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Text 4. Alternative Energy



Alternative energy is the use of non-conventional energy sources to generate electrical power and fuel vehicles for today’s residential, commercial, institutional and industrial energy applications. This includes emergency power systems, transportation systems, on-site electricity generation, uninterrupted power supply, combined heat and power systems, off-grid power systems and many more innovative applications.

Oil fuels the modern world. No other substance can equal the enormous impact which the use of oil has had on so many people, so rapidly, in so many ways, and in so many places around the world.

Oil in its various refined derivative forms, such as gasoline, kerosene and diesel fuel, has a unique combination of many desirable and useful characteristics. These include current availability in abundance, currently high net energy recovery, high energy density, ease of transportation and storage, relative safety, and great versatility in end use. Oil is also useful as more than an energy source. It is the basis for the manufacture of petrochemical products including plastics, medicines, paints and myriad other useful materials.

Alternative energy sources must be compared with oil in all these various attributes when their substitution for oil is considered. None appears to completely equal oil.

But oil, like other fossil fuels, is a finite resource. True, there will always be oil in the Earth, but eventually the cost to recover what remains will be beyond the value of the oil. Also, a time will be reached when the amount of energy needed to recover the oil equals or exceeds the energy in the recovered oil, at which point oil production becomes no more than a break-even, or a net energy loss situation.

Oil being the most important of our fuels today, the term ‘alternative energy’ is commonly taken to mean all other energy sources. Realizing that oil is finite in practical terms, there is increasing attention given to what alternative energy sources are available to replace oil. The imperative to develop alternative energy sources is clearly established by two simple facts.

The world now uses more than 26 billion barrels of oil a year, but new discoveries (not existing field additions) in recent years have been averaging less than seven billion barrels yearly. The peak of world oil discoveries was in the mid-1960’s. Inevitably, the time of the peak of world oil production must follow, with most current estimates ranging from the year 2003 (Campbell, 1997) to 2020 (Edwards, 1997). Significantly, all estimates of production peak dates are within the lifetimes of most people living today.

There is much casual popular thought that energy sources are easi-ly interchangeable. ‘When we run out of oil we will go to alternative fuels’. ‘We can run our cars on solar energy’. Such statements are legion. But the transition to alternative fuels will not be simple nor as convenient as is the use of oil today, and it will involve much time and financial investment. Energy carriers in terms of varied end uses and ease of handling and storage, are not easily interchangeable.

Alternative energy sources must be examined as to their advantages, limitations, and their prospects for replacing oil in the ways and great volumes in which we use oil today. Energy can be divided into renewable and nonrenewable.







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