Energy Balance

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energy balance

[′en·ər·jē ‚bal·əns]
(physics)
The arithmetic balancing of energy inputs versus outputs for an object, reactor, or other processing system; it is positive if energy is released, and negative if it is absorbed.
(physiology)
The relation of the amount of utilizable energy taken into the body to that which is employed for internal work, external work, and the growth and repair of tissues.

Energy Balance

 

in the USSR, an accounting of the extraction, processing, transporting, conversion, distribution, and consumption of energy and energy sources in the country from the point at which they are obtained to their use by the consumer.

The energy balance expresses a quantitative correspondence between the expenditure of energy and the energy made available (income of energy), including changes in the reserves of energy sources. The income side of the balance is made up of data on the extraction of energy sources; the expenditure side shows the production of the various types of energy and their distribution among consumers. Between 1940 and 1975, the extraction of energy sources in the USSR increased by a factor of 6.7, and the amount of electric energy generated increased by a factor of 21.5. In order to ensure scientific and technological progress, it is of the utmost importance that the country’s fuel and power complex be developed as efficiently, economically, and effectively as possible (see).

The principal method of analyzing the quantitative and qualitative state of the country’s energy facilities (energeticheskoe khoziaistvo) is to develop general energy balances that cover all processes from the useful consumption of all types of energy to the obtaining of the energy sources. Such balances are drawn up in choosing the optimal scheme for the energy supply of an enterprise, region, or the entire country and in determining the trends and proportions in the development of the energy facilities for the long term.

In determining economically justified proportions for the consumption of various forms of energy, special energy balances are used, such as a balance for the extraction, processing, and distribution of fuel, a balance for the consumption and production of heat, and balances for the consumption and generation of electric energy (seeFUEL BALANCE; HEAT BALANCE; and ).

Because of the fundamental importance of electric energy for the country’s economic development, the electric-energy balance is the most important part of the energy balance. Its expenditure side describes the overall demand for electric energy and the distribution of electric energy during a planning period among the various branches of the national economy; losses of electric energy during transport, distribution, and export are taken into account. The income side, which is worked out by determining the demand for electric energy, describes the structure of electric-energy production, as well as the necessary capacities of electric power plants.

The optimum energy balance is arrived at on the basis of overall economic efficiency; in other words, the optimum balance is that which entails the minimum calculated costs. Since the various forms of energy sources and energy are interchangeable, a common value for the standard, or normative, coefficient of the efficiency of capital investment is used when making calculations.

If a value of 100 percent is assigned to the potentially usable energy contained in the energy sources consumed, the energy-producing installations that run directly on fuel account for 52 percent, electric power plants for 36 percent, and boiler plants for 12 percent. Only about 40 percent of the potentially usable energy contained in the resources expended is converted into useful energy. The main losses occur in mobile energy-producing installations, in industrial furnaces, and in electric power plants. For medium- and low-temperature processes, the heat produced by electric power plants, boiler plants of various types, and individual fuel consuming installations is used. These energy-producing installations operate on coal, natural gas, and various petroleum products. For high-temperature processes the same kinds of fuel, as well as electric energy from electric power plants, are used. Stationary power plants generally use electric energy; mobile plants generally use petroleum products.

References in periodicals archive ?
Wooden building 4 levels + technical floor (attic) and reinforced concrete staircases - Foundations ballasted columns,- Certification Minergie-P-ECO and a positive energy balance,- The roof and the awning are fully covered with photovoltaic panels.
ABO's Executive Director Mary Rosenthal said algae-based fuels will be a long-term, sustainable source of fuels with significant emissions reductions, a positive energy balance, nutrient recycling and CO2 reuse.
Constant food restriction is difficult to maintain long-term and when it cannot be maintained, the result is positive energy balance (when the calories consumed are greater than the calories expended) and an increase in body mass, of which 60 percent to 80 percent is usually body fat.
Dr Jason Gill of Glasgow University explained it simply: "To put on weight you have to be in a positive energy balance - consuming more calories than you're burning.
Once conceived as a passive product of positive energy balance (stored fat), adipose tissue is actually an endocrine organ that produces peptides, steroids, and immune-function molecules to actively regulate physiology and metabolism.
The intervention group had a negative energy balance between phases (-244 kcal/day), compared with a positive energy balance for the control groups (57 kcal/day).
Historically, physiologic control mechanisms suppressed appetite and promoted physical activity, enabling most people to avoid a positive energy balance.
Results: Although there was a slight decrease in calorie intake from all treatments even during negative energy balance, the effects were more noticeable during positive energy balance.
An energy reduction strategy should be focused only on those in positive energy balance, and not on the whole population, as it will not be appropriate for all.
For optimum body shaping and weight loss, they should ensure a positive energy balance and expend more calories than they consume.
In recent years, more studies have shown a positive energy balance," says Michael Wang of Argonne (Ill.
These behaviors create periods of positive energy balance, where over time, energy intake exceeds energy expenditure, which in turn produces the gradual increases in the weight of the population that produced the obesity epidemic.

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