Energy in Green Building:The Carbon Imperative and     the Ruby Slippers         Dr. Alexandra “Sascha” von MeierProfessor...
Natural carbon cycle               ≈ 50 GtC/y                                               CO2 emissions                 ...
CO2 removal fromatmosphere ≈ 3 GtC/y        CO2 emissions        ≈ 7 GtC/y
7   800          3
Burning fossil fuel means combustion of hydrocarbons: CXHY +            O2 → CO2 + H2Ohydrocarbon + oxygen → carbon dioxid...
GISS analysis of global surface temperature; 2008 point is 11-month mean.                                              Sou...
Five Stages of ReceivingCatastrophic NewsDenialAngerBargainingDepressionAcceptance
Source: Arctic Council and International Arctic Science Committee, www.acia.uaf.edu
Slide: John Holdren
Climate stabilization (at 450 ppm CO2) requires global emissions to peak by 2015and to fall to ~80% below 2000 levels by 2...
California’s Big Step Forward:                                                                           Assembly Bill 32 ...
American Heritage Dictionary, 10th ed.
Physical Meaning of Energy:Energy = the ability to do work                                                       Force    ...
Energy = the ability to do workPotential energy = mgh(mass, gravitational acceleration, height)                           ...
Examples of EnergyNatural gas in the pipeline            (chemical)Gas flame on my kitchen stove          (chemical to the...
Because a measurable quantity of energy is conservedduring any conversion of one form to another,it makes sense to give a ...
Matter and Energy Resources“High Quality” means            High quality energy:        concentrated            mechanical,...
2nd Law requires:Some of the chemical fuel energy will be degraded into heat.The amount of mechanical work or electricity ...
Basic lesson:Use energy sources matched in quality with end use needs.
Units of energy:              Units of power:calories                      calories per hourkilocaloriesjoules            ...
Electric usage    232 kWh        $0.11/kWhGas usage         52 therms      $0.71/thermConversion factors:       1 therm = ...
Electric usage        232 kWh          $0.11/kWhGas usage             52 therms        $0.71/thermConversion factors:     ...
$ 0.115 / kWhPG&E electric rates have stayed about the sameover the past five years
$ 1.04 / therm                              $ 0.92 / thermPG&E gas rates have gone up from $0.70 / therm
Electric rate       $ 0.115 / kWhGas rate            $ 0.92 – 1.04 / thermWhich is more expensive, gas or electricity?Conv...
Time for a break, maybe?
Basic Passive Solar Design Problem:Get solar heat when you want it, not when you don’t.Careful:Windows can be net gain or ...
The Environmental Technology Center at Sonoma State University
Passive Solar Design Principle #1:Think about where the sun is going to be.
from Miller, Living in the Environment
Note different scales for power radiated!
Thermal IR
Passive Solar Design Principle #2:Remember conduction, convection and radiative heat transfer.
Q = m c ∆TQ is amount of heat storedm is massc is specific heat∆T is temperature difference before/after
Outside and Inside Temperatures                     100                      90Degrees Fahrenheit                      80 ...
Passive Solar Design Principle #3:Store warmth or coolth in thermal mass.
R-value: thermal resistanceU-value: thermal conductance, R = 1/U
Heat flow example:R-20 wallU = 0.05 Btu/h-ft2-oFArea = 100 ft2∆T = 30oFWhat is the rate of heat loss?Q = U A ∆T  = (0.05 B...
Note:U-value is weighted average of framing and area between framing.Any air gap between insulation & framing ruins the in...
Ballpark value for residential building envelope:UA = 500 Btu/h-oFHow much heating energy does it take?Convenient characte...
443 Degree-Daysin San Francisco for themonth of January3001 Degree-Daysfor the whole yearFor example:300 days of ∆T = 10oF
UA = 500 Btu/h-oFHow much heating energy does it take?San Francisco heating climate: 3001 DDQ = U A ∆T-days × hours/day   ...
Passive Solar Design Principle #4:Insulate well.
SHGC: fraction of solar gain admittedthrough windowPerformance trade-off with U-valuefor solar heatingU-value: thermal con...
Passive Solar Design Principle #5:Be smart about windows.
Passive Solar Design Principle #1:Think about where the sun is going to be.#2Remember conduction, convection and radiative...
Heat loss by conduction,                                      convection and                                      infrared...
Heat gain by conduction,                  convection and                  infrared radiationHeat gain bysolar radiation
Heat loss by conduction,                         convection and                         infrared radiationHeat gain from n...
Question: Should I turn the heater off            Heat loss by conduction,while I’m gone?                                 ...
Basic principle for smart energy use in any building:Think of heat flow through the envelope.
Solar collectors for domestic hot water
Focusing with a parabolic mirror
If you use solar energy, yourchildren will be well-groomed, polite and gladlyhelp with chores.
Solar Thermal Power at Kramer Junction, CA   Photo: PG&E
Photo: Pacific Gas & Electric
Vestas 1.8 MW 260’ height, 135’ radius   www.tva.gov
Interesting constraints:Transmission infrastructureResource location, cooling waterEnergy storage capacityTemporal coordin...
Drastic reductions of carbon emissionsThree investment strategies:Energy efficiencyplus• carbon capture                   ...
Image: IPCC
South Texas Project, Photo: www.nielsen-wurster.com
CCS:     Carbon Capture and Storage or         Carbon Capture and SequestrationProblematic issues:•   sheer quantity of ca...
Nuclear energyProblematic issues:• “vulnerability to human frailty, incl. stupidity and malice”    (John Holdren)• slow, c...
Portfolio of renewable energy resourcesProblematic issues:• spatial and temporal constraints on energy availability• requi...
Pacific Gas & Electric, 1989
Exclusion zone radius 18 km, area 109 m2Incident solar radiation 1000 W/m2at conversion efficiency 0.1could generate 108 k...
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
Energy in green building and the carbon imperative
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Energy in green building and the carbon imperative

  1. 1. Energy in Green Building:The Carbon Imperative and the Ruby Slippers Dr. Alexandra “Sascha” von MeierProfessor, Dept. of Environmental Studies & Planning Sonoma State University www.sonoma.edu/ensp
  2. 2. Natural carbon cycle ≈ 50 GtC/y CO2 emissions ≈ 7 GtC/y1 GtC/y = 1 billion tons of carbon per year,which may be bound in CO2 or other compounds
  3. 3. CO2 removal fromatmosphere ≈ 3 GtC/y CO2 emissions ≈ 7 GtC/y
  4. 4. 7 800 3
  5. 5. Burning fossil fuel means combustion of hydrocarbons: CXHY + O2 → CO2 + H2Ohydrocarbon + oxygen → carbon dioxide + waterwhere the proportions of CO2 and H2O depend on X and Y
  6. 6. GISS analysis of global surface temperature; 2008 point is 11-month mean. Source: Jim Hansen, 2008
  7. 7. Five Stages of ReceivingCatastrophic NewsDenialAngerBargainingDepressionAcceptance
  8. 8. Source: Arctic Council and International Arctic Science Committee, www.acia.uaf.edu
  9. 9. Slide: John Holdren
  10. 10. Climate stabilization (at 450 ppm CO2) requires global emissions to peak by 2015and to fall to ~80% below 2000 levels by 2050 Slide: Jim Williams Source: Intergovernmental Panel on Climate Change, Climate Change 2007: Synthesis Report
  11. 11. California’s Big Step Forward: Assembly Bill 32 600 Historical Emissions Inventory 2008 Estimate 500 2020 Goal under AB32 Million metric tonnes CO2e 400 Electricity 300 Transportation 200 2050 Target (EO 03-05) 100 Industry 2050 Goal Executive orderSlide: 0 1990 1993 1996 1999 2002 2005 2008 2011 2014 2017 2020 2023 2026 2029 2032 2035 2038 2041 2044 2047 2050Snuller Price
  12. 12. American Heritage Dictionary, 10th ed.
  13. 13. Physical Meaning of Energy:Energy = the ability to do work Force distance Work = Force · distance
  14. 14. Energy = the ability to do workPotential energy = mgh(mass, gravitational acceleration, height) velocity Kinetic energy = ½ mv2 (mass, velocity)
  15. 15. Examples of EnergyNatural gas in the pipeline (chemical)Gas flame on my kitchen stove (chemical to thermal)Hot water in the kettle (thermal)Electricity in the wall outlet (electrical)Spinning blade of the coffee grinder (mechanical kinetic)Pancakes & maple syrup (chemical)Vase sitting on top shelf (mechanical potential)Vase falling down to floor (mechanical kinetic)Radioactivity (nuclear to radiant)Sunshine (radiant to thermal)Wind (mechanical kinetic)
  16. 16. Because a measurable quantity of energy is conservedduring any conversion of one form to another,it makes sense to give a single name to that quantity.
  17. 17. Matter and Energy Resources“High Quality” means High quality energy: concentrated mechanical, electrical, radiant pure easy to use in an orderly state Medium quality energy: nuclear, chemical“Low Quality” means dispersed impure more difficult to use Low quality energy: disordered thermal (heat)
  18. 18. 2nd Law requires:Some of the chemical fuel energy will be degraded into heat.The amount of mechanical work or electricity produced will be lessthan the fuel input.
  19. 19. Basic lesson:Use energy sources matched in quality with end use needs.
  20. 20. Units of energy: Units of power:calories calories per hourkilocaloriesjoules joules per second = wattskilowatt-hours (kWh) kilowatts (kW)British Thermal Units (BTU) BTU per hourtherms (105 BTU)quads (1015 BTU) Power = energy per unit time
  21. 21. Electric usage 232 kWh $0.11/kWhGas usage 52 therms $0.71/thermConversion factors: 1 therm = 100,000 Btu = 105 Btu 1 kWh = 3,413 BtuQuestions:• Which is my greater energy consumption – electricity or gas?• Which is more expensive per unit energy – electricity or gas?
  22. 22. Electric usage 232 kWh $0.11/kWhGas usage 52 therms $0.71/thermConversion factors: 1 therm = 100,000 Btu = 105 Btu 1 kWh = 3,413 BtuConvert 232 kWh into therms by multiplyingby the conversion factors (3,413 Btu / kWh) and (1 therm / 105 Btu):232 kWh x (3,413 Btu / kWh) x (1 therm / 105 Btu) = 7.9 therms → I use 7.9 therms worth of electricity
  23. 23. $ 0.115 / kWhPG&E electric rates have stayed about the sameover the past five years
  24. 24. $ 1.04 / therm $ 0.92 / thermPG&E gas rates have gone up from $0.70 / therm
  25. 25. Electric rate $ 0.115 / kWhGas rate $ 0.92 – 1.04 / thermWhich is more expensive, gas or electricity?Conversion factors: 1 therm = 100,000 Btu = 105 Btu 1 kWh = 3,412 Btu$0.115/kWh x (1 kWh/3,412 Btu) x (105 Btu/therm) = $3.37/therm→ electricity is over three times as expensive as natural gas
  26. 26. Time for a break, maybe?
  27. 27. Basic Passive Solar Design Problem:Get solar heat when you want it, not when you don’t.Careful:Windows can be net gain or loss.
  28. 28. The Environmental Technology Center at Sonoma State University
  29. 29. Passive Solar Design Principle #1:Think about where the sun is going to be.
  30. 30. from Miller, Living in the Environment
  31. 31. Note different scales for power radiated!
  32. 32. Thermal IR
  33. 33. Passive Solar Design Principle #2:Remember conduction, convection and radiative heat transfer.
  34. 34. Q = m c ∆TQ is amount of heat storedm is massc is specific heat∆T is temperature difference before/after
  35. 35. Outside and Inside Temperatures 100 90Degrees Fahrenheit 80 70 60 50 40 30 TEMP OUSTIDE 20 TEMP INSIDE 10 0 12:00 6:00 AM 12:00 6:00 PM 12:00 6:00 AM 12:00 6:00 PM 12:00 6:00 AM 12:00 6:00 PM 12:00 6:00 AM 12:00 6:00 PM 12:00 6:00 AM AM PM AM PM AM PM AM PM AM 06/27/01 to 07/01/01
  36. 36. Passive Solar Design Principle #3:Store warmth or coolth in thermal mass.
  37. 37. R-value: thermal resistanceU-value: thermal conductance, R = 1/U
  38. 38. Heat flow example:R-20 wallU = 0.05 Btu/h-ft2-oFArea = 100 ft2∆T = 30oFWhat is the rate of heat loss?Q = U A ∆T = (0.05 Btu/h-ft2-oF) × (100 ft2) × (30 oF) = 150 Btu/h
  39. 39. Note:U-value is weighted average of framing and area between framing.Any air gap between insulation & framing ruins the insulating effect.
  40. 40. Ballpark value for residential building envelope:UA = 500 Btu/h-oFHow much heating energy does it take?Convenient characterization of heating climate:“Degree-days” DD actually oF-d or ∆T-days
  41. 41. 443 Degree-Daysin San Francisco for themonth of January3001 Degree-Daysfor the whole yearFor example:300 days of ∆T = 10oF
  42. 42. UA = 500 Btu/h-oFHow much heating energy does it take?San Francisco heating climate: 3001 DDQ = U A ∆T-days × hours/day = (500 Btu/h-oF) × (3001 oF-d) × (24 h/d) = 36 million Btu = 360 therms
  43. 43. Passive Solar Design Principle #4:Insulate well.
  44. 44. SHGC: fraction of solar gain admittedthrough windowPerformance trade-off with U-valuefor solar heatingU-value: thermal conductanceU = 1/R0.35 Btu/hr-ft2-oF ≈ R-3
  45. 45. Passive Solar Design Principle #5:Be smart about windows.
  46. 46. Passive Solar Design Principle #1:Think about where the sun is going to be.#2Remember conduction, convection and radiative heat transfer.#3Store warmth or coolth in thermal mass.#4Insulate well.#5Be smart about windows.
  47. 47. Heat loss by conduction, convection and infrared radiationHeat gain bysolar radiation Building envelope
  48. 48. Heat gain by conduction, convection and infrared radiationHeat gain bysolar radiation
  49. 49. Heat loss by conduction, convection and infrared radiationHeat gain from naturalgas via hydronic floor
  50. 50. Question: Should I turn the heater off Heat loss by conduction,while I’m gone? convection and infrared radiation YES! Driven by temperature difference between inside and outside Replaces heat lost through envelope Heat gain from natural gas via hydronic floor
  51. 51. Basic principle for smart energy use in any building:Think of heat flow through the envelope.
  52. 52. Solar collectors for domestic hot water
  53. 53. Focusing with a parabolic mirror
  54. 54. If you use solar energy, yourchildren will be well-groomed, polite and gladlyhelp with chores.
  55. 55. Solar Thermal Power at Kramer Junction, CA Photo: PG&E
  56. 56. Photo: Pacific Gas & Electric
  57. 57. Vestas 1.8 MW 260’ height, 135’ radius www.tva.gov
  58. 58. Interesting constraints:Transmission infrastructureResource location, cooling waterEnergy storage capacityTemporal coordination
  59. 59. Drastic reductions of carbon emissionsThree investment strategies:Energy efficiencyplus• carbon capture All three are expensive, so cost• nuclear energy alone is not a decisive factor.• renewables
  60. 60. Image: IPCC
  61. 61. South Texas Project, Photo: www.nielsen-wurster.com
  62. 62. CCS: Carbon Capture and Storage or Carbon Capture and SequestrationProblematic issues:• sheer quantity of carbon• no inherent performance incentive• verification• permanence of disposal
  63. 63. Nuclear energyProblematic issues:• “vulnerability to human frailty, incl. stupidity and malice” (John Holdren)• slow, committing infrastructure investment• ethical concerns
  64. 64. Portfolio of renewable energy resourcesProblematic issues:• spatial and temporal constraints on energy availability• requires sophisticated, integrated planningIn my opinion, these are the most readily solvable problems.
  65. 65. Pacific Gas & Electric, 1989
  66. 66. Exclusion zone radius 18 km, area 109 m2Incident solar radiation 1000 W/m2at conversion efficiency 0.1could generate 108 kW or 100 GW of solar powerat capacity factor 0.2 would produce 5% of U.S. electric energy

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