Wageningen UR University in The Netherlands provides access to cutting edge greenhouse technology worldwide. Story by CHRISTINE BROWN-PAUL
A recent issue of PH&G (August, Issue 46) looked at how an innovative new greenhouse project is a joint initiative between the University of Western Sydney (UWS) and Horticulture Australia Limited (HAL) in close cooperation with Wageningen UR University in The Netherlands.
Wageningen UR Greenhouse Horticulture will also collaborate on research in the field of horticultural production (plant sciences: climate and crop physiology interaction, climate and pest and disease interaction, water use efficiency and salinity effects; greenhouse climate and crop modelling; economics).
The greenhouse horticultural industry is fast developing in Australia. Several new large vegetable production sites have started their operation during the last years, some of them with Dutch technology. Commercial producers want to be facilitated with scientific knowledge and research conducted in comparable modern facilities under Australian climatic conditions. The new UWS high-tech greenhouse research facility is expected to fill that gap.
Wageningen UR Greenhouse Horticulture has an equivalent type of research facility in The Netherlands and is the cooperation partner in the Australian project. The research institute will help UWS to design the new greenhouse facility by using their greenhouse design models and experience.
At Wageningen UR, Dr Sjaak Bakker has expertise in designing and developing energy conservative greenhouses and greenhouse environment—crop response interactions. At present, he is manager of the newly formed Business Unit Wageningen UR Greenhouse Horticulture. Within this new unit, the Greenhouse Technology Group, the former PPO Greenhouse Horticulture and the cropping systems department of Plant Research International are brought together with research facilities in both Wageningen and Bleiswijk.
“Wageningen UR Greenhouse Horticulture has an excellent reputation abroad and is familiar with local possibilities and challenges in covered cultivation in other regions,” says Dr Bakker.
“This makes us an attractive partner for parties in The Netherlands and abroad when it comes to investigating possibilities for establishing sustainable and competitive greenhouse horticulture businesses and marketing innovative technologies.
“We engage in local research, adaptive greenhouse design, and capacity building; and we are constantly working to strengthen our reputation and our position abroad, in wealthy regions such as the Middle East as well as in developing regions such as in Africa and Asia,” Dr Bakker says.
In The Netherlands, Wageningen UR Greenhouse Horticulture is dedicated to innovating for and with the greenhouse horticulture sector.
“In collaboration with the business and scientific communities and the government, we analyse issues relating to operational management and cultivation and translate them into application-oriented research and innovation procedures,” Dr Bakker says.
Wageningen UR is a collaboration between Wageningen University, Van Hall Larenstein School of Higher Professional Education, and the specialised former research institutes (DLO) of the Dutch Ministry of Agriculture. It has 5600 staff and more than 8500 students working to solve scientific, social and commercial problems in the field of life sciences and natural resources.
“Wageningen UR aims to make a real contribution to our quality of life,” notes its website.
“To us, quality of life means both an adequate supply of safe and healthy food and beverages, on the one hand, and the chance to live, work and play in a balanced ecosystem with a large variety of plants and animals,” says Dr. Bakker.
According to Dr Bakker, the majority of problems the institution tackles are current production challenges. By 2020, for example, they hope greenhouses will be energy sustainable without the need for fossil fuels.
“Nutrient recycling is a major thrust, as the industry is working towards completely closed systems with no leaching,” he says.
Labour-saving technology is another key initiative.
“Over the past 20 years, labour costs have doubled. A lot of our efforts are going into automation and robotics.
“Lighting is also important. But while it is important for crop production, there are growing concerns with light pollution from greenhouses. LEDs may be part of the solution, and extensive research is being carried out with them,” Dr Bakker says.
Wageningen UR University researchers are also looking at how excess heat from greenhouses can be directed to nearby residential communities.
“Most greenhouses (in The Netherlands) are close to urban areas,” said Dr. Bakker.
“All of our research is decided by a grower advisory board, which sets the priorities.
“Collaboration with Wageningen UR Greenhouse Horticulture allows horticultural bodies to exploit state-of-the-art knowledge and technology for the development of greenhouse production, demonstration sites and research facilities around the globe; greenhouses which are adapted to local climate conditions and market potentials. Our partners can be assured we will optimally use the technical possibilities worldwide while securing the local feasibility and success.”
Already for decades, Wageningen UR Greenhouse Horticulture has been one of the driving forces in research and technology development for greenhouse horticulture in The Netherlands.
“Our knowledge and experience on greenhouse cultivation of ornamental and vegetable crops is unique in the world,” Dr Bakker says.
“Together with growers and high-tech companies, we have developed new cultivation systems, climate control systems, revolutionary greenhouse cover materials and other innovations. The use of these applicable new technologies has made greenhouse horticulture of The Netherlands leading in the world.”
Wageningen Campus itself is one of the greenest, most sustainable knowledge centres in the world.
“This is something we want to keep because we believe that sustainability is vitally important. It is also the reason why we invest a large amount of energy in making our operations sustainable,” Dr Bakker says.
“This means that we: construct and furnish our buildings as sustainably as possible; consume as little energy as possible and generate our own green electricity using wind turbines; avoid creating waste and recycle as much as possible and; serve sustainably produced and packaged food in our restaurants and canteens.”
Exploiting produce markets
According to Dr Bakker, market demands vary throughout time and place.
“Our ambition is to allow our partners an optimal exploitation of these markets; export markets and markets close to the production site. Optimal production requires the right technology given the economic situation and expertise in crop production optimisation. To achieve this, we follow our ‘adaptive greenhouse production system design’ approach for production as well as other greenhouse facilities,” he says.
“Greenhouse sites with special functions, like research or demonstration, need a special touch to develop. We have shown to have that touch and have developed sites in several countries, e.g. Indonesia, Turkey, Malaysia and the Middle East. We develop optimally tailored sites, using teams, which are a clever combination of local experts, high-tech companies and our own top scientists.
Acquiring new technologies and market information is one step, being able to use the technology and the data to its limits is the next.
“We have trained numerous scientists and trainers/advisors of growers across the globe in a wide range of competencies,” Dr Bakker says.
“Understanding the growth of crops, the hardware and software of the greenhouses and the markets, allows growers to make a maximum profit and enables scientists to fully exploit costly greenhouses so as to carry out their research in an optimal way.”
Energy savings in the greenhouse
Writing in Chronica Horticulturae (Vol 49, Number 2, 2009), Dr Bakker describes how efficient use of energy in greenhouses has been subject of research and development since the first energy crisis in the early 1980s when the constriction in the supply of oil caused a significant increase in energy prices (Bakker et al., 2008).
“This spike in energy cost occurred again in 2008. Furthermore, the new European targets on reduction of CO2 emission have resulted in a renewed interest in innovative technologies to improve energy efficiency. The need for energy cost reduction is critical in the greenhouse industry since energy forms a substantial fraction of total production costs,” he says.
“For European conditions, it has been calculated that annual energy use for conditioning ranges from 10-30%, depending on the different regions, while the absolute use differs from 1900 MJ m-2 (Finland), to 1500 MJ m-2 (The Netherlands), and 500-1600 MJ m-2 (Southern France).
“The increase of production per unit of energy (energy efficiency) can be achieved by reduction of the energy use and/or improvement of production. In fact, all cultivation measures that increase the production, such as improved irrigation, better nutrition, pest and disease control, and better utilisation of the available greenhouse area, also improve energy efficiency,” Dr Bakker says.
According to Dr Bakker, focusing solely on energy efficiency without any focus on the absolute energy use may have unexpected (and undesired) effects from an environmental point of view.
“Even in Mediterranean areas, heating is used to obtain early production and a constant quantitative qualitative yield, leading on one hand to a higher energy efficiency, but at the same time also to a higher absolute energy use,” he says.
“Also improved environmental control (e.g. more CO2 supply, additional lighting), intensified production schemes (Boulard, 2001), and use of cooling systems to expand the growing period into months with high temperatures, all cause an increase in energy consumption (De Pascale and Maggio, 2004).
“The same holds for the Northern regions with respect to the use of artificial light up to very high levels (e.g. over 200 W m-2) in Finland (Olofsson et al., 2006) and over 100 W m-2 in The Netherland,” he says.
“The major challenge is to find ways that meet both needs: improved energy efficiency combined with an absolute reduction of the overall energy consumption and related CO2 emission of the greenhouse industry. In general, the same objectives hold for Mediterranean and Northern European regions: during fall/winter the objective is to maximise the radiation quantity (either from natural light or artificial light) and minimise the energy loss; during the spring/summer the objective is to reduce high temperatures.”
In The Netherlands, the target is even more ambitious than merely improved energy efficiency. From 2020 and on, says Dr Bakker, new greenhouses should operate almost without any fossil fuel and even should be “energy producing”.
“This ambitious goal is based on the idea that greenhouses are large solar collectors that collect almost 80% of all incoming solar radiation. For northwest European conditions, the yearly solar irradiation sum equals approximately 3.5 GJ m-2, which is equivalent to the combustion value of 100 m3 of natural gas (=100 NGE),” Dr Bakker says.
“Since the incoming solar radiation represents about twice the energy used in the greenhouse itself, this theoretically creates the possibility to use the greenhouse as a combined crop and heat producing system.”
To reach this ambitious goal, a research and development program has been started at Wageningen UR, under the name: Greenhouse as Energy Source.
“Although the ambitions are even higher, the steps to be taken in this development process are still the same as before: maximum use of solar energy, reduction of energy use in the greenhouse and replacement of fossil fuel by other sustainable sources,” Dr Bakker says.
Last year, the 5th Norwegian-Dutch seminar on ‘Energy saving in horticulture’ was held at the Wageningen University and Research Centre. A group of Norwegian researchers, students, lecturers and consultants visited Wageningen UR Greenhouse Horticulture in Wageningen and in Bleiswijk for a two-day knowledge exchange.
Seminars were held on the field of energy saving greenhouse concepts like insulating greenhouses or semi-closed greenhouses, modern temperature and humidity control strategies, dehumidification concepts, and the effect of diffuse light and LED light in crops including available technical solutions.
The seminars also covered innovations on early stress detection in crops, photosynthesis characteristics under low temperatures, and stomata functioning under high humidity levels. Information was shared in lectures as well as in visiting practical experiments. Ω
PH& September 2014 / Issue 147