quiz 2; responsible for all materials, but will emphasize topics...
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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
ange
s in
dem
and
, Q,
%/y
ear
Changes in Efficiency, e, %/year
MoreUse
∆𝑄
𝑄>∆𝑒
𝑒
∆𝑄
𝑄<∆𝑒
𝑒Conservation
Does Efficiency result in Conservation?
Ch
ange
s in
dem
and
, Q,
%/y
ear
Changes in Efficiency, e, %/year
∆𝑄
𝑄>∆𝑒
𝑒
∆𝑄
𝑄<∆𝑒
𝑒Using Less
Does Efficiency result in Conservation?
Ch
ange
s in
dem
and
, Q,
%/y
ear
Changes in Efficiency, e, %/year
∆𝑄
𝑄>∆𝑒
𝑒
∆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
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.
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
0
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-4 -3 -2 -1 0 1 2 3 4 5 6
Ave
rage
An
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al Δ
Q/Q
(%)
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
0
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-1 -0.5 0 0.5 1 1.5 2 2.5
Ave
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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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