Research on various aspects of air pollution is an integral part of Israel’s environmental policy. Such research includes epidemiological health surveys to check the impact of air pollution on the health of the population, monitoring and study of air pollutants in various sensitive areas and means of abating air pollution through improvements in the intermittent control systems operating in Haifa and Ashdod. Further details on air quality studies undertaken in Israel are included in the research chapter of this book.
Electricity Production and the Environment
The production capacity of the Israel Electric Corporation (IEC) consists of three oil-fired plants in close proximity to the coastal cities of Haifa, Ashdod and Tel Aviv, with a total capacity of 2160 MW, two coal-fired plants at Hadera and Ashkelon, with a total capacity of 2500 MW and gas turbines at various sites around the country with a total capacity of 1435 MW. IEC development plans call for an increase of about 3000 MW until the year 2000, of which 1650 MW are slated for coal-fired units and the rest for gas turbines.
Environmental supervision over the coal-fired stations in Hadera and Ashkelon is implemented within the framework of a prevention of nuisances plan, incorporated within the operational permit itself. This procedure calls for stringent regulation and control proceduresincluding the establishment of a monitoring networkto ensure that environmental quality in the region is not degraded. Environmental inspection over oil-powered stations in Haifa, Ashdod and Tel Aviv is undertaken within the framework of personal decrees published under the Abatement of Nuisances Law. These administrative orders specify the steps which must be taken by the power plants to prevent and reduce pollution.
Sulfur Dioxide Control
High levels of SO2 pollution in the metropolitan areas of Haifa and Ashdod have led to major efforts to control SO2 emissions from the power stations located in these cities. Present SO2 control for the oil-fired power plants is based on tall stacks and on the switch to low (up to 1%) and very low (up to 0.5%) sulfur fuel mandated by an intermittent control system during meteorological conditions unfavorable for the dispersion of pollutants. The use of low- sulfur fuel has increased dramatically over the years, reaching over 35% of the total oil-fired production system in 1993. Some 760,000 tons of low-sulfur fuel (compared to 465,000 in 1992) were used in the IEC’s power stations in 199340% in the Tel Aviv power station and 39% in Haifa’s power station. Very low sulfur fuel was introduced at the Haifa power plant in 1991 and at the Ashdod power station in 1993. As a result of these improvements, the ratio of SO2 emission to electricity production in 1993 decreased to less than half of its 1981 value.
To attain additional improvements in air quality in the future, the board of directors of the IEC has decided to install seawater scrubbers in its Haifa and Ashdod power stations at an investment of some $180 million. Current plans call for the first units to be equipped with scrubbers in the latter part of 1996, with additional units to be so equipped every six months thereafter. Use of scrubbers and/or the switch to low-sulfur oil or natural gas in coming years will reduce emissions to levels equivalent to 0.5% sulfur by the turn of the century.
The IEC’s coal-fired power plants do not pose significant air pollution problems due to the low-sulfur content of the coal (average of about 0.7%) and the tall stacks (250 m) at these plants. Within the framework of plans for the prevention of environmental nuisances which were established for the Hadera and Ashkelon plants, the maximum concentrations of sulfur dioxide in the vicinity of coal-fired power stations were set at half the official standard. Based on the positive experience with the existing facilities, the construction of additional coal-fired stations has been approved for the two sites. The additional power station at Ashkelon, planned for operation in 2001, will include SO2 scrubbers.
Nitrogen Oxide Control
NOx emissions are a major pollution source, but the relative contribution of the power plants to the total load of these emissions is less substantial than SO2 emissions (about 40% in contrast with 60%). Most NOx pollution is attributed to vehicular emissions.
The NOx controls planned for the new power stations are based on low NOx combustion systems in the boilers. The IEC will be using boilers which comply with the U.S. Environmental Protection Agency standard.
In recent years, many activities were undertaken to improve combustion and reduce particulate emissions in oil-fired power stations. The residual oil currently supplied in Israel contains high levels of asphaltenes which prevent complete combustion of the fuel. However as a result of improvements, including the replacement of fuel spray orifices and changes in the combustion systems of the boilers, as well as functional changes in the boilers, particulate emission rates were reduced to below the rate allowed in the personal orders (0.34 kg per million kilo-calories).
At the Haifa and Ashdod power plants, considerable reduction of particulate emissions will be attained following the installation of electrostatic precipitators with the SO2 scrubbers. Today, some improvement is being achieved as the result of increased use of low-sulfur fuel which contains about 30% less asphaltenes. An Mg- based chemical additive is used in oil-fired power stations to neutralize the acidity of the emissions and to protect the equipment from corrosion.
Israel’s coal-fired power station in Hadera was designed to attain the American emission standard in effect at that time (0.18 kg per million kilo-calories) which is equivalent to a concentration of about 135 milligram per normal cubic meter. Flue gas conditioning is carried out, when needed, to improve the function of the electrostatic precipitators. In the Ashkelon power station, as well as in new stations, the electrostatic precipitators are designed according to the new American emission standard (0.006 kg per million calories, equivalent to a concentration of 40 milligram per normal cubic meter).
Other Sources of Electricity Production
Gas turbines now form a considerable part of the installed capability of the electricity production system, but they are used sparingly due to their high operating costs. The first gas turbines to be operated in Israel (20 megawatts) were small and were based on jet engines which consume light diesel oil (0.4% sulfur). The larger new industrial gas turbines currently being built (100 and 200 megawatts) are subject to the same environmental requirements regarding the sulfur content (0.4%), as well as reduction of nitrogen oxide emissions in accordance to the USEPA standard and American stack sampling techniques.
The Ministry of Energy is currently checking the possibility of importing natural gas for the gas turbines. Natural gas is a clean, sulfur-free fuel with minimal pollutant emissions. It can be used in both the gas turbines and the fuel oil production units.
The country’s indigenous energy resources are limited: little natural gas has been found and even less oil. Thus far, oil shale is the only fossil fuel to have been discovered in Israel in substantial quantities. Oil shale for steam generation now accounts for some 3% of total energy consumption with plans underway to establish an 80 MW unit for demonstration purposes.
In Israel, the potential use of clean wind energy, as a substitute for fossil fuels, is not high (estimated at about 600 MW). The IEC has already established a wind farm in the Golan Heights with a total capacity of about 6MW.
The first wind turbine was established in the Yodfat area (the center of the Lower Galilee) in 1986 for experimentation and research, following wind measurements throughout the Galilee at 12 sites. This wind turbine supplies over 300,000 kilowatt hours per year. It is estimated that the Yodfat mountain range can contain 27 similar wind turbines, at a capacity of 300 kilowatt each, which can produce 20 million kilowatt hours per year.
The Ministry of Energy is carrying out a number of research and development projects aimed at developing renewable and/or indigenous energy sources such as solar, wind and biomass energy. The ministry’s goal is to produce 8% of Israel’s energy needs from these sources by the year 2000.
Solar Energy Research
The only energy resource Israel has in abundance is sunlight and the country is an acknowledged world leader in the development and utilization of this technology. Used mostly for domestic water heating, solar energy provides about 3.5% of the gross energy consumption.
With an average of 300 sunny days a year, Israel is an ideal laboratory for testing one of the most promising and environmentally-safe alternatives to fossil fuels: solar energy. Israel began its solar energy research soon after its establishment in 1948. Several major developments have resulted from this research: flat solar collectors for domestic use
(required in all new buildings), solar ponds and the technology of parabolic troughs developed by the now-defunct Luz corporation.
Although these efforts are already contributing hundreds of megawatts to the world’s energy budget, additional developments must be achieved: efficiency must be increased and methods to convert solar energy to storable and transportable forms must be developed. In order to develop technologies to overcome these obstacles, two major research centers are carrying out solar energy research: the Weizmann Institute of Science and the Ben-Gurion Solar Energy Research Center.
The Weizmann Institute has set up two state-of-the-art solar energy research facilities designed to test promising new technologies under realistic conditions. The Institute’s Schaefer Solar Furnace can provide 20 kilowatts of solar radiation at concentrations of more than 10,000 times the intensity of the sun. This is accomplished by means of a 100-square meter mirror that reflects the sunlight onto a seven-square-meter concentrating dish. A larger 3000-kilowatt facilitythe Canadian Institute for the Energies and Applied Researchenables technologies to be tested on an even larger scale. This facility consists of a field of 64 large computer-controlled mirrors which track the sun and concentrate its energy onto a 54-meter-high receiving tower. The energy collected by the field of mirrors is directed to several different laboratories located in a central tower. The main goals of the research performed in these laboratories are:
* Direct conversion of solar energy to electric energy using solar heated air and a modified gas turbine; * Conversion of solar energy to storable and transportable chemical energy through the splitting of water to hydrogen or other similar processes; * Conversion of solar energy to laser light to be used in the chemical industry or for remote environmental measurements from satellites.
The Ben-Gurion National Solar Energy Center at Sde Boker provides another testing ground for an array of solar-thermal facilities. All facilities at the site are monitored by a computerized system which collects and compiles performance and solar radiation data. The overall research direction at the center aims at improving the efficiency and cost-effectiveness of solar power generation on a large scale. To this end, the center uses a variety of research tools including: two grid-connected photovoltaic systems, each of several kW capacity; an oil-heating loop of linear parabolic concentrators of 960 m2 aperture and a 2,800 m2 loop of direct steam-producing parabolic troughs.
The center is active in solar radiation studies, photovoltaic research, solar-thermal research and dust research (means of suppressing the deposition of dust on the collectors of solar power stations). Moreover, it is continuing studies begun by the world’s largest manufacturer and operator of solar thermal power plants, Luz, which was forced to shut down due to financial difficulties. While demonstrating the viability of thermal oil as a heat transfer fluid in its plants, Luz was also active in the development of the Direct Steam Generation (DSG) process as a replacement to the Heat Transfer Fluid (HTF) oil circulation method. The Sde Boker facility is designed to function as a demonstration plant for the DSG technology as well as for intermediate-scale tests.
Energy conservation is probably the most effective method of reducing energy-related environmental effects. The saving potential in energy conservation is estimated as 10% of the national energy consumption. Energy conservation measures include efficient energy use by consumers, improving the efficiency of energy systems, utilizing waste energy, and switching from fossil fuels to alternative energy resources. This is achieved through technical consulting and guidance, education, initiation of legislation and regulations, and provision of incentives for energy conservation projects and surveys.
Regulations in effect since 1980 require the installation of solar water heaters in new buildings. Since 1986, new residential building must also comply with an Israeli standard which mandates thermal insulation levels that provide thermal comfort at reasonable energy consumption. Regulatory action requires large- scale industrial consumers of energy to appoint energy conservation officers, to monitor energy consumption and to undertake energy conservation surveys.
Energy conservation projects include the production and utilization of biogas, a computer program for the reduction of energy consumption in new buildings, cool storage by load shifting, and power generation from geothermal/moderate temperature heat sources.