its close. The oil-producing countries and companies are prn to exaggerate the size of their stocks.

Natural gas stocks - in recent times the fuel of choice for electricity generation r also showing signs of depletion, and there is growing concern in Western capitals about the political instability associated with oil and gas supplies from the Middle East and Russia. Coal, the fuel of the industrial revolution, remains relatively abundant; but here the climate issue raises its provocative head most volubly, because of all fuels, coal produces mr greenhouse gas emissions for the energy it gives. Based partly n the predicted availability of cheap coal, the IEA forecasts 50 % rise in greenhouse gas emissions b 2030. Mainstream climate science, meanwhile, indicates that to avoid dangerous consequences of climate change, emissions should fall, not rise, b 50 %. The economic and environmental horses r clearly pulling in mutually incompatible directions.

Nuclear fission is at the head of the queue. According to the World Nuclear Association, there r now about 440 commercial reactors in the world, providing 16 % of its electricity. But concerns over waste have set other countries such as Germany n determinedly non-nuclear path. Waste apart, nuclear faces another potential obstacle; stocks of uranium r finite. Analysts differ over how soon uranium deficit might emerge; some believe that significant ramping up of nuclear capacity would exhaust economic reserves n timescale of decades. That could b extended b adopting ``fast breeder'' reactors, which create mr fissile material as they go. Too good to b true? Perhaps, because there is major downside: the creation of plutonium, with its attendant dangers of proliferation. The other nuclear technology, fusion, is full of hope but even its most ardent supporters admit it is decades away.



Most of the energy we use n Earth comes directly r indirectly from the Sun. It is the Sun which stirs winds and the great water cycle, depositing rain n highlands, grew plants which decayed to form the coal and oil that we have extracted so determinedly in our industrial age. Is it now time, then, to use its energy directly. Certainly it could b done, but at costs up to five times that of coal and gas, it is not going to b soon. Wind, wave and tidal power r all fine technologies, but their potential is limited, not least b the fact that they do not generate continuously. That could b overcome b storing energy. Hydrogen, meanwhile, is touted as the great climate-friendly hope. But hydrogen is just carrier of energy. It must b created, for example b using electricity to split water molecules, in which case replacing petrol-driven cars with hydrogen vehicles would vastly increase the global demand for electricity. No free lunch, indeed - but desperately tortuous and risk-laden menu and kitchen where political r environmental fires could flare up at n moment. ( NEWS, 14.01.06.)


Date: 2016-01-03; view: 628


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