Gestão de Energia: 2016/17 Energy Analysis: Process Analysis (cont.) Primary, Final and Useful Energy Primary Energy of Primary Electricity Prof. Tânia Sousa taniasousa@tecnico.ulisboa.pt

Energy Analyis: Energy efficiency measures What is the impact of an energy efficiency measure that decreases CEA on CE12? D E C G A 11 10 9 7 5 2 F 1 4 B 3 6 12 8 EA 6

Energy Analyis: Energy & material inputs What is the meaning of E1? E1 is the total energy used to produce m1 For consistency purposes what should be the meaning of EA?

Energy Analyis: Energy & material inputs What is the meaning of E1? E1 is the total energy used to produce m1 For consistency purposes what should be the meaning of EA? EA should be the total energy used to produce that energy consumption, i.e., EA should be the primary energy associated with the final energy input How should you estimate Ea for an operation that consumes different types of energy, e.g., coal and electricity?

Energy Analyis: Energy & material inputs What is the meaning of E1? E1 is the total energy used to produce m1 For consistency purposes what should be the meaning of EA? EA should be the total energy used to produce that energy consumption, i.e., EA should be the primary energy associated with the final energy input To merge several kinds of final energy first convert each one to primary energy and then make the sum

Energy Analyis: Energy & material inputs What is the meaning of 0.215 tep/MWh for electricity?

Energy Analyis: Energy & material inputs What is the meaning of 0.215 tep/MWh for electricity? Compute the efficiency

Typical values of 1st law efficiencies 1st Law efficiencies from primary to final energy

Energy Analyis: Energy & material inputs What is the meaning of 0.215 tep/MWh for electricity? Compute the efficiency Should this factor be country-specific?

Energy Analyis: Energy & material inputs What is the meaning of 0.215 tep/MWh for electricity? Compute the efficiency Should this factor be country-specific? Does the CE of a product (same technology and the same inputs) change with the country where it is produced? Nissan Terrano (India) Renault Duster (Russia)

Forms of Energy - Primary energy

Forms of Energy - Final energy

Forms of Energy – Useful Energy

Forms of Energy Primary energy – embodied in resources as it is found in nature (coal, oil, natural gas in the ground) Final energy – sold to final consumers such as households or firms (electricity, diesel, processed natural gas) Useful energy – in the form that is used: light, heat, cooling and mechanical power (stationary or transport) Productive energy – the fraction of useful energy that we actually use

From Primary Energy to Energy Services

Primary Energy to Energy Services Energy Supply energy flows driven by resource availability and conversion technologies IAASA - Global Energy Assessment 2012

Primary Energy to Energy Services The energy supply sector dealing with primary energy is referred as “upstream” activities IAASA - Global Energy Assessment 2012

Primary Energy to Energy Services The energy supply sector dealing with secondary energy is referred as “downstream” activities IAASA - Global Energy Assessment 2012

Primary Energy to Energy Services Energy Demand Energy system is service driven IAASA - Global Energy Assessment 2012

Primary Energy to Energy Services Quality and cost of energy services IAASA - Global Energy Assessment 2012

Typical values of 1st law efficiencies 1st Law efficiencies from primary to final energy 1st Law efficiencies from final to useful energy

Primary Energy used for Electricity What is the primary energy associated with 1 kWh of (different types) of primary renewable electricity? Methods Wind Electricity Photovoltaic Hydro Electricity Geothermal Electricity “electricity produced” Electricity (1 kWh)

Primary Energy used for Electricity What is the primary energy associated with 1 kWh of (different types) of primary renewable electricity? What would be the method if we were using the concept of Primary Energy? Methods Wind Electricity Photovoltaic Hydro Electricity Geothermal Electricity “electricity produced” Electricity (1 kWh) “measure of fossil energy” 0

Primary Energy used for Electricity Resource Content Method (RCM) What is the primary energy associated with 1 kWh of (different types) of primary renewable electricity? Methods Wind Electricity Photovoltaic Hydro Electricity Geothermal Electricity “resource content method” Kinetic energy Radiation Potential Energy Heat “electricity produced” Electricity (1 kWh) “measure of fossil energy” 0

Physical Content Method (IEA) “The primary energy is the 1st energy form downstream for which multiple energy uses are pratical” Heat (nuclear, geothermal and solar thermal) Conversion from heat to electricity in geothermal is 10% and in nuclear is 30% Electricity for wind, tide/wave/ocean and solar photovoltaic (100%)

Primary Energy used for Electricity What is the primary energy associated with 1 kWh of (different types) of primary renewable electricity? Physical Content Method: primary energy is the first form of comercial energy available (IEA) Methods Wind Electricity Photovoltaic Hydro Electricity Geothermal Electricity “as it is found in nature” Kinetic energy Radiation Potential Energy Heat “electricity produced” Electricity (1 kWh) “measure of fossil energy” 0 Physical Content Method Heat (1/0.1 kWh)

Partial Substitution Method (EIA) The amount of energy that would be necessary to generate an identical amount of electricity in conventional thermal power plants Uses an average generating efficiency (40%) to convert electricity to primary energy

Primary Energy used for Electricity What is the primary energy associated with 1 kWh of (different types) of primary renewable electricity? Partial Substitution Method: primary energy is the amount of conventional energy that would have to be used (EIA) Methods Wind Electricity Photovoltaic Hydro Electricity Geothermal Electricity “as it is found in nature” Kinetic energy Radiation Potential Energy Heat “electricity produced” Electricity (1 kWh) “measure of fossil energy” 0 Physical Content Method Heat (1/0.1 kWh) Partial Substitution Method Fuel (1/0.4 kWh)

Comparison of Methods What happens to energy intensity if a country that only uses electricity (produced with coal) as final energy replaces all thermoelectric power plants with dams? With the partial substitution method? With the physical content method?

Comparison of Methods Estimate the PE with each method for a rainy and a dry year: The conversion from coal to electricity is 40%. Assume a 90% and 45% efficiencies for hydro and wind, respectively.

Comparison of Methods Estimate the PE with each method for a rainy and a dry year: The conversion from coal to electricity is 40%. Assume a 90% and 45% efficiencies for hydro and wind, respectively.

Comparison of Methods Neither the Physical Content Method nor the Partial Substitution Methods are a measure of primary fossil energy Growth of wind, hydro or solar to produce electricity leads to primary energy savings with the Physical Content Method

Exercise A factory produces 2 end products: P1 and P2. These products follow the production process shown in the diagram below, with P1 = 50000 ton/year and P2 = 30000 ton/year. The operation G treats the effluents from E and F. These two (E and F) are the only productive operations that generate waste, and SE = 1.2, SF = 1.3. In operation G, only 20% of the input effluent, exits the process as waste. The values of composition are as follows: f4 = 0.4, f6 = 0.5. The table presents the specific consumption of each operation. Consider that for electricity: 0.215 kgep/kWh and for fueloil 0.984 kgep/kg. Calculate f13 8 (produção 1)   A C D E B 2 1 F G 14 13 12 11 10 (produção 2) 3 4 5 6 7 9

Exercise 3800 8 (produção 1)   A C D E B 2 1 F G 14 13 12 11 15200 10000 30000 30000 50000 42400 27600 30000 9000 41400 30000 41400 39000

Exercise A factory produces 2 end products: P1 and P2. These products follow the production process shown in the diagram below, with P1 = 50000 ton/year and P2 = 30000 ton/year. The operation G treats the effluents from E and F. These two (E and F) are the only productive operations that generate waste, and SE = 1.2, SF = 1.3. In operation G, only 20% of the input effluent, exits the process as waste. The values of composition are as follows: f4 = 0.4, f6 = 0.5. The table presents the specific consumption of each operation. Consider that for electricity: 0.215 kgep/kWh and for fueloil 0.984 kgep/kg. What is the specific consumption of each operation?

Exercise

Exercise A factory produces 2 end products: P1 and P2. These products follow the production process shown in the diagram below, with P1 = 50000 ton/year and P2 = 30000 ton/year. The operation G treats the effluents from E and F. These two (E and F) are the only productive operations that generate waste, and SE = 1.2, SF = 1.3. In operation G, only 20% of the input effluent, exits the process as waste. The values of composition are as follows: f4 = 0.4, f6 = 0.5. The table presents the specific consumption of each operation. Consider that for electricity: 0.215 kgep/kWh and for fueloil 0.984 kgep/kg. What is the specific consumption of each product? 8 (produção 1)   A C D E B 2 1 F G 14 13 12 11 10 (produção 2) 3 4 5 6 7 9

Exercise

Exercise A factory produces 2 end products: P1 and P2. These products follow the production process shown in the diagram below, with P1 = 50000 ton/year and P2 = 30000 ton/year. The operation G treats the effluents from E and F. These two (E and F) are the only productive operations that generate waste, and SE = 1.2, SF = 1.3. In operation G, only 20% of the input effluent, exits the process as waste. The values of composition are as follows: f4 = 0.4, f6 = 0.5. The table presents the specific consumption of each operation. Consider that for electricity: 0.215 kgep/kWh and for fueloil 0.984 kgep/kg. In which product will a measure of energy savings implemented in the operation A reduce more the specific consumption? 8 (produção 1)   A C D E B 2 1 F G 14 13 12 11 10 (produção 2) 3 4 5 6 7 9

Exercise