Post on 14-Jul-2020
transcript
The African Greenhouse
A design toolkit
Anne Elings, Wageningen UR Greenhouse Horticulture
November 26th, 2015; Promoting Innovation & Trade in Horticulture
Why a greenhouse? Tomatoes in Indonesia
Greenhouse Open field
The issue
What does the best greenhouse for Africa look like?
What does ‘the best’ mean?
Environmental sustainability
● Water use (efficiency)
● Energy use (efficiency)
Economic sustainability
● Production
● Investment costs
● Running costs
● Pay-back period
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2.9630.036 0.001
seas and oceans
ice caps
sweet water
clouds
The physical environment is very diverse
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Source:
http://upload.wikimedia.org/wikipedia/com
mons/ 5/58/Vegetation_Africa.png
Mediterranean
Desert
Semi-tropical to temperate climate
Highland tropical
Lowland tropical
Other environments are also diverse
Economic
● Costs
● Benefits
● Pay-back time
Social
● Knowledge, skills, capacities
● Gender
● more
Enabling
● Rules and legislation
● Electricity and water networks,
logistics
● more
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Options – greenhouse design
Greenhouse construction: metal, wood
Greenhouse cover: net, plastic, glass
Climate system: natural ventilation, circulation fans, misting, hosing, pad & fan, heating
Screens: shade, thermal, clay/sand
Energy: fossil, solar, thermal, wind
Water: rivers/lakes, rain, bore hole
Substrate: soil, pots + substrate, slabs
Fertigation system: manual, gravitation, sensors, computerized, recirculation
Crop protection: biological, chemical, integrated
Post-harvest 6
Options – production systems
Outdoor farming
Subsistence farming
Small to medium farms
Medium to large farms
Farms growing speciality crops
Urban and metropolitan horticulture
Agroparks
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Options – crop and cultivar
Strategic choice
Depends on:
● market demand and price
● climate
● skills and knowledge of staff and management
● availability of resources.
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The toolkit for adaptive greenhouse design
greenhouse
crop
finances
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Examples
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Algeria
Emirates
Malaysia + Ghana Mexico
Taiwan
Summary
Options can be made explicit
Informed choices are possible
Grower makes ultimate decision
crop
Light Temp CO2
Water nutrients
Pests diseases
Manage-ment