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
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