Obtaining bench mark figures for production levels and consumables for three tomato greenhouse technology levels
Main Studied Key Factors are
- Three greenhouse technology: Low, Medium and High
- Two cultivars: Dafanis and Cluster (RZ)
- Water consumption for irrigation and cooling is about 88 liter/kg in Low-tech, 47 liter/kg in Medium Tech and 2.5 liter/kg in High Tech greenhouses.
- In Air Conditioning cooled greenhouse, 95% of the water transpired by the crop can be re-used, so almost no water loss
- Electricity consumption is 1.2 kWh/kg for Low-tech, 2.4 kWh/kg for Med-tech and 12 kWh/kg for High-tech greenhouses
- Hi-Tech greenhouses can only be economically viable at low electricity price (< 0.15 SAR/kWh) and or high costs for water (> 1 SAR per m³)
- High Tech greenhouse production is a capital-intensive production system that needs a high turnover and throughput to be economically relevant. Good arrangements with customers on price and quality are therefore crucial.
- The very dry outside air conditions in the Riyadh-region allow for good evaporative cooling. Despite the high outside temperature and radiation levels, pad and fan cooling provide a favorable inside climate for growing tomatoes.
- With the current water and electricity prices, from an economical point of view, a medium-tech greenhouse is the best option.