Patrick Romeijn, Production Manager at Anthura:
"Horticulture can play pioneering role in CO2 reduction"
Step 1 – Reduction of the energy demand
The guiding principles of the production facility at the Cyclamenweg are: a maximum reduction of the energy demand, a maximum climate control and an as high as possible energy efficiency.
Screens and isolation
In all cultivation areas three screens are installed; a below screen and a diaphragm screen that consists of two screens. Additionally, the greenhouse cover of all non-cultivation areas, including the loading docks and the processing areas (approximately 2 hectare), is equipped with insulating sandwich panels. The perimeter of the building is fitted with a corridor, that serves as a thick air gap of which the effect can be compared to that of double glass.
Closed greenhouse
Of the 10.3 ha of cultivation area, a surface of 2.8 ha has been arranged as a closed greenhouse. In these closed greenhouse departments, a film without ventilation holes has been installed, thus reducing the energy consumption even further.
Patrick Romeijn explains the sustainable design of the closed greenhouse: ”During cooling, we ‘harvest’ heat and store it in aquifers. When heating, the harvested heat is pumped from the aquifers and upgraded by the heat pumps. Then it is used to heat through the low-value temperature nets and the air conditioning units”.
By harvesting heat in the closed greenhouse during cooling and by reusing it for heating, the heat pump system provides about 27% of the total heat demand and we achieve a saving of approximately 22% of the total gas consumption.
“Over the last 8 years we have learned a lot from cultivating in a closed greenhouse. Thanks to the good results and the sustainable way of growing, we expect that the use of heat pump systems in combination with closed/conditioned greenhouse departments will only increase at our facilities.”
Step 2 – Use of energy from sustainable sources
For the electricity and heat production, Anthura has a Combined Heat and Power (CHP) of 3 MW at the Cyclamenweg. The CHP is now producing about 55% of the total electricity demand and provides approximately 38% of the total heat demand.
Anthura is connected to the Rotterdam heating network of the RoCa and can hence use the residual heat of the RoCa power plant. The RoCa residual heat fulfils now about 20% of the total heat demand. It is expected that in the coming years increasingly more suppliers of heat will appear; think, for example, of a residual heat supply from the port of Rotterdam, the waste-disposal organization of Rotterdam, but also geothermal heat.
Patrick: “We are looking at the long term and by using residual heat and the huge emergence of green electricity, the use of CHP will decrease. Part of the used green electricity will be generated by ourselves from solar or wind power."
Step 3 – The most efficient use of fossil fuels
The production facility at the Cyclamenweg has an energy connection with other Anthura facilities in Bleiswijk. This facility supplies the breeding sites with the required cooling capacity for the cooling and finishing of phalaenopsis, part of the heat and all electricity. With this heat, cold and electrical connection Anthura has its own energy cluster.
Patrick: “Within this cluster the demand for heat, cold and electricity complements one another. As we can choose from multiple efficient energy sources, we are able to optimize in each situation.”
About 15% of the heat demand is now produced by gas-fired boilers. This heat can also be replaced by heat from heating networks. A reliable CO2 supply is essential to obtain more heat from heating networks.
Patrick expects that a tighter regulation for the CO2 emission will lead to more CO2 providers for the horticultural sector, which will increase the sustainable use of CO2. According to him, the horticultural sector as a whole can play a pioneering role in achieving the target of the Energy Agreement for sustainable growth and the Climate Agreement of Paris.
Source: Anthura Unlimited