Agriculture Reference
In-Depth Information
30.0
Jun
Jul
27.5
25.0
Almeria-Spain
Aug
22.5
Amsterdam-The Netherlands
Continuously ventilation
and/or cooling
Jun
20.0
Jul
17.5
Aug
15.0
Dicontinuously
ventilation
Feb
12.5
Jan
10.0
Dec
7.5
Feb
5.0
Closed
2.5
Jan
Heating
Heating night
No heating
Dec
0.0
0.02.5
5.07.5
10.0 12.5 15.0 17.5 20.0 22.5 25.0 27.5 30.0
Mean air temperature (
o
C)
Fig. 10.10
The mean solar radiation vs. mean air temperature for Amsterdam (The Netherlands)
and Almeria (Spain). The climograph:
dotted lines
indicate border lines for different control action
in the greenhouse. (Source: Food and Agriculture Organization of the United Nations, Kittas et al.
2013
. Reproduced with permission)
sumption (Gruda et al.
2009
). The most feasible measures in cost-efficient energy
conservation were due to following measures (Table
10.1
):
Recently, the reduction of energy consumption using new covering materials,
double and triple thermal screens, climate control strategies, energy optimized cul-
tivation programs, and greenhouses as solar energy storage, are some of the new
development projects in the Netherlands (de gesloten kas: the closed greenhouse)
and Germany (ZINEG: the low-energy greenhouse). All these systematic tools to-
gether with the use of alternative and renewable energies, without using fossil fuels,
Table 10.1
Energy conservation measures in greenhouses. (Source: NN
2012b
)
Nr.
Type of saving
Saving potential (%)
1
Thermal screen
20-40
2
Sealing of vents and windows
10-20
3
Heating system
10-18
4
Optimization of boiler
10-15
5
Climate control
10-20
6
Better use of cultivation area/crop planning
10
7
Special insulation and glazing
7-10
8
Sensors
5-10
9
Irrigation
5-10
10
CO
2
—Fertilization
5
