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Quiz 2;Responsible for all materials,But will emphasize topics sinceQuiz 1 and energy and costA question on Sustainable Mfgis guaranteed.

Supply chains (Steve Graves) onNov 18 may be included

How to make earrings from recycled thermoformed plastics

Ashby

Now included with process energy slides

Technology Pathways

• Electrification with renewables

• Potential use of nuclear

• Hydrogen and Carbon Capture for Heavy Industry

• Efficiency to reduce need for more land for renewables

• More efficient use of materials

• Carbon Capture

Policy and Behavior Pathways

•Consumer behavior changes

•Carbon Pricing Policy

•Stabilize deforestation

Challenges1. Energy Demand is Rising

2. Efficiency and Unexpected Results

3. Coal Remains Popular

4. Stubborn Parts – Heavy Industry, Materials, Aviation

5. Stalled Technologies – H2, biofuels, batteries

6. Long Times & Unpredictable Systems – infrastructure, politics

7. No Slippage

1. Energy Demand is Rising

Energy Consumption by Region

2. Efficiency and Unexpected Results

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13

Does Efficiency result in Conservation?

Does Efficiency result in Conservation?

Ch

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Changes in Efficiency, e, %/year

MoreUse

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𝑒Conservation

Does Efficiency result in Conservation?

Ch

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Changes in Efficiency, e, %/year

∆𝑄

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Does Efficiency result in Conservation?

Ch

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Changes in Efficiency, e, %/year

∆𝑄

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Using More

Sahni, PhD 2014

World Pig Iron

World Aluminum

World Nitrogen Fertilizer

Electricity from CoalElectricity from Oil

Electricity from Natural Gas

Freight Rail Travel

Passenger Air Travel

Motor Vehicle TravelResidential Refrigeration

Lighting UK

0

2

4

6

8

10

12

0 0.5 1 1.5 2 2.5 3 3.5 4

Ave

rage

An

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al Δ

Q/Q

(%)

Average Annual Δe/e (%)

Average annual ΔQ/Q versus average annual Δe/e

∆𝑄/𝑄>∆𝑒/𝑒

∆𝑄/𝑄<∆𝑒/𝑒

Demand

Energy Resource Efficiency

Dahmus 2014

Figure I Average annual Τ∆𝑄 𝑄 versus average annual Τ∆𝑒 𝑒 for ten activities. The time periods covered vary by activity and can be found in table I. The solids diagonal line is the line of constant resource consumption, representing the condition in which the average annual Τ∆𝑒 𝑒 is equal to the average annual Τ∆𝑄 𝑄.

Dahmus 2014

World Pig Iron

World Aluminum

World Nitrogen Fertilizer

Electricity from CoalElectricity from Oil

Electricity from Natural Gas

Freight Rail Travel

Passenger Air Travel

Motor Vehicle TravelResidential Refrigeration

Lighting UK

0

2

4

6

8

10

12

0 0.5 1 1.5 2 2.5 3 3.5 4

Ave

rage

An

nu

al Δ

Q/Q

(%)

Average Annual Δe/e (%)

Average annual ΔQ/Q versus average annual Δe/e

∆𝑄/𝑄>∆𝑒/𝑒

∆𝑄/𝑄<∆𝑒/𝑒

Demand

Energy Resource Efficiency

Dahmus 2014

Figure I Average annual Τ∆𝑄 𝑄 versus average annual Τ∆𝑒 𝑒 for ten activities. The time periods covered vary by activity and can be found in table I. The solids diagonal line is the line of constant resource consumption, representing the condition in which the average annual Τ∆𝑒 𝑒 is equal to the average annual Τ∆𝑄 𝑄.

=

𝑖=1

𝑛

22

Substitution and

New Opportunities

100m x 18m high scoreboard!

Safer parking space

Lighted softball field

What I missed… The human appetite

Examples:Recycling - plasticsMfg Process Development – 3D-PrintingRemanufacturing – powering up productsMaterials Mobilization – most elementsMIT’s pursuit of new technologies

3. Coal (fossil fuels) Remains Popular

What does the EIA say about future

energy use?

Top 10 Coal Producing Countries (2018)

Producer Amount of Coal (Gt)GDP per capita,

PPP

China 3,337.4 18, 210

India 717.1 7 ,761

Australia 409.7 51,601

Russia 338.4 27,147

United States 324.3 62,641

South Africa 258.7 13,730

Indonesia 125.9 13,056

Kazakhstan 107.3 27,830

Colombia 83.0 14,999

Poland 63.4 31,343

Rest of the World 216.6 —

World 5 981.7 —

Source: https://stats.oecd.org/BrandedView.aspx?oecd_bv_id=coal-data-en&doi=data-00465-en ; https://data.worldbank.org/indicator/NY.GDP.PCAP.PP.CD

4. Stubborn Parts: Heavy Industry & Materials, Aviation

29Gutowski, Sahni, Allwood, Ashby and Worrell, 2013

6.7MJ/kg

30(DOE)

Gutowski, Sahni, Allwood, Ashby and Worrell, 2013

8.139 kWh/kg

31

Example: Reduction of Alumina

See Appendix of Szargut for exegy values

Exergy required per mass would be 1582.4/(2X26.98) = 29.3 MJ/kg Or 29.3 (MJ/kg)/(kWh/3.6 MJ) = 8.139 kWh/kg (electricity)

32(DOE)

Gutowski, Sahni, Allwood, Ashby and Worrell, 2013

State of the Art

< 13 kWh/kg*

Worrell 2017*

𝜂 =8.139

13= 0.63

8.139 kWh/kg

Basic Reactions yield CO2

• To reduce iron ore (hemitite) use carbon (coke)

2Fe2O3 + 3C → 4Fe + 3CO2

• To make cement use limestone to make lime

CaCO3 → CaO + CO2

5. Stalled Technologies: batteries, H2, biofuels

Best Li + battery ~ 1 MJ/kg,

Tesla ~ 0.7 MJ/kg

How is Hydrogen Produced?•Steam Reforming of Methane•CH4 + 2H20 → CO2 + 4H2

•Min + CC = 17MJ/kg, NREL SMR+CC (2040) =167MJ/kg

•Electrolysis•H2O → H2 + ½ O2

•Min 118.5 MJ/kg, NREL Solid Oxide (2040) = 178MJ/kg

•Energy Intensity of H2 at STP ~ 121 MJ/kg

At STP H2 is about 0.09 g/L

38

Ref. Vaclav Smil

Building 36

MIT Campus

6. Long Times & Unpredictable Systems

Typical Life Times in the US

•Automobiles ~ 10 years

•Airplanes ~ 25 years

•Furnaces ~ 15-20 years

•Buildings ~ 30 years

• Infrastructure ~ 50 years

Lots of unattractive optionsResistance not just from vested interestsCurb our appetite – more than FreudAnd manage multiple demands – see UNSDG

17 UN Sustainable Development GoalsUN Sustainable Development Goals (SDGs)

1 poverty

2 hunger

3 health

4 education

5 gender equality

6 water and sanitation

7 energy

8 economic growth

9 industrialization and infrastructure

10 inequality

11 Cities development

12 sustainable consumption and production

13 climate change

14 oceans

15 biodiversity, forests, desertification

16 peace, justice, strong institution

17 partnerships

43

17 UN Sustainable Development GoalsUN Sustainable Development Goals (SDGs)

1 poverty

2 hunger

3 health

4 education

5 gender equality

6 water and sanitation

7 energy

8 economic growth

9 industrialization and infrastructure

10 inequality

11 cities

12 sustainable consumption and production

13 climate change

14 oceans

15 biodiversity, forests, desertification

16 peace, justice, strong institution

17 partnerships

44

There could be a silver bullet…

a functioning government

1960-1969

1970-1979

1980-1989

1990-1999

2000-2009

1960-2009

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4

5

6

7

8

-4 -3 -2 -1 0 1 2 3 4 5 6

Ave

rage

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(%)

Average Annual Δe/e (%)

U.S Residential Refrigerators and Efficiency Mandates

Decade by Decade; Trends in Demand and Efficiency

1940-1949

1950-1959

1960-19691970-1979

1980-1989

1990-1999

2000-2009

1940-2009

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Average Annual Δe/e (%)

U.S. Motor Vehicle Travel & CAFE

Figure 5 Average ΔQ/Q versus average annual Δe/e for U.S. motor vehicle travel over seven decadesFigure 6 Average ΔQ/Q versus average annual Δe/e for U.S. residential refrigeration over five decades

7. No Slippage

M.I.T. CampusSee Solving for Carbon Neutrality

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