03.08.2009

Energy quality refers to differences in the ability of a unit of energy to produce goods and services for people. The usefulness of an energy system is determined by a complex combination of physical, technical, economic, and social attributes. These include gravimetric and volumetric energy density, power density, emissions, cost and efficiency of conversion, financial risk, amenability to storage, risk to human health, and ease of transport. No single metric of an energy system captures all such attributes. It stands to reason, therefore, that a comprehensive and balanced comparison of energy technologies should employ a range of metrics, with their strengths and weaknesses duly noted. The most common way to measure energy is by heat content because all forms of energy can be completely converted to heat (Btus, joules, calories, kilowatt-hours). The aggregation of different energy types is accomplished by multiplying their mass or volume used times their heat content per unit mass or volume

Also known as the heating value. The energy content of diesel fuel is its heat of combustion; the heat released when a known quantity of fuel is burned under specific conditions. In the U.S., the heating value is usually expressed as British thermal units (Btu) per pound or per gallon at 60°F. For gross (high) heating value, the water produced by the combustion is assumed to be recondensed to a liquid. For the net (lower) heating value, the water remains as a gas. Since engines exhaust water as a gas, the net heating value is the appropriate value for comparing fuels.

The proper planning of the electricity economy has the objective to ensure the constant supply of electricity. Those responsible for the development of the electricity sector must ensure that consumption can be met especially during peak hours and it is thus incumbent to deal with two main subject matters: the supply of electricity, based inter alia on the expected installed generation capacity as well as the capacity of the transmission and distribution networks; the level of reliability of the electricity system which relies on proper maintenance and prevention of even unexpected malfunctions. The planner must also take into consideration electricity generation reserves which enable to carry out maintenance, cater for exceptional consumption demands and dealing with malfunctions. The planning of the electricity market is done based on trying to achieve financial optimization of the market place as a whole whilst understanding the cost of the non-supply of electricity. The more this non-supply costs, the higher level of reliability is required of the system and thus more electricity reserves are required.

Israel Electric Corporation (IEC) has installed a warning system to inform citizens regarding the level of reserves available. The system is based on four colors: condition green (regular electricity supply); condition yellow (consumption demand is close to available supply capacity and IEC is acting to balance the system); condition orange (consumption demand is close to the generation capacity limit and electricity blackouts are possible. IEC will update consumers so that they may act in a timely manner); condition red (consumption is higher than generation capacity and there are blackouts in certain areas. IEC is asking the cooperation of the public to re-balance the system)

Between the years 2009-2015 electricity consumption in Israel is forecasted to grow between 2%-2.5% annually, lower than the 4% annual growth previously anticipated, with demand increasing again at a higher rate after 2015 to about 3.5% annually,