energy management: 2013/2014 primary, final & useful energies sankey diagrams class # 3 prof....

Energy Management: 2013/2014

Primary, Final & Useful EnergiesSankey Diagrams

Class # 3

Prof. Tânia [email protected]

Energy Units and Scales

• How much energy should we ingest daily?• How much energy do you spend per hour

using an electric heater?


IAASA – Global Energy Assessment 2012


Activities (kJ)



Activities (MJ-GJ or kWh=3.6MJ)



Activities (GJ-TJ or toe=41.87GJ)



Activities (GJ-TJ or toe=41.87GJ)•In early agricultural societies

– 10-20 GJ/capita/year – 2/3 for food and feed– 1/3 for cooking, heating and early industrial

activities•In UK in the mid-19th century

– 100 GJ/capita/year •In Portugal in 2010

– 108 GJ/capita/year

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 isused: 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


IAASA - Global Energy Assessment 2012

Energy Supplyenergy flows driven by resource availability and conversion technologies



The energy supply sector dealing with primary energy is referred as “upstream” activities



The energy supply sector dealing with secondary energy is referred as “downstream” activities



Energy DemandEnergy system is service driven



Quality and cost of energy services

Energetic Balance

• Where are the primary and final energies in the energetic balance?

BALANÇO ENERGÉTICOtep Total de Carvão Total de Petróleo Gás Natural

(*)

Gases o Outros

Derivados

Total de Eectricidade Calor Resíduos

IndustriaisRenováveisSem Hídrica TOTAL GERAL

2008 4 = 1 a 3 22= 15 + 21 23 30 = 24 a 29 36 = 31 a 35 37 38 46 = 39 a 45 47=4+22+23+30+36+37+38+46

IMPORTAÇÕES 1. 2 327 219 16 608 384 4 163 167 923 984 24 022 754 PRODUÇÃO DOMÉSTICA 2. 1 142 338 39 800 3 190 679 4 372 817 VARIAÇÃO DE "STOCKS" 3. - 223 603 315 673 5 960 - 837 97 193 SAÍDAS 4. 24 949 3 680 661 112 918 17 634 3 836 162

CONSUMO DE ENERGIA PRIMÁRIA 5. 2 525 873 12 612 050 4 157 207 1 953 404 39 800 3 173 882 24 462 216

PARA NOVAS FORMAS DE ENERGIA 6. 2 444 703 1 079 137 2 597 143 -2 810 996 -1 472 450 1 120 1 367 391 3 206 048

CONSUMO DO SECTOR ENERGÉTICO 7. 475 376 56 103 605 301 270 736 3 1 407 519

CONSUMO COMO MATÉRIA PRIMA 1 275 842 1 275 842

DISPONÍVEL PARA CONSUMO FINAL 8. 81 170 9 781 695 1 503 961 4 159 099 1 201 714 38 680 1 806 488 18 572 807

ACERTOS 9. 9 851 - 47 340 - 1 382 12 279 - 38 580 CONSUMO FINAL 10. 71 319 9 829 035 1 505 343 4 159 087 1 201 714 38 680 1 806 209 18 611 387 AGRICULTURA E PESCAS 10.1 358 801 3 359 87 218 2 366 21 451 765 INDÚSTRIAS EXTRACTIVAS 10.2 66 103 8 444 49 882 30 844 4 155 277

INDÚSTRIAS TRANSFORMADORAS 10.3 71 319 1 085 788 1 027 157 1 340 009 1 154 293 38 680 615 382 5 332 628

CONSTRUÇÃO E OBRAS PÚBLICAS 10.4 576 210 5 063 50 490 21 631 784

TRANSPORTES 10.5 6 680 176 6 659 46 677 3 452 6 736 964 SECTOR DOMÉSTICO 10.6 552 680 300 190 1 157 672 1 180 750 3 191 292 SERVIÇOS 10.7 509 277 154 471 1 427 139 14 211 6 579 2 111 677

Energetic Balance

• Where are the primary and final energies in the energetic balance?


(*)

Gases o Outros

Derivados



2008 4 = 1 a 3 22= 15 + 21 23 30 = 24 a 29 36 = 31 a 35 37 38 46 = 39 a 45 47=4+22+23+30+36+37+38+46

IMPORTAÇÕES 1. 2 327 219 16 608 384 4 163 167 923 984 24 022 754 PRODUÇÃO DOMÉSTICA 2. 1 142 338 39 800 3 190 679 4 372 817 VARIAÇÃO DE "STOCKS" 3. - 223 603 315 673 5 960 - 837 97 193 SAÍDAS 4. 24 949 3 680 661 112 918 17 634 3 836 162 CONSUMO DE ENERGIA PRIMÁRIA 5. 2 525 873 12 612 050 4 157 207 1 953 404 39 800 3 173 882 24 462 216



CONSUMO COMO MATÉRIA PRIMA 1 275 842 1 275 842 DISPONÍVEL PARA CONSUMO FINAL 8. 81 170 9 781 695 1 503 961 4 159 099 1 201 714 38 680 1 806 488 18 572 807

ACERTOS 9. 9 851 - 47 340 - 1 382 12 279 - 38 580 CONSUMO FINAL 10. 71 319 9 829 035 1 505 343 4 159 087 1 201 714 38 680 1 806 209 18 611 387 AGRICULTURA E PESCAS 10.1 358 801 3 359 87 218 2 366 21 451 765 INDÚSTRIAS EXTRACTIVAS 10.2 66 103 8 444 49 882 30 844 4 155 277 INDÚSTRIAS TRANSFORMADORAS 10.3 71 319 1 085 788 1 027 157 1 340 009 1 154 293 38 680 615 382 5 332 628



Energetic Balance

• Where is the useful energy in the energetic balance?


(*)

Gases o Outros

Derivados



2008 4 = 1 a 3 22= 15 + 21 23 30 = 24 a 29 36 = 31 a 35 37 38 46 = 39 a 45 47=4+22+23+30+36+37+38+46








Energetic Balance

• How do you go from final to useful energy for household electricity consumption?


(*)

Gases o Outros

Derivados



2008 4 = 1 a 3 22= 15 + 21 23 30 = 24 a 29 36 = 31 a 35 37 38 46 = 39 a 45 47=4+22+23+30+36+37+38+46








Useful Energy

• How do you go from final to useful energy for household electricity consumption?

• Electrical resistance 100%• Electrical motor

90%• Fluorescent lamp

50%• Refrigerator

200%• Heat pump 250%

,useful final i ii

E E

Sankey diagrams

• Schematic representation of the energy flow

final

primary

EE

useful

final

EE

productive

useful

EE

Miguel Águas (2009)

Sankey Diagram for Portugal for 2010

BALANÇO ENERGÉTICOtep Total de

CarvãoTotal de Petróleo Gás Natural Total de

Eletricidade

RenováveisSem

EletricidadeTOTAL GERAL

2010 4 = 1 a 3 22= 15 + 21 23 36 = 31 a 35 46 = 39 a 45 47=4+22+23+30+36+37+38+46

CONSUMO DE ENERGIA PRIMÁRIA 5. 1 656 757 11 241 129 4 506 817 2 474 507 3 168 351 23 101 751 PARA NOVAS FORMAS DE ENERGIA 6. 1 597 427 563 778 2 857 644 -2 403 968 1 819 195 2 846 994

Produtos de Petróleo 6.3 - 321 179 321 473 - 8 290 Eletricidade 6.6 1 597 427 285 397 1 740 776 -1 787 691 456 792 2 299 882 Cogeração 6.7 562 580 1 116 868 - 616 277 1 040 930 555 402

CONSUMO DO SECTOR ENERGÉTICO 7. 277 453 134 954 589 099 10 1 252 656 Consumo Próprio da Refinação 7.1 215 503 121 238 45 829 633 710 Perdas da Refinação 7.2 58 915 10 58 925 Centrais Eléctricas 7.4 3 035 128 271 131 306 Bombagem Hidroeléctrica 7.5 44 032 44 032 Perdas de Transporte e Distribuição 7.8 13 716 370 355 384 071

DISPONÍVEL PARA CONSUMO FINAL 8. 59 330 9 111 257 1 514 219 4 289 376 1 349 146 17 713 460 ACERTOS 9. 9 130 4 999 4 761 - 132 14 762 CONSUMO FINAL 10. 50 200 9 106 258 1 514 215 4 288 615 1 349 278 17 698 698 AGRICULTURA E PESCAS 10.1 360 870 3 511 88 164 65 455 009 INDÚSTRIAS EXTRATIVAS 10.2 62 582 7 951 47 271 91 151 412 INDÚSTRIAS TRANSFORMADORAS 10.3 50 200 825 308 971 726 1 331 090 590 133 5 101 671 CONSTRUÇÃO E OBRAS PÚBLICAS 10.4 493 136 9 218 52 436 554 790 TRANSPORTES 10.5 6 430 400 12 581 40 857 4 233 6 488 071 SECTOR DOMÉSTICO 10.6 679 765 300 266 1 248 873 724 980 2 953 884 SERVIÇOS 10.7 254 197 208 962 1 479 924 29 776 1 993 861

Sankey diagram for Portugal 2010

World Sankey Diagram in 2005


Regional Energy Use in 2005


• Overall 1st law efficiency in converting primary to final energy?


US – 94 EJ Portugal – 1.1 EJ

final

primary

EE

?

?useful

final

EE


• Overall 1st law efficiency in converting primary to final energy? 66%



final

primary

EE

?

?useful

final

EE


• Overall 1st law efficiency in converting primary to useful energy?



final

primary

EE

?

?useful

final

EE


• Overall 1st law efficiency in converting primary to useful energy? 34%



final

primary

EE

?

?useful

final

EE

Typical values of 1st law efficiencies

• 1st Law efficiencies from primary to final energy

• 1st Law efficiencies from final to useful energy

Sankey Diagram for an Energy Service

• Example?

Sankey Diagram for an Energy Service

• Schematic representation of the energy flow (natural gas electricity light reading)

• What is the aggregate efficiency?

productive

useful

EE

20%

50%

50%

final out

primary in

E WE Q

useful

final

EE

• What is the 1st Law efficiency in a heat pump?

Are there 1st law efficiencies > 1?

• What is the 1st Law efficiency in a heat pump?

Typical values of between 3 – 5

• What is the Sankey diagram like?

Are there 1st law efficiencies > 1?

1 11

out out

inout in

out

Q QQW Q QQ

Sankey DiagramA coal thermal power plant has an efficiency of 40%. The combustion of coal releases 7000kcal/kg. The energy consumption associated with extraction, transport and grinding represent 500 kcal/kg. 1.Draw the Sankey Diagram

A coal thermal power plant has an efficiency of 40%. The combustion of coal releases 7000kcal/kg. The energy consumption associated with extraction, transport and grinding represent 500 kcal/kg. 1.Draw the Sankey Diagram2.What is the overall efficiency?

Sankey Diagram

Coal Mine Coal at the Power Plant Electricity

40%93%

Coal at the coal mine

Coal at the Power Plant

Electricity at the Power Plant

7%

60%

1 Mcal = 4.187 MJ1 toe = 41868 MJ

A coal thermal power plant has an efficiency of 40%. The combustion of coal releases 7000kcal/kg. The energy consumption associated with extraction, transport and grinding represent 500 kcal/kg. 1.Draw the Sankey Diagram2.What is the overall efficiency?3.What is the coefficient of conversion between final and primary energy in MWhe/TOE?

Sankey Diagram


40%93%

Coal at the coal mine

Coal at the Power Plant

Electricity at the Power Plant

7%

60%

1 Mcal = 4.187 MJ1 toe = 41868 MJ

Eficiency = 2800/7500 = 37%

A coal thermal power plant has an efficiency of 40%. The combustion of coal releases 7000kcal/kg. The energy consumption associated with extraction, transport and grinding represent 500 kcal/kg. 1.Draw the Sankey Diagram2.What is the overall efficiency?3.What is the coefficient of conversion between final and primary energy in MWhe/TOE?

Sankey Diagram


40%93%

1 Mcal = 4.187 MJ1 toe = 41868 MJ

37 41868 3600MWhFinal Energy 37toe MWh4.3Primary Energy 100 toe 100 toe toe

Conversion between F.E and P.E

• Conversion coefficients are efficiencies and not direct conversions– From coal (P.E) to electricity (F.E)

– Direct conversion

• What about the conversion coefficient from natural gas to electricity?

Are first law efficiencies enough?Heating of a house can be done by one of the following methods:1.Electrical heating using the Joule effect2.Central heating 3.Heating using a heat pump

Are first law efficiencies enough?Heating of a house can be done by one of the following methods:1.Electrical heating using the Joule effect2.Central heating (burning natural gas in a furnace with a 90% efficiency)3.Heating using a heat pump (COP=3).Suppose that electricity has a production efficiency of 45% and costs 0.12 euros per kWh, natural gas is transported with a 99% efficiency, and costs 0.0708 euros per kWh.a)Compare the alternatives in terms of primary energy, final energy and cost for 1 kWh of thermal energy. Draw the Sankey Diagramsb)Discuss the investment associated with each solution.

Are first law efficiencies enough?Heating of a house can be done by one of the following methods:1.Electrical heating using the Joule effect2.Central heating (burning natural gas in a furnace with a 90% efficiency)3.Heating using a heat pump (COP=3).Suppose that electricity has a production efficiency of 45% and costs 0.12 euros per kWh, natural gas is transported with a 99% efficiency, and costs 0.0708 euros per kWh.a)Compare the alternatives in terms of primary energy, final energy and cost for 1 kWh of thermal energy. Draw the Sankey Diagramsb)Discuss the investment associated with each solution.

Electrical Resistance

Central Heating Heat Pump

Primary (kWh) 1/0.45=2.22 (1/0.90)/0.99=1.12 (1/3)/0.45=0.74

Final (kWh) 1 1/0.90=1.11 1/3=0.33

Useful (kWh) 1 1 1

Cost (euros) 1*0.12 ((1/0.9))*0.0708 1/3*0.12

Are first law efficiencies enough?

• Providing 1 kWh of heat at 30ºC to a building with an outside temperature of 4ºC

• First law efficiencies do not provide information on how much you can improve your efficiency


Central Heating

Heat Pump

Ideal Heat Pump

Final (kWh)

1 1/0.90 1/3 1/12

Useful (kWh)

1 1 1 1

First Law 100% 90% 300% 1200%

Second law efficiencies

• Ratio between 1st law real and best efficiencies • Providing 1 kWh of heat at 30ºC to a building

with an outside temperature of 4ºC

• Second law efficiencies provide information on how much you can improve your efficiency


Central Heating

Heat Pump

Ideal Heat Pump

Final (kWh) 1 1/0.90 1/3 1/12

Useful (kWh) 1 1 1 1

First Law 100% 90% 300% 1200%

Second Law 8.3% 7.5% 25% 100%

Typical values of 2nd law efficiencies

• Overall 2nd law efficiency in converting primary to final is 76% and primary to useful energy is 10%


Population (lines) Primary energy use (bars)

industrialized countries(white squares and bars) developing countries(gray triangles and bars)

Energy use data includes estimates of noncommercial energy use

Primary Energy Use 1800-2000

Grubler, A. “Energy Transitions”

Population (lines) Primary energy use (bars)

industrialized countries(white squares and bars) developing countries(gray triangles and bars)

Energy use data includes estimates of noncommercial energy use

•Primary energy use increased more than 20-fold in 200 years•Heterogeneity in per capita primary energy use:

• In industrialized countries population increased linearly while primary energy use increased exponentially until recently

• In developing countries energy use increased proportionally to population until recently

•Primary Energy Mix ?

Primary Energy Use 1800-2000



Primary Energy Mix 1850-2010




• Mostly biomass in 1850• Increasing diversification of energy vectors



• Energy Transition: The switch from an economic system dependent on one or a series of energy sources and technologies to another (Fouquet & Pearson, 2012)



Energy Transition biomass to coal



Energy Transition biomass to coal Energy Transition coal to oil



Energy Transition biomass to coal Energy Transition coal to oil

Stabilization

Energy Eras and Transitions

• Energy Transformations before industrial civilization:


• Energy Transformations before industrial civilization: – Solar radiation – food & feed, light and heat– Animate labor from humans and work animals (levers,

inclined planes, pulleys) – mechanical work & transport– Kinetic energies of water & wind – mechanical work &

transport– Biomass fuels (wood, charcoal, crop residues, dung) –

residential & industrial heat and light


• Energy Transformations before industrial civilization: – Dominant in the western world until the 2nd half of the 19th century– Dominant for most of humankind until middlle of the 20th century– Annual per capita primary energy consumption 20 GJ


• Energy Transformations that came with industrial civilization: – Fossil fuels – heat & mechanical work & transport (steam

engines, internal combustion engines and steam turbines)

Energy Transitions

• An aggregated transition to other energy source(s) includes numerous services and sectors

Energy Transitions

• The switch from an economic system dependent on one or a series of energy sources and technologies to another (Fouquet & Pearson, 2012)

16th century (tall narrow chimneys and suitable grates )17th century (coal gets even cheaper)

Energy Transitions


1709 (coke)18th century (efficiency improvments)

Energy Transitions


1804 (1st steam locomotive)

Why do energy transitions occur?

• Main Drivers/Catalyst for adoption of a new energy carrier:– Price of energy– Better/Different Service– Technological change and innovation– Efficiency improvments

Decarbonization of Energy Systems

Decreasing trend in CO2 emitted per GJ from 1850 to 2000

2010: 108 GJ/capita/year

7600 kg CO2/capita/year


Historically energy related biomass burning has not been carbon-neutral (maximum estimated value of 38%)


Why a slight increasing trend in the last 10 years?

Power generation 1990-2010

• Despite an increasing contribution across two decades, the share of non-fossil generation has failed to keep pace with the growth in generation from fossil fuels.

© OECD/IEA 2012

Ele

ctric

ity g

ener

atio

n (T

Wh)

Sha

re o

f ele

ctric

ity (%

)

Share of coal-based electricity

Share of non-fossil electricity

Nuclear

HydroNon-hydro renewables

IEA - Energy Technology Perspectives 2012

Final Energy from 1900-2000World final energy use by consumers.Solids (such as coal and biomass,brown), Liquids (such as oil, red) and fuels delivered via dedicated Grids (such as natural gas and electricity, green).



“With rising incomes, consumers pay increasing attention to convenience and cleanliness, favoring liquids and grid-delivered energy forms”



Developing countries

OECD (squares)



Heterogeneity in final energy quality


Final Energy per capita in 2010

• Heterogeneity in Final Energy Use per capita:


What is Final Energy used for?

• UK 1800-2000


What is Final Energy used for?

• Regular expansion ofenergy services in 19th

– dominated by heat and transport

• High volatility due topolitical and economic events

• Moderated growth after 1950– Decline in industrial energy services compensated by strong

growth in transport

• Saturated at a level of 6 EJ or 100 GJ/capita• What about energy services?


From Final Energy to Energy Services

• UK 1800-2000


• UK 1800-2000

• Increasing efficiencies in converting final energy to energy services– Ranges between a factor

of 5 for transportation and 600 for lighting



• UK 1800-2000• Lower prices of energy

services– Ranges between a factor

of 10 for heating and 70 for lighting



Energy Services 2005• Energy services cannot be

expressed in common units• Transport

– 13 km/day/per capita– 1 ton 20 km/day/per capita

• Industry– 9 ton/year/per capita (steel +

fertilizers + constructionmaterials + plastics …

• Buldings– Heating/cooling to 20m2/per capita

• Useful energy – minimizes distortions among

different energy service categories, as it most closely measures the actual energy service provided.

• Second law efficiencies provide information on the destruction of exergy

• What is exergy?

Power = 0 W Power = 150 kW

Δz = 0m Δz = 120m

Second law efficiencies

Energy vs. Exergy

160ºC 25ºC

Potential Work = 34 MJ Potential Work = 1.8 MJ

environment20ºC

Energy = 105 MJ Energy = 105 MJ

Exergy = 34 MJ Exergy = 1.8 MJ

energy management: 2013/2014 primary, final & useful energies sankey diagrams class # 3 prof....

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