1. Odum’s Energy Ecology
& Green Houses
Local and Ecological

2. Outline
 Odum Energy, Ecology  Heat Gain and Loss
and Economics  Energy Value
 Food Supply  Efficiency
 Greenhouses  Passive Solar Design
 Growth Systems  Orientation
 Ecology of  Recap: Importance of
Greenhouses Growing Local
 Energy in Greenhouses  Living Building
Examples

3. Odum’s Energy Ecology
 Growth Priming:
 Favors economic vitality
 Quality Vs. Quantity
 Reduction of subsidies
 Quality of Life
 From steady state periods
 Net Output Richer than
Input
 Solar Conversion
Necessary
 Simpler Agriculture as a
Primary Solution

4. Applied to Food Supply
 Food = Basis for Society
 Quality of Energy:
 Stability and Growth
 Vitality of Food
 Growth Materials
 Quality of Life:
 More Time with People
 Application of Purpose

5. Food Supply Considerations
 Human Population
 Estimated 9 billion in 2050 (6.6 billion in 2008)
 2/3 Expected to be Urban Dwellers
 Global Warming
 Influence
 Food supply
 Agriculture systems
 Arable land
 Influences Water Supply
 Needs to increase clean supply
 Needs to increase availability and distribution

6. A Look at Green Houses
 Human and Natural Ecology Combined
 Local Energy Capture and Storage
 Input Energy Stored for Output Energy Use
 Local Energy Generation and Savings
 Uses Natural Processes and Natural Storage/Blocking
 Carbon and GHG Neutrality: Possible!
 Community Based Designed
 Based on need, and available resources
 Enhance Food Security
 Adaptable
 Efficient
 Automation possible

7. Types of Growth Systems
 Mono Culture
 Polyculture
 Biodynamic
 Hydroponics
 Aquaculture
 Algae for Energy
Growth

8. Ecology of Green Houses
 Incorporate with Waste Streams or Algae
Culture for Nutrient Enhancement
 Create ‘Green Space’ in Office Space
 Reduce Building Energy Needs
 Reduce Footprint of Greenhouses and Food
Supply
 Reduce Nutrient Runoff
 Through Monitoring

9. Energy in Greenhouses
 Energy from our environments
 Continuous and Renewed
 Solar, Organic, Natural Gas*, Water, Wind, Wood
 Stored
 Coal and Fossil Fuels, Natural Gas*, Nuclear
 In Ecology:
 Where continuous energy creates/generates stored energy
 Smart energy use is the lower energy ‘cost’ to produce the
same stored energy and/or energy output
 70-80% Used for Heating; 10-15% for Electricity [2]

10. Heat Gain & Loss
 Conduction
 Heat conducted through materials
 U-value – Btu/(hr-ºF-sq.ft.)
 Convection
 Heat exchange between moving
fluid (air) and solid surfaces
 Radiation
 Heat transfer between two bodies
without direct contact or transport
medium
 Sunlight
 Air Leakage/Infiltration
 Exchange of interior and exterior air
through small leaks and holes.

11. Increasing Energy Value
 Growth Versus and Towards Stability
 Reduce inefficiency of energy growth process
 Reduce Dependence on Fuel subsidies
 Reduce Use of Non-Renewals
 Reduce Pollution
 Increase Output Recycling
 Increase Efficiency of Current Systems
 Reduce outputs for maintenance and general operation.

12. Enhancing Efficiency
 Stand alone
 Isolated growing conditions
 Include lots of plants to heat
 Natural ventilation
 Opening Side Walls or Top Windows
 1.7-1.8 – heat loss area to floor area (3000sq. ft.)
 Materials selection
 Water Collection/ Indoor Storage
 Color Selection
 Orientation

13. Passive Solar Design
[3]

14. Passive Solar Design (con’t)

15. Greenhouse: Passive Solar Design
Thermal Mass
(BTU/sqft/Fo)
Brick 24
Concrete 35
Earth 20
Sand 22
Steel 59
Stone 35
Water 63
Wood 10.6
Attached greenhouse:
2.5 gallons per sq. ft. of south facing glazing area for cool climates (4 month winters)
2 gallons per sq. ft. of south facing glazing area for temperate climates (3 month winters)
1 gallon per sq. ft. of south facing glazing area for warmer climates (2 month winters)
Free standing greenhouse:
3 gallons per sq. ft. of south facing glazing area for cool climates (4 month winters)
2.5 gallons per sq. ft. of south facing glazing for temperate climates (3 month winters)
2 gallon per sq. ft. of south facing glazing for warmer climates (2 month winters)

16. Sample R and U Values
Polycarbonate 6mm quad wall R = 1.79
Polycarbonate 8mm quad wall R = 2.13
Polycarbonate 16mm triple wall R = 2.5
Polycarbonate 8mm triple wall R = 2.0-2.1
Polycarbonate 8mm double wall R = 1.6
Acrylic double wall R = 1.82
Glass double layer R = 1.5 – 2.0
Glass double layer low-e R = 2.5
Glass triple layer 1 / 4 “ ( 0.6 cm) air space R = 2.13
Fiberglass glazing- single layer R = .83
Polyethylene Double 5mil film R = 1.5
Polyethylene Double 6mil film R = 1.7
Polyethylene single film R = 0.87
6 inches (15 cm) of fiberglass bat insulation R = 19.0
Polystyrene (styrofoam) 1 inch (2.5 cm) thick R = 4.0

17. Orientation
 East/West to Maximize Winter Sunlight
 Incorporate Cooling Sections for Air Flow
 Moveable Gutter Overhangs
[6] [3]

18. Increase Energy Value of Food
 Grown in biodynamic, or polyculture systems
 Grow and Buy Organic
 Process By Hand
 Picked When Ripe Food
 Eat Fresh
 Soil Enhancement

19. External Greenhouse Example:
Vertical Wall Green House
 Increased Food Supply
 Hydroponics
 Double-Skin Facades
 Reduce Maintenance
 Provide Shade
 Air Treatment
 Evaporative
Cooling
 Reduced Costs
 Mitigation
 Insulation

20. BioMachine: Buildings of Future
 Incorporate Automated Systems
 Clean Air
 Enhance Nutrients
 Irrigation Supply and Water Management
 Local Harvesting
 Solar Panels
 Solar Thermal
 Passive Heating and Cooling

21. Conclusions
 Human Ecological Incorporation
 Total Waste and Energy Stream
Considerations
 Reduced Need for Energy
 Increase Food Supply and Security
 Adaptability and Self Design

22. References
[1] - HT Odum- Energy Ecology and Economics
[2] Sanford, Scott; Energy Conservation for Greenhouses;
http://www.uwex.edu/energy/pubs/GreenhouseEC_SAREApril2010.pdf
[3] Sethi, V.P.; Survey and evaluation of heating technologies for worldwide agriculture
greenhouse applications; 2010
[4] Sethi, V.P. ; Experimental and economic study of a greenhouse thermal control system using
aquifer water; 2007
[5] Theodore Caplow; Vertically Integrated Greenhouse: Realizing the Ecological Benefits of
Urban Food Production; Ecocity World Summit 2008 Proceedings; 2008
[6] David Roper; Solar Greenhouses; http://www.roperld.com/science/solargreenhouses.htm