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EMERGY & ENERGY SYSTEMSEMERGY & ENERGY SYSTEMS
Session 9 Short Course for ECO Interns,
EPA and Partners
Scale and Boundary DefinitionScale and Boundary Definition
• Scale and net benefits
• Timescales
Session Goals
Scale and Net BenefitsScale and Net Benefits
• Product
Scale and Net BenefitsScale and Net Benefits• Product
Data Solar EMERGYNote Description (per ha-1 yr-1) (E13 sej/yr)
Renewables1 Sun 6.35E+13 J 62 Rain 4.07E+10 J 1233 Et 6.02E+10 J 156
Non-renewables4 Net Topsoil Loss 6.33E+07 J <1
Purchased5 Fuel 7.37E+10 J 8176 Electricity 0.00E+00 J 07 Potash 1.39E+05 g K 268 Lime 3.29E+06 g 5539 Pesticides 1.59E+05 g 401
10 Phosphate 4.60E+04 g P 17011 Nitrogen 4.75E+04 g N 19212 Labor 1.20E+09 J 1613 Services 4.38E+03 $ 119914 Total EMERGY 3530
Table 1.20: Emergy Evaluation of Tomato, per ha per year
Scale and Net BenefitsScale and Net Benefits
• State/
Regional
Scale and Net BenefitsScale and Net Benefits
• Sub-process
Scale and Net BenefitsScale and Net Benefits
• Adding larger scale items into evaluation
Data Solar EMERGYNote Description (per ha-1 yr-1) (E13 sej/yr)
Renewables1 Sun 6.35E+13 J 62 Rain 4.07E+10 J 1233 Et 6.02E+10 J 156
Non-renewables4 Net Topsoil Loss 6.33E+07 J <15 Lime 3.29E+06 g 5536 Phosphate 4.60E+04 g P 1707 Gypsum treatment 2.95E+12 J 9418 H2SO4 treatment 2.51E+10 g H2O 45
Purchased9 Fuel 7.37E+10 J 81710 Electricity 0.00E+00 J 011 Potash 1.39E+05 g K 2612 Pesticides 1.59E+05 g 40113 Nitrogen 4.75E+04 g N 19214 Labor 1.20E+09 J 1615 Services 4.38E+03 $ 1199
Total EMERGY 4516
Scale and Net BenefitsScale and Net Benefits
• Net benefits– Multi-scalar
• Person• Economy• US• Planet Earth
Clinton tax credit
for high MPG cars, 1998
sej/yr
1. CO2 avoided 6.15E14
2. Gas saved3.40E15
3. $ not in circulation4.40E14
4. $ from tax credit3.60E15Benefit/Deficit
Person: 3 + 4 = 4.04E15Economy: 4 – 3 = 3.16E15
National Security: 1 + 2 – 4 = 4.10E14Global: 1 + 2 = 4.01E15
1
2
3
4No Credit
WithCredit
Scale and Net BenefitsScale and Net Benefits
• Geographic versus political– Watershed versus state or county– Environment difficult to manage from political – Data difficult to obtain for watersheds
Time ScalesTime Scales
• Short term versus long, human versus geologic– Economy evaluated annually– Renewables evaluated using long term averages– Information turnover: 2-3 months?– Cultural information: 15 – 1000 years?– Watersheds: same as dominant ecosystem?– Watersheds: same as average rain cycle?– Watersheds: same as geologic cycle?
Time ScalesTime Scales
• Cumulative versus single event– Annual flows are “snapshots”– Average flows need to encompass appropriate time period– Cumulative evaluations best used for impacts– Cumulative may be better represented by simulation