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This paper presents an approach for solving the generation scheduling problem of a complex system consisted of conventional and renewable energy sources (RES). Wind power plants are integrated into the system in order to minimize the total thermal unit fuel costs. The gained results for wind farm power production are used as input in the system to determine the optimal amounts of generated power for the thermal generating units and hydro generating units over the study period. The optimization problem consists of minimizing the total production costs, respecting power balance equations for each time interval and all operational system constraints. The proposed approach is applied on a specific system consisted of thermal power plants (TPPs), storage hydro power plants (HPPs), pumped-storage hydro power plant (PSHPP) and wind power plant (WPP). The benefits of energy production from WPP, in terms of reducing the production costs of conventional thermal power plants are also investigated. In the proposed paper two cases are analyzed. In the two analyzed cases power unit’s generation, thermal unit’s fuel costs and stream flows of hydro units are calculated over the study period.

Во овој труд ќе биде претставена методологија на пресметка на емисијата и имисијата на гасови во атмосверата од ТЕ во Република Македонија во конкретниот случај преку модел за пресметка на концентрација на локално загадување со SO2, како и чад и пепел како составен дел на нуспродуктите од согорување на горивото при работа на термо електрaните (ТЕ). Ќе го презентираме конкретниот математичкиот модел врз основа на кој се направени програмски кодови во MATLAB и иститите искористени на конкретни примери за ТЕ во Република Македонија: ТЕ Осломеј коja работи со јаглен и ТЕ Неготино кој работи на мазут како гориво. Како влезни параметри се дадени хемискиот состав на горивото и техничките податоци за котлите и оџаците за секоја термоцентрала посебно. Како излез се добива максимална концентрација на SO2, чад и пепел и растојание од оџакот каде се појавуваат, како и распределба на истите во просторот (табеларен и графички приказ). Од анализите и конкретниот пример на термоцентралите во Република Македонија ќе се добие слика за еколошките последици врз околината како последица од експлоатација на термоенергетските постројки за производство на електрична енергија. Клучни зборови: емисија на гасови, имисија на гасови, екологија, термо електрани.

In this paper the GHG mitigation potential of a power system with prevailing use of lignite is assessed through the example of the Macedonian power system. The analysis is conducted using the WASP model in order to develop three different scenarios (business as usual – BAU and two mitigation scenarios) for the power system expansion over the period 2008–2025. In the first mitigation scenario two gas power plants with combined cycle are planned to replace some of the lignite-based capacities. The second mitigation scenario, besides the gas power plants, assumes electricity consumption reduction related to the large industrial consumers and an increased share of new renewable energy sources. Detailed calculations of the GHG emissions are made for all scenarios. The comparison of emissions in 2025 and in 2008 shows that the increase of 78% in the case of predominantly lignite BAU scenario is reduced to 41% by the first mitigation scenario, and to 14% by the second mitigation scenario. The mitigation costs appeared to be less then 10 $/t CO2-eq for the first mitigation scenario, and even negative for the second one.

The deficit of power for electricity demand reaches almost 30% for consumers in the last few years. This reflects with continually increasing the price of electricity, and today the price for small industry is almost 110Euro/MWh. The high price is additional problem for the owners in the economy crisis which is reflected with higher price of the goods. The paper gives analyses of the energy needs for real agro complex in Macedonia, private vinery with capacity of over 2 million liters in a year and with self grapes and fruits fields. The existing power supply is from grid with 10/04 kV transformer. The geographical and meteorological condition of the vinery location gives opportunity for including renewable as a power supply option for the vinery complex. After observation of the monthly energy needs for the vinery, the base scenario is the existing power supply from the distribution grid. The electricity bill in small industry has three factors: electricity in high and low tariffs in kWh and the power engaged for the technological process of production in kW. These three factors make the total electricity bill and it is over 110 Euro/MWh which is the price near competitive for renewable option. On the other side investments in renewable (especially photovoltaic (PV)) has tendency of decreasing with price of near 1,5 Euro/W. This means that renewable with PV can be real option for power supply for small industry capacities (under 500kW installed power). Therefore, the other scenarios give the option with PV and the last one includes wind option. The paper presents some scenarios for power supply of the vinery as the followings: • Base scenario of existing conventional power supply from the grid • Scenario with implementation of renewable of Photovoltaic • Scenario with implementation of renewable of Photovoltaic and Wind power The total power installed in a vinery is near 570 kW, but the maximum needs are around 250kW. At the end of the full paper some of the results from scenarios will be presented. The paper also includes the environmental impacts of the renewable scenarios, as well as financial needs for investments and revenues from renewable., {"references":["E. Holt, L. Bird: \"Emerging Markets for Renewable Energy Certificates:\nOpportunities and Challenges\". National Renewable Energy Laboratory,\nJanuary 2005.","Ruth E Weiner, Robin A. Matthews; Environmental Engineering,\nFourth Edition, Elsevier Science. Copyright 2003.","Energy Strategy in Renewable in Macedonia, MANU, Skopje 2010.","Gilbert M. Masters; Renewable and Efficient Electric Power Systems,\nJohn Wiley & Sons, Inc., publication, 2004","Bent S├©rensen ; Renewable Energy, Its physics, engineering, use,\nenvironmental impacts, economy and planning aspects, Third Edition,\nRoskilde University, 2004 by Elsevier Science.","National Energy Strategy and Strategy for Sustainable Development of\nMacedonia, Ministry of Economy."]}

Во овој текст презентирани се реланите услови Македонскиот електроенергетски систем со релано производство на електрична енергија, релана потрошувачка на електрична енергија во дадениот момент како и анализирано е влијанието на претпоставени три нови ветерни паркови. Два услови се анализирани, кога се инсталирани 25 и 50 ветерни електрани. Анализирани се напонските услови, условите во електроенергетската мрежа, трансформаторите и размената на електрична енергија со соседните електроенергетски системи.

При процесу сагоревања јаглена кои се користи као погонски медиум врши се трансформација енергије на фосилене горива од топлинске у електричне енергие при чему термоенергетскле постројке постају једне од највече загаџиваче животне средине. При процесу сагоревања јаглена као отпадне продукте – гасова појављују се: јаглероден моноксид (CO), јаглероден двооксид (CO2), азотне оксиде (NOx), сурфурни двооксид (SO2), чврсте частице (пепео и саѓе). У труду дали смо приказ емисије полутаната у воздуху од Термоелектричне централе РЕК Битола И РЕК Осломеј као највече термоенергетске централе у Републици Македоније.

The deficit of power supply in Macedonia is almost 30% or reached up to 3000 GWh in a year. The existing thermal and hydro power plants are not enough to cover the power and energy, so the import increases every year. Therefore, in order to have more domestic energy supply, the new trends in renewable and energy efficiency should be implemented in power sector. The paper gives some perspectives for development of the power system in Macedonia, taking into account the growth of electricity demand and in the same time with implementation of renewable and energy efficiency. The development of power system is made for the period up to 2030 with the period of every 5 years., {"references":["Narayan S. Rau, Walter D. Short: \"Opportunities for the Integration of\nIntermittent Renewable Resources into Networks Using Existing\nStorage\". IEEE Transactions on Energy Conversion, Vol. 11, No. 1, pp.\n181-187, March 1996.","E. Holt, L. Bird: \"Emerging Markets for Renewable Energy Certificates:\nOpportunities and Challenges\". National Renewable Energy Laboratory,\nJanuary 2005.","Donald R. Wulfinghoff; Energy Efficiency Manual,1999.","Ruth E Weiner, Robin A. Matthews; Environmental Engineering,\nFourth Edition, Elsevier Science. Copyright 2003.","National Energy Strategy in Macedonia, MANU, Skopje 2009.","Energy Strategy in Renewable in Macedonia, MANU, Skopje 2010.","A. Sørensen, L.-M. Duan, J. I. Cirac, P. Zoller, Nature 409, 63 (2000).","I. Buluta, F. Nori, Science 326, 108 (2009).","M. Riedel et al., Nature 464, 1170 (2010).\n[10] P. B¨ohi et al., Nature Phys. 5, 592 (2009).\n[11] P. Treutlein et al., Fortschr. Phys. 54, 702 (2006).\n[12] T. Hecht, Diploma Thesis, Technische Universit¨at M¨unchen Max-\nPlanck-Institut f¨ur Quantenoptik (2004).\n[13] D. Press, T. Ladd, B. Zhang, Y. Yamamoto, Nature 456, 218 (2008).\n[14] J. Berezovsky, M. H. Mikkelsen, N. G. Stoltz, L. A. Coldren, D.\nAwschalom, Science 320, 349 (2008).\n[15] D. Press et al. Nature Photonics 4, 367 (2010).\n[16] Y. Li, P. Treutlein, J. Reichel, A. Sinatra, Eur. Phys. J. B 68, 365 (2009).\n[17] E. Brion, K. Mølmer, M. Saffman, Phys. Rev. Lett. 99, 260501 (2007).\n[18] M. D. Lukin, M. Fleischhauer, R. Cote, L. M. Duan, D. Jaksch, J. I.\nCirac, P. Zoller, Phys. Rev. Lett. 87, 037901 (2001).\n[19] P. Rabl et al. Phys. Rev. Lett. 97, 033003 (2006).\n[20] M. Nielsen, I. & Chuang, Quantum computation and quantum information\n(Cambridge University Press, 2000).\n[21] S. Lloyd, Phys. Rev. Lett. 75, 346 (1995).\n[22] S. Braunstein and P. van Loock, Rev. Mod Phys. 77, 513 (2005).\n[23] J. Altepeter,D. James, P. Kwiat, Lect. Notes Phys. 649, 113 (2004).\n[24] T. Pellizzari, S. A. Gardiner, J. I. Cirac, P. Zoller, Phys. Rev. Lett. 75,\n3788 (1995).\n[25] Y. Colombe et al., Nature 450, 272 (2007).\n[26] K. Henschel, J. Majer, J. Schmiedmayer, H. Ritsch, Phys. Rev. A 82,\n033810 (2010).\n[27] T. P. Purdy, D. M. Stamper-Kurn, Appl. Phys. B 90, 401 (2008).\n[28] S. B. Zheng and G. C. Guo, Phys. Rev. Lett. 85, 2392 (2000).\n[29] T. Ladd et al., Nature 464, 45 (2010)."]}

The paper presents the impact from the new planned wind power plants on the price for the end users of electrical energy in Republic of Macedonia. In the next years, 150 MW wind power will be installed in the Macedonian electric power system. Production of electricity from wind power plants is unpredictable and of stochastic nature i.e. depends on the weather or the wind speed at the appropriate locations. Output of wind power plants is changing every minute, thus changing in the hourly level can be from 0 - 100%, even several times depending on the occurrence of winds. Changes in output of wind power plants, leads to increased demand for operational reserve in a power system. Preferential price of electrical energy from the wind power plants and increased operational reserve in the electric power system will have big impact on the final price of electrical energy in Republic of Macedonia.

Operation of coal thermal power plants (TPP) has the most destructive influence for environment mainly from GHG emission and other pollution for water and soil. Coal combustion is the process which influence with emission of carbon monoxide (CO), carbon dioxide (CO2), nitrogen oxides (NOx), sulphur dioxide (SO2), as well as PM and ash. The dominant power plant in Macedonia is lignite fired TPP Bitola with 3 units, each of 225MW installed power, or total 675 MW, and TPP Oslomej with one unit of 120 MW. The lignite consumption in Bitola is 300 t/h for one unit and 200 t/h for the unit in Oslomej. The other TPP is Negotino which is oil fired with installed power of 210 MW. Also the new gas power plants start to operate this year. The total production from thermal power units in Macedonia is near 5000 GWh in a year which covers almost 70% of the electricity demand in Macedonia. The paper presents the emission of the gases through chimney from TPPs in Macedonia mainly the concentration near the plants. The measured values will be comparing with the theoretical calculations made based on chemical content of the fuel as well based on technology for electricity production.

A rapid and profitable commercialization path for fuel cells and H2 can be executed by coordinating convergent trend in several industries. This strategy relies on existing technologies, can begin immediately, and proceeds in a logical and viable sequence. It has two preconditions: uncompromised ultra light-hybrid vehicles whose inherently high efficiency permits their full-cell stacks to rely on conveniently compact onboard thanks of compressed gaseous H2, making onboard liquid- fuel reformers unnecessary and uncompetitive; and integration of fuel-cell market development between vehicles and buildings. As a first step, fuel-cell co-or three generation could currently compete in many buildings by virtue of its thermal credit. It could yield even greater economic value wherever electric distribution grids are old or congested, or where other “distributed benefits” are important and rewarded, Its H2 could be made in the building by a mass-produced “hydrogen appliance”-either an off-peak electrolyzer or a natural-gas steam reformer. Next, the huge fuel-cell market, in buildings (which use two-thirds of all U.S. electricity), supplemented by industrial niche markets, would soon cut fuel-cell costs to levels competitive in vehicles. Low-tractive-load hyper cars could adopt fuel cells at several fold higher prices, hence several years earlier, than conventional cars. The general-vehicle market could then be opened to hydrogen by first using the spare off-peak capacity of buildings, H2 sources to serve vehicles too-particularly vehicles whose drives work or live in or near the sane buildings. Further, those vehicles daytime use as plug-in ~20+-kWe power plants could repay a significant fraction of their lease cost. This building/vehicle integration could make gaseous-H2 fueling practical without first building a new upstream bulk-supply and distribution infrastructure. It would work better and cost less than onboard liquid-hydrocarbon reforming. Ultimately it could provide more than 3 TWe of U.S. generating capacity, enough in principle to displace virtually all central thermal power stations. As both stationary and mobile applications for fuel cells built volume and cut cost for dispersed but stationary reformer and electrolyzer appliances, those H2 sources would also start to be installed freestanding outside buildings. Before, long the growing H2 market would then justify further competition from upstream bulk supply, especially from climatically benign sources. Such options include converting hydroelectric dams (or other renewables) to “ Hydro-Gen” plants that earn far higher profit by shipping each electron with a proton attached, and R.H. Wiliams,s concept of wellhead reforming of natural gas with CO2 reinjection. The latter option, s three possible profit streams-high-value hydrogen-fuel sales, enhanced hydrocarbon recovery and potential carbon-sequestration credits are already attracting large energy companies. Its ~200 year climate-safe CH4 reserves (at roughly current rates of consumption) could also provide a long bridge to a fully renewable energy system. The diverse and dynamic portfolio of hydrogen sources up and downstream; renewable and nonrenewable; based on electrolysis, reforming or other methods and with small to no net climatic effect would ensure healthy price competition and robust policy choices.