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Gemini Center Energy and Climatization Energy and Environment (1) Professor Vojislav Novakovic, PhD Department for Energy and Process Engineering Norwegian University of Science and Technology PhD Program “Sustainable Energy and Environment in Western Balkans” Third joint seminar: Energy and Environment Faculty of Mechanical Engineering, East Sarajevo, Bosnia and Herzegovina, 21-24 May 2007
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Gemini Center Energy and Climatization Energy and Environment Outline World energy challenge Demands for energy Forms of energy Quality of energy Energy conversion Coefficients of efficiency Holistic approach to energy efficiency in buildings
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Gemini Center Energy and Climatization Challenges the World Is Facing Today To secure enough Food and Energy For rapidly increasing population Reduce the environmental impact
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Gemini Center Energy and Climatization Demand for Energy = Demand for Energy Services Energy covers our requirements Basic needs Preparation of food Heating Personal hygiene Light Work Needs of the industrial society Production Transportation Goods Commodities
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Gemini Center Energy and Climatization Losses Energy Use and Its Impact on the Environment Sources of energy Sun Water Oil Gas Coal Nuclear Bio Wind Ocean Energy services Heating Cooling Work Light Emissions of CO 2, NO x, SO 2,...
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Gemini Center Energy and Climatization
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Heat Balance for the Earth (TW) Solar irradiation is more than 10.000 times larger than the energy utilized by people on the Earth Photosynthesis utilize 10 times more energy than people on the Earth use
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Gemini Center Energy and Climatization Forms of Energy Potential Kinetic Mechanical Electric Heat Internal Chemical Nuclear Electromagnetic radiation
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Gemini Center Energy and Climatization Renewable Energy Resources Solar radiation Hydro Wind Ocean related energy Wave, tidal, thermal gradient, salinity gradient Chemical energy Crops, wood, forest residues, waste Geothermal Internal
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Gemini Center Energy and Climatization Non-Renewable Energy Resources Chemical energy Fossil fuels coal, oil, gas, peat, tarf, oil shale, marlstone, tar sand Nuclear energy Uranium
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Gemini Center Energy and Climatization Relation Resources - Reserves When resources are: Exactly proven and Exploitation is profitable Resources become reserves Reserves Proven Not discovered Profitable Not profitable Resources
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Gemini Center Energy and Climatization The Basic Laws of Thermodynamics The First Law of Thermodynamics Law of energy conservation Energy and materials are always conserved They can be neither created or destroyed Only converted from one state or form to another
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Gemini Center Energy and Climatization Conversion of Energy Heat production Solar Geothermal Combustion Electricity Heat pumps Nuclear Electricity production Solar Hydro Wind Wave Tidewater Geothermal Combustion Nuclear Fission
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Gemini Center Energy and Climatization Conversion of Energy Electricity Production Heat power plants Solar energy Photosynthesis Carbonization Combustion Heat Mechanical work Electricity Hydro power plants Solar energy Evaporation Condensation Elevation Motion Mechanical work Electricity
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Gemini Center Energy and Climatization Water Cycle in the Nature
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Gemini Center Energy and Climatization Hydro Power Station Headwater level Turbine Water tunnel Generator Tailwater level
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Gemini Center Energy and Climatization The Basic Laws of Thermodynamics The Second Law of Thermodynamics Law of energy quality Explain to which extent the conversion from one form of energy to an other is possible Quality of energy – there are three grades of energy quality Mechanical energy is the energy form with higher quality than heat energy
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Gemini Center Energy and Climatization Quality of Energy Maximum Achievable Amount of Mechanical Work EQ = ----------------------------------- Supplied Energy W max EQ = -------- Q
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Gemini Center Energy and Climatization Three Grades of Energy Energy of 1.Grade might be converted to any other form of energy without any limitations Mechanical: work, potential, kinetic, pressure Electrical: electromagnetic (sun), electrostatic Chemical: fuels Nuclear: fission, fusion Pure Exergy
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Gemini Center Energy and Climatization Three Grades of Energy Energy of 2.Grade might be converted to other forms of energy but only to a limited extent Thermal:heat Internal:temperature, state change Mixture of Exergy and Anergi
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Gemini Center Energy and Climatization Three Grades of Energy Energy of 3.Grade can not be converted to any other form of energy Internal energy in surroundings Pure Anergi
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Gemini Center Energy and Climatization The Basic Laws of Thermodynamics 1.Law Energy = Exergy + Anergi 2.Law Portions of either Exergy or Anergi might be equal to zero Exergy high quality energy which could be converted to useful work Anergi low quality energy which is not possible to convert to exergy
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Gemini Center Energy and Climatization Quality of Thermal Energy Exergy Anergi Energy Tr – The temperature at which the heat is delivered To – The temperature of the surroundings
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Gemini Center Energy and Climatization Quality of Energy for Heat Source W max T source - T surroundings EQ = ------- = ---------------- QT source Absolute temperature T [K] = t [C] + 273,16
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Gemini Center Energy and Climatization Quality of Energy for Heat Source Temperature of the heat source [C] Quality of Energy 20000,880 15000,856 10000,786 5000,646 2500,478 1000,268 500,155 200,068 00,000
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Gemini Center Energy and Climatization Example: Gas fired power plant Combustion products 1500 - 2000 C EK = 0,88 Limitation of material 1200 - 1300 C EK = 0,60 Energy loss in cooling water t = 20 C EK = 0,10
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Gemini Center Energy and Climatization Quality of Energy for Heat Supply What temperature demand do we have for the heat that is supplied T need W min T need - T surroundings EQ = ------- = --------------- QT need
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Gemini Center Energy and Climatization Quality of Energy for Heat Supply Temperature demand [C]Quality of Energy 10000,786 5000,646 2500,478 1000,268 800,227 600,180 400,128 200,068 00,000
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Gemini Center Energy and Climatization Quality of Energy for Space Heating Energy:Q = Exergy + Anergi = 100% Exergy:E = Q (T r -T o ) / T r E = 100% (295-273)/295 = 7,5% Anergi:B = Q T o / T r E = 100% 273/295 = 92,5%
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Gemini Center Energy and Climatization Utilization of Energy Efficiency of energy utilization Useful energy versus energy input Coefficient of efficiency Commercial coefficient Useful energy versus theoretically achievable Coefficient of performance Environmental coefficient
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Gemini Center Energy and Climatization Coefficient of Efficiency Useful energy Q in -Q loss = --------------- = --------- Energy inputQ in tot = a b c d ...
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Gemini Center Energy and Climatization Coefficient of Efficiency for Hydro Power Production in Norway All figures are in TWh Storage = 120 / 131 = 0,92 Production = 104 / 120 = 0,87 Distribution = 95 / 104 = 0,91 Total = 0,92 0,87 0,91= 0,72
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Gemini Center Energy and Climatization Coefficients of Efficiency for Energy Conversion Wood-burning stove75 % Kerosene stove80 % Central domestic heating80 % Thermal power plant (coal)45 % Thermal power plant (gas)52 % Hydro-electric power station87 % Electricity generator98 % Photovoltaic cell16 %
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Gemini Center Energy and Climatization Why Do We Build Buildings ? To protect our selves and our private property against: The external climate – rain, snow, wind, sun etc Disturbances from other peoples To create good and safe conditions for all our indoor activities in: Houses: Preparing food, eating, catering for personal hygiene requirements, sleeping, doing hobbies, etc Commercial, industrial or service buildings: Working, or receiving various types of services
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Gemini Center Energy and Climatization Net End Use of Energy in Onshore Norway in 2005: 225 TWh Energy sources Transportation Industry Buildings
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Gemini Center Energy and Climatization Demands That We Place on Our Buildings To provide a healthy and comfortable indoor environment To be economical regarding investments and operational expenses To be reliable and safe without negative impacts on the outdoor environment
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Gemini Center Energy and Climatization Energy Efficiency in Buildings Outdoor environment Building envelope Technical installations Building owners and users Outdoor temperature Basic design Energy supply/ transformation Behavior Habits Solar radiationThermal insulation Heating/Cooling Ventilation Activity Working hours WindAir tightness Air handling Heat recovery Sundry gains MoistureHeat capacity Lighting Automatic controls Operation Maintenance SurroundingsFenestration Dom.hot water Sanitary Management Development ENERGY CONSUMPTION - INDOOR ENVIRONMENT COSTS OF OPERATION
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Gemini Center Energy and Climatization Energy and Environment Summary World energy challenge Demands for energy Forms of energy Quality of energy Energy conversion Coefficients of efficiency Holistic approach to energy efficiency in buildings
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Gemini Center Energy and Climatization Energy and Environment * The End * Fin * Konec * Slutt * Kraj * Хвала на пажњи !
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