VIS- COMMERCIAL APPLICATIONS
Glass greenhouses – still at the mercy of weather
Maximizing of plant growth requires the levels of temperature, carbon dioxide and light being optimized continuously. Optimal conditions are very hard to maintain year-round in the poorly insulated glass greenhouses, because the varying weather outside affects the greenhouse climate making it unstable. For example, during warmer months, too high of a temperature becomes a problem. Rising temperatures inside the greenhouses force the farmers to open up the roof panels to bring down the temperatures. This makes it impossible to keep up the carbon dioxide levels at optimum and this is detrimental to the growth of the plants. In cucumber farming, for example, the size of the crops in the summer are only half of the size of winter crops.
What is a Plant Factory?
Plant Factory with artificial lightning (PFAL).
Completely closed system for indoor farming without sunlight
Utilization of energy-efficient LED technology
Possibility to optimize the growing conditions: 1) good thermal insulation leads to balanced level of temperature 2) minimization of air exchange to keep the carbon dioxide levels at optimum
Vertical growing: multiple layers of plants stacked on top of each other
Effective use of resources (for example water and carbon dioxide)
Profitability of Plant Factories is continuously improving with the technological development of LED technology
Plant Factories today are often built out of unecological and expensive materials like concrete and steel
Plant Factories are already in use in Japan, China and USA
VIS Plant Factory provides extra heat
Thanks to its insulation capabilities, no excess heat besides the one produced by artificial lightning is needed in the VIS Plant Factory. As a matter of fact, VIS Plant Factory produces excess heat even on the coldest winter days. This excess heat can be utilized in the heating of nearby buildings or glass greenhouses. During the project, the VIS team will also explore the possibility of connecting VIS Plant Factories to the heating district system.
VIS Technology in Plant Factories
The conditions inside a greenhouse are challenging for insulation materials: the relative humidity inside the growth space can rise to over 80 % and at the same time, the temperature difference between the inside and outside air can be over 50 Celsius. Thanks to the vacuum drying technique, VIS thrives even in these conditions meaning more focus can be put on designing the elements to be maximally cost effective, ecological and easy to manufacture. The VIS elements are also designed to have a long life cycle and minimal maintenance. Thanks to its modularity, VIS elements are easy to transport to and assemble at the construction site and VIS Plant Factors can be easily expanded later on.
Energy efficiency and more crop with VIS Plant Factory
As stated before, In the VIS Plant Factory, no extra heating is needed besides the heat produced by the artificial lights. This means that considerable amounts of energy is saved compared to traditional glass greenhouses even when taking into account the energy used by the artificial lightning. In addition to saving energy, VIS Plant Factory also increases the amount of crop. This is based on the fact that the most critical factors for plant growth, such as light, temperature and carbon dioxide, are optimal year-round.
Stability and predictability
Extreme weather phenomena cause problems in glass greenhouses and bring unpredictability to the cultivation business. For example In the summer of 2018 in Finland, a long period of heat caused partially destroyed crops in glass greenhouses. In the VIS Plant Factory such hardships can be avoided thanks to the closed system and superior insulation solution and the consistency that comes with it greatly improves the stability and thus the predictability of the business.
Solar panels at the rooftop
Even though VIS Plant Factory does not directly utilize sunlight, the advancement of solar panel technology has made it profitable to take advantage of the sun. A significant amount of summers’ energy need can be produced with solar energy by installing solar panels to the roof of the plant factory and by directly using the electricity provided by the panels to power up the LEDs.
Vertical farming is a cultivation technique where multiple tiers of cultures are stacked on top of each other inside the plant factory. For example in Japanese plant factories, up to 15 tiers of lettuce are grown vertically, greatly enhancing the efficacy of land usage. When considering that each tier in a plant factory produces more crop than a similar-sized area in greenhouses or outdoors, a 15 tier Plant Factory efficacy per square meter is tens of times higher than in a greenhouse and over 100 times higher than in open field cultivation. More efficient land use makes it possible to bring the food production closer to cities where most of the consumers and workforce live in order to cut down logistical cost. More efficient land usage also means that parts of the land area currently occupied by fields can be turned into forests to help capture carbon dioxide and battle the climate change.
VIS Element in thermal energy storages
Efficient seasonal thermal energy solutions (STES) help energy supply and demand meet. As the production of solar and wind energy grows quickly, the volatility of the energy production rises and leads to situations when oversupply occurs. When this happens, the price of electricity plummets and some of the produced energy is dumped. During these moments of over-supply, electricity can be transformed into heat energy and stored into large water tanks. Well-insulated STES’s have minimal thermal losses meaning that the energy can be conserved in storage until there is a strong demand for heating. The energy stored in the hot water tanks is then distributed to the consumers using the district heating system. The current thermal energy storage solutions rely on expensive materials and have problems with scalability. Thanks to its durability, cost effectiveness and scalability, VIS technology could be utilized in large scale, energy and cost efficient STES solutions.