Energy and resource analysis

Plastics are based on the common elements carbon, hydrogen, nitrogen and oxygen, and smaller amounts of chlorine and sulphur. These are among the most common elements on the surface of the earth and will never be depleted. Their cost will vary more or less, depending on the energy required to convert them into chemical intermediates. 

Strategies for resource allocation can best be evaluated on an energy cost basis, since calories (or joules) do not change over time, unlike the value of the currencies used to acquire them. A preliminary attempt to establish a basis for such analyses was given by the author in an article entitled Plastics, Energy and Ecology published in 1974 [1]. 

It is commonly believed that the natural resources of the earth are being used up, and that our fate as a species on this planet depends in a critical way on the 

Theologians have stepped in where economists fear to tread and a common view was expressed in a recent encyclical. It is stated that the advanced countries have used up so much of the world s resources that there is not enough left to bring the underdeveloped countries up to the economic levels of the developed countries. At the Environment Summit in Rio de Janeiro in 1993, it was proposed that a supemational body would be set up to ration the resource expenditures of the developed countries, particularly hydrocarbons used for fuel and energy. 

In order to consider resources in scientific terms it is necessary to make concise definitions of certain well-known phrases or terms. What, for example, is meant by growth This cannot easily be expressed in currencies, because their value changes with time. Even adjustments to constant dollars to account for inflation or deflation is not enough since many of the most important characteristics of society cannot be given a monetary value and are seldom included in common economic terms such as gross national product (GNP). Most environmentalists equate growth with consumption of resources. How then are resources consumed  

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Shenoy, U. V. (1995). Heat Exchange Network Synthesis Process Optimization by Energy and Resource Analysis. Gulf Phb. Co., Houston, TX. 

Multiobjective Analysis for Energy and Resource Conservation in an Evaporation System... 

Efficient use of both energy and resource in an evaporation system was studied based on multi-objective analysis. The exergy consumption and the total investment cost were used to measure energy and resource conservation, respectively. The trade-off curve between the two objectives shows the change in the optimal solution as the unit cost of exergy is changed. 

Nishitani, H. and Kunugita, E., "Multiobjective Analysis of Energy and Resource Conservation in an Evaporator System,"... 

Compared with conventional diesel refining process, GTL diesel offers significant environmental advantages such as less carbon emissions and improvement of air quality with the total absence of sulfur in the fuel. However, the GTL technology often requires intensive energy and resources input. This paper applies Life cycle assessment (LCA) method to quantify the environmental impacts of gas-to-liquid fuel processes. LCA is a tool for the analysis of environmental impacts of a product or a system, taking into... 

A life cycle assessment (LCA), also known as life cycle analysis, of a product or process begins with an inventory of the energy and environmental flows associated with a product from "cradle to grave" and provides information on the raw materials used from the environment, energy resources consumed, and air, water, and solid waste emissions generated. GHGs and other wastes, sinks, and emissions may then be assessed (Sheehan et ah, 1998). The net GHG emissions calculated from an LCA are usually reported per imit of product or as the carbon footprint. 

Uncertainties with the availability and suitability of biomass resources for energy production are primarily due to their varying moisture content, and to a lesser degree to their chemical composition and heating value. As the moisture content of biomass increases, the efficiency of thermal conversion process decreases. At some point more energy may have to be expended to dry the biomass than it contains. Uncertainties can be reduced by conducting a detailed chemical and physical analysis of the biomass sources. 

Classical characterization methods (gas sorption, TEM, SEM, FTIR, XPS and elemental analysis) were used to describe the resulting porous carbon structures. Temperature-dependent experiments have shown that all the various materials kept the nitrogen content almost unchanged up to 950 °C, while the thermal and oxidation stability was found to be significantly increased with N-doping as compared to all pure carbons. Last but not least, it should be emphasized that the whole material synthesis occurs in a remarkably energy and atom-efficient fashion from cheap and sustainable resources. 

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