PART V: ENERGY AND ENVIRONMENT



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Poland's Transition to a Market Economy: Prospects for Energy Efficiency and Conservation: Proceedings of the Joint Workshop of the U.S. National Academy of Sciences and the Polish Academy of Sciences on Strategies for Industrial Energy Efficiency and Conservation During the Transition to a Market Economy PART V: ENERGY AND ENVIRONMENT

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Poland's Transition to a Market Economy: Prospects for Energy Efficiency and Conservation: Proceedings of the Joint Workshop of the U.S. National Academy of Sciences and the Polish Academy of Sciences on Strategies for Industrial Energy Efficiency and Conservation During the Transition to a Market Economy This page in the original is blank.

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Poland's Transition to a Market Economy: Prospects for Energy Efficiency and Conservation: Proceedings of the Joint Workshop of the U.S. National Academy of Sciences and the Polish Academy of Sciences on Strategies for Industrial Energy Efficiency and Conservation During the Transition to a Market Economy ANTICIPATED TRENDS IN RATIONALIZATION OF ENERGY CONSUMPTION IN POLAND AND THEIR IMPACT ON AIR POLLUTION Jan Kapala and Piotr A. Kaleta Polish Academy of Sciences Institute of Environmental Engineering, Zabrze, Poland ABSTRACT Atmospheric pollution research in Poland indicates excess concentrations of sulfur dioxide, nitric oxides and suspended dust, and air quality standards for these pollutants are violated over 2.7%, 3.6%, and 5% of the nation's area, respectively. This condition results from high levels of pollutant emission from electric generation and district heating power plants contributing 88 % of total SO2 emissions and 50% of total NO2 emissions. Poland does not have domestically produced SO2 and NO2 removal technology, so we are interested in finding ways to solve air pollution problems partially by rationalization (conservation) of energy consumption. Many options for energy savings are available including: (1) increasing cogeneration of electricity and heat energy, (2) utilization of waste heat from industrial processes, particularly in the metallurgical industry, in heat distribution networks, (3) utilization of geothermal water for heating purposes, (4) elimination of irregularities in the operation of heating systems, (5) automation of the control of district heating systems, and (6) replacement of hard coal in house heating by natural gas or electricity. 1. AIR POLLUTION PROBLEMS IN POLAND Current annual primary energy consumption in Poland is about 4.95 × 1015 Btu. Per capita consumption of primary energy in Poland is lower, but not much lower, than that of highly developed countries. However, per capita consumption of electric energy in kWh per habitant per year is far lower than that of comparable countries and is lower than most countries in Europe. Comparing electric energy consumption to the primary energy consumption ratio in both Poland and Sweden, which is respectively 783 kWh/Btu and 2446 kWh/Btu we find Poland in a very disadvantageous situation [1]. Another disadvantage is the structure of energy demands in Poland, with 80% of demand being covered by hard and brown coal. To make matters worse, electric energy production is based almost 100% on coal. Consequently, power industry emissions are very hazardous for the environment. Official documents report the following pollutant emissions, in millions of tons per year: dust—2.8, sulfur dioxide —4.3, nitric oxides—1.5, and carbon monoxide—3.1. Total emissions of these pollutants are 11.7 million tons per year [4].

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Poland's Transition to a Market Economy: Prospects for Energy Efficiency and Conservation: Proceedings of the Joint Workshop of the U.S. National Academy of Sciences and the Polish Academy of Sciences on Strategies for Industrial Energy Efficiency and Conservation During the Transition to a Market Economy The main sources of nitric oxides in Poland are the electric power industry (27%), other branches of industry (27%), transportation (23%), industrial power and heat production (16%), house heating and agriculture (7%). Sulfur dioxide emissions come mainly from the electric power industry (45%), but significant amounts are also generated by house heating and agriculture (23%), industrial power and heat production (20%), other branches of industry (9.5%), and transportation (2.5%) [4]. After taking into account the sources, quantities, and emission procedures of several atmospheric pollutants, we determined the areas where permissible concentrations exceed the ambient air quality limits [Table 1]. The suspended particulate concentration exceeds the limits over 15,000 square kilometers, which amounts to 5% of the country's surface. For nitric oxides and sulfur dioxide, concentration limits are exceeded over 11,200 square kilometeres (3.6%) and 8,300 square kilometers (2.7%), respectively. The data in this table indicate the severity of the problem in Katowice province, where high concentrations of atmospheric pollutants for many years have caused the degradation of various elements of the natural environment. These data show that pollutant concentration limits are exceeded over the entire southwestern part of Poland. By means of methods of air quality determination, supported by measurements of selected pollutant parameters [2], we can establish where the limits are exceeded for other pollutants. We estimate that limits are exceeded over 4% of the country's surface for benzo(a)pyrene, 5% for lead, 3.5% for aromatic hydrocarbons, and 3.5% for carbon monoxide. Also, a significant portion of the country is contaminated by phenol, formaldehyde, and oxidants. These pollutants exceed concentration limits locally around coking plants, chemical factories, etc. All these data are confirmed by National Statistical Office. 2. GOALS FOR AIR POLLUTION CONTROL In 1988, The National Program for Environmental Improvement to the Year 2010 was established [4]. Regarding air quality protection, the following are acknowledged by this program to be principal goals: improvement of energetic fuel quality by depyrityfication of most sulfured grades of hard coal and deep desulphurization of medium-sulfured coals, providing power and thermal-electric power stations with desulfurization systems, modification of combustion processes by using fluidized bed furnaces, redesigning power boilers to provide them with low-emission burners, providing all industrial plants with dust collection plants,

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Poland's Transition to a Market Economy: Prospects for Energy Efficiency and Conservation: Proceedings of the Joint Workshop of the U.S. National Academy of Sciences and the Polish Academy of Sciences on Strategies for Industrial Energy Efficiency and Conservation During the Transition to a Market Economy providing cars with catalytic converters and introducing lead-free gasoline onto the market, and redesigning dust collection devices manufactured in Poland. As a result of these actions, pollutants emissions should be decreased to the following levels: dust: 2.1 million tons in 1995 and 2.0-2.2 million tons in 2010, sulfur dioxide: 3.5 million tons in 1995 and 2.0-2.5 million tons in 2010, nitric oxides: 1.8 million tons in 1995 and 1.0-1.2 million tons in 2010, carbon monoxide: 2.7 million tons in 1995 and 1.5-2.0 million tons in 2010. This program is ambitious but very hard to put into practice, particularly for the SO2 emissions for which removal technologies are in an initial stage [4]. 3. ENERGY CONSERVATION (RATIONALIZATION) Limitations on Poland's ability to remove pollutants make it necessary to take other actions in addition to pollution control. Improvements to heating systems in the residential and commercial sectors are very important. House heating with coal in Poland is a source of pollutants such as dust, sulfur dioxide, nitric oxides, soot, aromatic hydrocarbons, and other pollutants formed in burners working under oxygen deficiency. Pollutants emitted from such heaters are elevated only five to ten meters above the home's chimney and are not well dispersed in the air. Thus, coal-fired home heaters are noxious and make a large contribution to air pollution. Our research in the Upper Silesia Industrial Region indicates that the residential contribution to atmospheric pollutant concentration is significant: Benzo(a)pyrene—70%, tar products—50%, nitric oxides 31%, sulfur dioxide —73% and total suspended particulates— 34%. The quantities of pollutants generated by house heating are so large that pollutant concentration limits in the Katowice region would be exceeded even if industrial and other sources were eliminated. Thus, it is very important to modify the structure of energy consumption, and the most appropriate way to improve atmospheric air quality is rationalization of energy consumption. The rationalization of fuel and energy consumption depends on employing a very broad definition of an energy project to include any activity with the potential to reduce energy consumption,

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Poland's Transition to a Market Economy: Prospects for Energy Efficiency and Conservation: Proceedings of the Joint Workshop of the U.S. National Academy of Sciences and the Polish Academy of Sciences on Strategies for Industrial Energy Efficiency and Conservation During the Transition to a Market Economy developing of the technical resources required to improve the efficiency of energy use, and finding sources of funds to finance energy rationalization projects with convenient terms of credit [5]. The Polish Government has set specific goals for decreasing energy consumption in the national economy [6]: structural changes in the national economy with up to 30 million Btu savings in the year 2000 and techno-economic rationalization giving near 40 million Btu savings. However, the Polish Academy of Sciences Committee on Energetic Problems concludes that these goals are not reachable because of the deficiency of effective rationalization of energy consumption, population growth accompanying the increase of energy demands, the necessity of making up delays in power supply, and the necessity of developing modern industry. Furthermore, instead of savings, an increase in solid fuel consumption is predicted until the year 2000. This will cause increases in sulfur dioxide and nitric oxides emissions. This pessimistic assumption predicts the rise of SO2 emissions in the year 2000 by about 25% compared to 1985 emissions and an even larger increase in emissions of NOx[5]. The Polish Academy of Sciences Committee on Energetic Problems suggests the following ways to save energy in the electric power industry [7]: increasing the amount of cogeneration (combined electricity and heat production), utilizating waste heat, particularly in the metallurgical industry, utilizating low-temperature geothermal water for purposes, eliminating irregularities in the operation of district heating systems, complex automation of heating systems, replacing hard coal in residential heating by enriched energy carriers. Also, increased amounts of active power can be obtained from existing power plants by reactive power management provided with electronically controlled capacitor banks into the national power network [3].

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Poland's Transition to a Market Economy: Prospects for Energy Efficiency and Conservation: Proceedings of the Joint Workshop of the U.S. National Academy of Sciences and the Polish Academy of Sciences on Strategies for Industrial Energy Efficiency and Conservation During the Transition to a Market Economy Undertaking programs for rationalizating energy utilization simultaneously in industry, electric power production, agriculture, and residential areas can meet the energy demands without new power stations or central district heating plants until the year 2000. Consequently, further deterioration of air quality in comparison with the data in Table 1 need not occur. Moreover, modifying residential and commercial heating systems by replacing hard coal with natural and/or coke-oven gas can significantly reduce the number of areas where atmospheric pollutant concentrations exceed limits. Thus, we can expect that energy and fuel rationalization programs will have an impact on the realization of pollutant emission limitation programs, particularly in the case of oxide emissions, and consequently, on air quality improvements in many areas of Poland. REFERENCES 1. Juda, Report for Polish Academy of Sciences Committee on Energetic Problems , Warsaw 1990. 2. Kapaga, Ochrona Powietrza, 3, 1986, pp. 57-63. 3. Mantorski, personal communication, Gliwice 1990. 4. “The National Program for Environmental Improvement to the Year 2010, ” published by MOSZNiL, Warsaw 1988. 5. Filipowicz, Archiwum Energetyki 2 1988, pp. 119-160. 6. Polish Government report nr 34/84, Warsaw 1984. 7. Polish Academy of Sciences Committee on Energetic Problems Report , Warsaw 1986.

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Poland's Transition to a Market Economy: Prospects for Energy Efficiency and Conservation: Proceedings of the Joint Workshop of the U.S. National Academy of Sciences and the Polish Academy of Sciences on Strategies for Industrial Energy Efficiency and Conservation During the Transition to a Market Economy Table 1. No Province Area of exceedings in sq.km         TSP SO2 NOx 1 Katowickie KA 6650 6050 6650 2 Krakowskie KR 1210 505 630 3 Bielskie BB 1010 50 130 4 Opolskie OP 965 205 298 5 Wagbrzyskie WB 710 50 130 6 Jeleniogórskie JG 690 275 370 7 Wrocgawskie WR 605 160 245 8 Czestochowskie CZ 375 15 90 9 Kieleckie KI 360 10 45 10 Koninskie KN 275 115 195 11 Poznanskie PO 260 45 120 12 Gorzowskie GO 245 10 65 13 Bydgoskie BY 230 8 55 14 Chegmskie CH 220 0 0 15 Sieradzkie SI 200 8 35 16 Ostrogeckie OS 175 30 110 17 Tarnonobrzeskie TG 160 100 105 18 Zielonogórskie ZG 145 15 90 19 Warszawskie WA 130 12 85 20 Lubelskie LU 115 20 95 21 Radomskie RA 90 60 140 22 Lódzkie LD 75 15 90 23 Krosnienskie KS 75 10 65 24 Skierniewickie SK 75 10 90

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Poland's Transition to a Market Economy: Prospects for Energy Efficiency and Conservation: Proceedings of the Joint Workshop of the U.S. National Academy of Sciences and the Polish Academy of Sciences on Strategies for Industrial Energy Efficiency and Conservation During the Transition to a Market Economy 25 Torunskie TO 75 35 115 26 Suwalskie SU 75 10 70 27 Tarnowskie TA 65 5 20 28 Koszalinskie KO 60 5 25 29 Wgocgawskie WL 55 30 110 30 Biagostockie BK 50 10 35 31 Gdanskie GD 45 12 70 32 Zamojskie ZA 45 15 75 33 Legnickie LG 20 90 170 34 Sgupskie SL 15 0 15 35 Olsztynskie OL 12 0 0 36 Lomzynskie LO 12 10 65 37 Rzeszowskie RZ 10 8 55 38 Bialskopodlaskie BP 10 0 0 39 Nowosadeckie NS 10 0 10 40 Pilskie PI 10 0 0 41 Elblaskie EL 9 8 0 42 Szczecinskie SZ 9 5 80 43 Kaliskie KL 9 0 20 44 Przemyskie PR 6 0 10 45 Pgockie PL 6 275 380 46 Leszczynskie LE 0 0 0 47 Piotrkowskie PT 0 0 0 48 Ciechanowskie CI 0 0 0 49 Siedleckie SE 0 0 0 Total   15,653 8,298 11,253

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Poland's Transition to a Market Economy: Prospects for Energy Efficiency and Conservation: Proceedings of the Joint Workshop of the U.S. National Academy of Sciences and the Polish Academy of Sciences on Strategies for Industrial Energy Efficiency and Conservation During the Transition to a Market Economy This page in the original is blank.

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Poland's Transition to a Market Economy: Prospects for Energy Efficiency and Conservation: Proceedings of the Joint Workshop of the U.S. National Academy of Sciences and the Polish Academy of Sciences on Strategies for Industrial Energy Efficiency and Conservation During the Transition to a Market Economy CLEAN COAL TECHNOLOGY UNDER POLISH CONDITIONS Antoni Goszcz and Marian Chaber Central Mining Institute Katowice, Poland ABSTRACT The main source of energy in Poland is hard coal. However, the natural conditions in Polish coal deposits are very complicated, and exploitation of those deposits is causing serious ecological problems. The most important of these problems are disposal and utilization of mining wastes, treatment and disposal of saline water from deep mines, and coal desulfurization. Each of these problems requires special technical solutions that involve the technologies of clean coal utilization. These problems are discussed in this paper. Some projects which have been undertaken for the solution of these problems are also described. 1. INTRODUCTION The exploitation of useful minerals always interferes with the natural environment, causing changes that are mostly irreversible. Mining of coal causes some of the most severe environmental problems, considering problems directly and indirectly connected with it. Polish coal deposits have complicated tectonics. Some coal seams have a lot of ash and sulfur, and the underground waters which must be removed during mining have a high degree of mineralization. Development of clean coal technology in Poland requires the solution of problems in three areas, namely: reduction of mining wastes, the limitation of discharges of saline waters into surface waters, and desulfurization of coal. 2. THE PROBLEM OF COAL MINING WASTES The main problem in abating the environmental problems caused by coal mining is the reduction of mining wastes. Polish coal deposits have a very complicated geological structure,

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Poland's Transition to a Market Economy: Prospects for Energy Efficiency and Conservation: Proceedings of the Joint Workshop of the U.S. National Academy of Sciences and the Polish Academy of Sciences on Strategies for Industrial Energy Efficiency and Conservation During the Transition to a Market Economy Figure 1

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Poland's Transition to a Market Economy: Prospects for Energy Efficiency and Conservation: Proceedings of the Joint Workshop of the U.S. National Academy of Sciences and the Polish Academy of Sciences on Strategies for Industrial Energy Efficiency and Conservation During the Transition to a Market Economy Figure 2

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Poland's Transition to a Market Economy: Prospects for Energy Efficiency and Conservation: Proceedings of the Joint Workshop of the U.S. National Academy of Sciences and the Polish Academy of Sciences on Strategies for Industrial Energy Efficiency and Conservation During the Transition to a Market Economy Figure 3

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Poland's Transition to a Market Economy: Prospects for Energy Efficiency and Conservation: Proceedings of the Joint Workshop of the U.S. National Academy of Sciences and the Polish Academy of Sciences on Strategies for Industrial Energy Efficiency and Conservation During the Transition to a Market Economy Figure 4

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Poland's Transition to a Market Economy: Prospects for Energy Efficiency and Conservation: Proceedings of the Joint Workshop of the U.S. National Academy of Sciences and the Polish Academy of Sciences on Strategies for Industrial Energy Efficiency and Conservation During the Transition to a Market Economy Figure 5

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Poland's Transition to a Market Economy: Prospects for Energy Efficiency and Conservation: Proceedings of the Joint Workshop of the U.S. National Academy of Sciences and the Polish Academy of Sciences on Strategies for Industrial Energy Efficiency and Conservation During the Transition to a Market Economy Figure 6

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Poland's Transition to a Market Economy: Prospects for Energy Efficiency and Conservation: Proceedings of the Joint Workshop of the U.S. National Academy of Sciences and the Polish Academy of Sciences on Strategies for Industrial Energy Efficiency and Conservation During the Transition to a Market Economy This page in the original is blank.

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Poland's Transition to a Market Economy: Prospects for Energy Efficiency and Conservation: Proceedings of the Joint Workshop of the U.S. National Academy of Sciences and the Polish Academy of Sciences on Strategies for Industrial Energy Efficiency and Conservation During the Transition to a Market Economy RENEWABLE ENERGY TECHNOLOGIES IN POLAND Roman Ney Polish Academy of Sciences Minerals and Energy Economy Research Center Krakow, Poland 1. INTRODUCTION During the 1970s, after the world crude oil crisis, more rational use of fossil energy resources was observed, and there was more interest in finding new technologies of energy generation from renewables. In the 1980s, growth of ecological consciousness occurred, mainly in the highly-developed countries, caused by the recognition that some areas were showing signs of ecological disaster. In Europe there is such a zone located in the northern part of the Czech Republic, southeastern Germany, and in the Polish regions of Upper Silesia and Krakow and around the Karkonosze Mountains. region. Degradation of the natural environment has been caused by air, soil, and water pollution mainly due to energy production and conversion utilizing high sulfur coal and lignite and also due to iron and nonferrous metal industries. Environmental problems have created growing interest in renewable energy. Energy obtained from renewable sources is usually ecologically pure and only affects the environment to some limited degree, but always on a local scale. Some technologies of energy production from renewables, such as biogas production, make use of communal, agricultural, and animal waste which otherwise would cause contamination of the environment. This type of technology then plays a double role: production of energy and elimination of waste. The majority of technologies used for the use of the renewables such as water power, solar energy, wind power, geothermal energy, and biomass have been known for a long time. Some of these are characterized by rather low efficiency of conversion. Except for electric energy generation at hydropower plants and from high-temperature geothermal sources, the majority of known renewable sources of energy technologies can be used only locally. Another reason for the relatively limited use of renewables is high cost. Of considerable importance is the relatively low price of crude oil, which to a high degree dictates the prices of other conventional energy carriers. Presently, hydropower in rivers and small streams is economical, especially in the mountainous regions. Other forms of renewables compete successfully only on a small scale in remote locations far from the industrial electric energy network, gas network, and other energy carriers. The high costs of energy transport from remote energy resources to individual users such as farms or rural and urban settlements can make some renewable energy installations non-competitive. Moreover, in cold climates some forms of renewable energy can not meet the entire energy demand. However, the necessity of environmental protection makes economically justified to use renewable energy in

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Poland's Transition to a Market Economy: Prospects for Energy Efficiency and Conservation: Proceedings of the Joint Workshop of the U.S. National Academy of Sciences and the Polish Academy of Sciences on Strategies for Industrial Energy Efficiency and Conservation During the Transition to a Market Economy combination with traditional energy. Examples include thermal solar collectors combined with electric energy use and geothermal energy in district heating combined with natural gas or oil. In Poland, renewable energy use is very low. In the structure of primary energy use, it amounts only to 0.5% and combined with waste energy, the total is 1.9%. Except for the countries that utilize hydroelectricity on a large scale, such as Sweden, Canada, Japan, Austria, the U.S., and the former Soviet Union, the contribution of renewables in the structure of the primary energy balance amounts barely to 3-6%, but it is increasing. In the first half of the 21st century, participation of renewable energy in the total world use of energy could amount to 15%. It will be totally environmentally benign energy, and therefore new technologies connected with its utilization should get special preferences. 2. HYDROELECTRIC POWER Poland has limited hydroelectric energy resources. Presently, seventeen hydropower stations with a total capacity of 1860.8 MW are in operation contributing 8.25% of the total electric power system of the country. Also, during the last few years, about 350 small individual power plants with a capacity of several kW have been established by individual users. Some 18% of Poland's hydropower resource is presently in use. Utilization of water energy resources has limited environmental impact that occurs only on a local scale and only in case of large water reservoirs. Water reservoirs affect local climate, especially when they are situated in lowlands. Arable land for cultivation and forests are lost in connection with their construction. During construction of reservoirs, significant devastation of landscape occurs that often eliminates many settlements. About ten to fifteen years after construction of a water reservoir, a new ecological balance is attained. In mountainous areas, the combination of morphological conditions with unfavorable geological structure can lead to dam failure causing a catastrophe in the river basin and sudden flooding of the neighboring areas with water and rock waste. Some examples of such catastrophes have already been observed in our century. At the same time, it should be stressed that properly used energy reservoirs play an important role in flood control and can be used as a source of water supply for urban and industrial complexes and also for agriculture. 3. WIND POWER Technologies for energy production from wind power plants are on the whole environmentally friendly, although in larger installations of 30-60 kW, electric power should be placed at a distance of 200-300 meters from residences because they produce harmful noise levels. Climate conditions in Poland are not favorable for constructing wind power plants except for the Baltic seaside and some regions of central Poland. Only one third of Poland's area fulfills conditions for wind power plants with turbines up to 40 kW.

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Poland's Transition to a Market Economy: Prospects for Energy Efficiency and Conservation: Proceedings of the Joint Workshop of the U.S. National Academy of Sciences and the Polish Academy of Sciences on Strategies for Industrial Energy Efficiency and Conservation During the Transition to a Market Economy 4. DIRECT SOLAR ENERGY Thermal solar collectors, which are usually installed on the roofs of buildings, can receive in our climate on sunny days energy at the rate of 0.9 to 1.3 MJ/day/m2. The energy obtained in this way can be utilized for hot water production in single family houses. Presently, some experiments are being conducted on utilizing solar collectors for space heating in single-family homes and greenhouse heating. If thermal solar collectors are installed on the roofs of houses, they must be situated properly in relation to the sun. Generating heat power in solar collectors is ecologically pure, because the heating medium, i.e. water or some other liquid, circulates in a closed system. Thermal solar installations can be used for hot water production during the winter in combination with electric power. In this way, in the Polish climate, about 40% of traditional energy in one-family houses and in greenhouses can be supplied by solar collectors. Another form of utilizing solar energy involves photovoltaic cells, where electromotive power is generated as a result of irradiation of a semiconductor. It is achieved in photovoltaic cell assemblies in series connection in order to provide an adequate voltage and in parallel connection to provide an adequate power. In Poland research in this field is being conducted which has resulted in small installations that feed 12 V batteries. The energy they produce may be utilized at camping sites, for lighting summer cottages, and in agriculture. Photovoltaic cells may make use of scattered radiation, i.e. they can generate electric energy also on cloudy days. The efficiency of the photovoltaic cells constructed of silicon plates amounts to 11%. If doped quartz grown in a form of band crystal is used to construct the photovoltaic cells, then this efficiency can be raised to 16%. Recently, a new cell has been made in the United States which consists of three layers of gallium arsenide of various thickness. Those cells can reach 20% efficiency. This efficiency can still be raised to 25% when in those cells strong optical concentration with simultaneous cooling of the cell is applied. At present in the newest cells with plates made of alluminogallium arsenide or arsenogallium phosphide, the efficiency of energy conversion into electricity amounts to 30%. In order to increase energetic systems' efficiency and improve the economy of their exploitation, the photovoltaic cells are combined with heat collectors. In this case photovoltaic cells become the surface layer of a heat collector. Such systems permit the use of 60% of the solar radiation. The greatest number of photovoltaic power plants are in the United States, and their total power in the world amounts to 65 MW. It should be expected that on introduction of further efficiency improvements, the use of solar energy will be much wider. It is obvious that to a high degree the insolation conditions will play the decisive role. The technologies of generating energy from solar radiation are ecologically pure, and for this reason they should be developed. However, during construction of the solar power plants of several tens kW efficiency, or still larger based upon photovoltaic technology, the local natural landscape can be disrupted.

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Poland's Transition to a Market Economy: Prospects for Energy Efficiency and Conservation: Proceedings of the Joint Workshop of the U.S. National Academy of Sciences and the Polish Academy of Sciences on Strategies for Industrial Energy Efficiency and Conservation During the Transition to a Market Economy 5. BIOMASS ENERGY An important technology of energy generation is fermentation of biomass to produce biogas. One of the advantages of this technologies is utilization of the municipal and agricultural waste that provides valuable fertilizer with simultaneous production of biogas with a net caloric value from 21 to 23 MJ/m3. Analyses in Poland indicate that after the introduction of world prices for natural gas, the production of biogas will be fully profitable. Biogas production potential in Poland is estimated at 5-6 billion m3/year. 6. GEOTHERMAL ENERGY During recent years, a rather rapid development of installations utilizing geothermal energy for generating electric energy and heat energy in particular has occurred. The thermal energy of geothermal waters and also that of dry rocks originates from the energy of the heat stream of the earth, which constitutes the heat coming from the depth of the earth and the heat that is generated in the lithosphere. The earth is also heated by solar radiation. For geothermal purposes the zones of the earth with anomalously high temperatures are used. Traditionally, they are volcanic zones with superheated steam or with very hot water, which are used for electric energy generation. However, recently lower temperature sources in the range of 50-100 C have been developed for heating purposes in Italy, France, Hungary, the former Soviet Union, Japan, the U.S., the Philippines, New Zealand, and China. As the geothermal waters are usually mineralized, the modern technologies of their use require forcing the cooled waters back into the rock mass after the heat has been extracted by heat exchangers. Geothermal energy is of local character but it can cover whole regions where numerous installations can operate. It is ecologically pure energy and can be utilized in a very wide range of areas—from district heating to recreation and agriculture. Geothermal energy resources are estimated in Poland to be significant, especially in the southern part of the country. Geothermal waters with a temperature below 70 C can be utilized in winter for heating when combined with electric energy or natural gas in ways that might substantially improve the natural environment by reducing air pollution from coal burning. At present in Poland, a pilot 1.5 MW geothermal installation is being built in the sub-Carpathian region. The method of intrinsic flow to the rock mass of cooled water without the use of pumps has been worked out. The power of this installation can be raised to 11.8 MW by means of utilizing pumps and extracting heat from the water by cooling from the temperature of 86 C to 35 C. 7. CONCLUSION This paper has reviewed the potential for renewable energy development in Poland. Development and utilization of renewable energy will proceed with the improvement of technological processes in which this energy is generated and with the growth of ecological consciousness of the people.