Vertical indoor farming (VIF) is recognized as a resilient production method, however, its environmental performance is significantly limited by electricity demand. To provide experimentally validated evidence for fruiting crops, this study combines cultivation data from chili pepper grown at two photosynthetic photon flux densities (250 and 500 μmol m-2 s-1) in a VIF container with a life cycle assessment of three distinct energy supply scenarios. Doubling the light intensity raised annual dry yield by 57% to 3.1 kgDW m-2 a-1 but decreased light-use efficiency by 27%. System-level energy and water use remained similar across treatments at 922 kWh kgDW-1 and 14 L kgDW-1 respectively. With a fossil-based electricity mix, climate impact reached 74 kg CO2-eq kgFW-1, primarily due to lighting and cooling. Adjusting the light intensity or expanding the cultivation area within the VIF container only marginally reduced this impact. In contrast, utilizing renewable electricity with industrial waste-heat cooling reduced the impact to 3.9 kg CO2-eq kgFW-1, comparable to upper range values reported for tomato high-tech greenhouse systems. These findings demonstrate that the environmental performance of fruiting-crop vertical farms is mainly determined by the energy source rather than cultivation intensity or layout, underscoring the importance of integrating energy systems to improve sustainability outcomes.
Capsaicinoids, biosynthesized in pepper fruits (Capsicum annuum), are valuable compounds with diverse industrial applications. Their consistent production is essential but influenced by environmental factors such as light intensity and spectrum. Vertical indoor farming (VIF) systems offer precise environmental control over growing conditions, especially light, yet high energy costs often necessitate reduced light intensities. While peppers are light-demanding plants, their integration into VIF systems requires a balance between energy input and crop performance. To evaluate the feasibility of cultivating Capsicum annuum under energy-saving conditions, we investigated the effects of two reduced light intensities (250 / 500 µmol m⁻² s⁻¹) on fruit yield and quality across two chili pepper cultivars and one bell pepper in VIF conditions. Additionally, we assessed whether supplemental UV-A exposure at 500 µmol m⁻² s⁻¹ could enhance capsaicinoid accumulation.Capsaicinoid content per unit dry fruit mass was not significantly affected by light intensity or UV-A as main effects. However, a significant interaction between cultivar and treatment indicated genotype-specific responses. Medium light intensity (500 µmol m⁻² s⁻¹) significantly increased net photosynthesis and fruit number, resulting in 33–57 % higher dry fruit yield (12.5–29.2 gDW plant⁻¹) compared to the lower intensity (250 µmol m⁻² s⁻¹), and led to a corresponding increase in capsaicinoid yield per area, depending on cultivar. Light levels of 500 µmol m⁻² s⁻¹ are necessary to maximize yield and capsaicinoid output in VIF, while cultivar selection plays a critical role in determining compound accumulation.
Vertical Indoor Farming (VIF) offers a potential for high-quality strawberry production, but resource efficiency data still need to be provided. Three strawberry cultivars with different fruiting characteristics, one Ever-bearing cultivar and two June-bearing (high-yielding and an old, traditional) cultivars, and two light treatments were investigated: artificial white LED light with an additional 2% UVA (365 nm) and white LED light alone. The Ever-bearing cultivar demonstrated significantly higher efficiencies for surface use efficiency (SUE) of 15.2 kg fresh weight m-2 a-1, water use efficiency (WUE) of 291 g fresh weight l-1, and energy use efficiency (EUE) of 10.6 g fresh weight kWh-1, due to a high harvest index of up to0.8 and a low proportion of non-marketable fruit. However, the total energy demand of a container VIF is high, with 4.4-6.4 kWh m-2 d-1. Additional UVA radiation did not significantly alter the Ever-bearing cultivar’s performance. At the same time, multiple harvests and a low proportion of non-marketable fruits led to a higher cumulative yield and increased efficiency, making it a promising choice for strawberry cultivation in VIF.
Plant production in indoor farming systems offers significant advantages compared to open field orgreenhouse production systems. Especially in terms of quality and the ability for automation the system is superior to the conventional production systems. Concerning resource consumption indoor farming has considerable advantages in regard to water consumption and the use of pesticides.The main disadvantage is the high consumption of electrical energy. Taking advantage of the specific benefits or eliminating the disadvantages, for example by using renewable energies, different potentials and fields of application for indoorfarming arise.The paper outlines the potentials and future fields of application of indoor farming considering the specific differences to conventional production systems related to resource consumption, quality and automation.
Climate change and increasing global urbanization accelerate the expansion of protected cultivation systems. However, certain dependences to external weather conditions remain even in modern greenhouses. Indoor vertical farming, on the other hand, pursues complete inde-pendence from external weather conditions with the aim for highly accurate control of all crop parameters. Particularly with regard to the advancing climate change and the need for sustainable resource consumption, there are clear advantages due to the year-round and independent cultivation of plants and raw materials under optimal conditions. The complexity in the optimal networking of the plant-technology systems offers intensive development opportunities for dig-itization and interdisciplinary collaboration.
Indoor vertical farming offers great opportunities regarding a sustainable and consistent production of high-quality herbs and raw materials all year round for the perfume, chemical, or food industry. Cultivation takes place in an enclosed structure, operating predominantly independent from external conditions in multi-layer systems equipped with artificial lighting, enabling extremely high resource use efficiencies with a simultaneous increase in yield. On the other hand, field production in terms of plant quality and harvesting times is highly influenced by environmental conditions, making it difficult to maintain homogenous raw material qualities throughout the year. To show how different light qualities affect the overall efficiency and quality of Origanum majorana grown in an indoor farm, the resource consumption, yield, and cultivation time as well as the essential oil quantity was analyzed, and the efficiencies in terms of energy and land use efficiency calculated. The experimental setup clearly demonstrated that the yield regarding fresh as well as dry matter and oil content was comparable to one square meter of open field production. Based on this, the multi-layer system and the noticeable lowered growth period result in a significantly higher area efficiency compared to the open field, leading to a potential increase of annual yields of dried leave weight and oil contents by up to 21 times. It was also shown that a white spectrum (W) showed similar influence on plant growth and yield as a spectrum consisting of blue and red (B/R). Nevertheless, the LED treatment W did show higher light use efficiencies as well as a better working conditions inside the cultivation chamber. By an integration of indoor vertical farming into existing industrial processes, new and innovative opportunities for a flexible and low-risk supply chain seem feasible and according to German food industry meet the interests of existing stakeholders.
More
Publications
Ivonne Wittmann,
Nicolas Mauser,
Eleonora Itri,
Heike Susanne Mempel
Development of an indoor farming cultivation process for Rhodiola rosea, using an aeroponic and deep-water irrigation method (2022) 31. International Horticultural Congress (IHC2022); International Symposium on advances in Vertical Farming .
Heike Susanne Mempel,
Ivonne Wittmann,
Julian Hecht,
Alexander Kunze
Influence of different light spectra on growth and quality of Rosmarinus officinalis cultivars in a deep- water vertical indoor farming system (2022) 31. International Horticultural Congress (IHC2022): International Symposium on Advances in Vertical Farming .
Ivonne Wittmann,
Heike Susanne Mempel
Pulsed light − optimal ratio between yield and energy reduction (2022)
Heinz-Josef Schmitz,
Ivonne Wittmann,
Dieter Lohr,
Elke Meinken
Extensive green roofs are a key component of urban water management in the future. On the one hand, they should mitigate urban heat islands, for which evapotranspiration has to be maximized, and on the other hand, they are supposed to reduce the risk of urban floods after heavy precipitation events. To achieve these goals, an exact measurement of the water supply status is necessary. In arable soils as well as in organic growing media, dielectric sensors are widely common. However, there is only little knowledge about the suitability of this kind of sensors for mineral and coarse-textured substrates used for extensive green roofs. In the current research four dielectric sensors (EC-5, 10 HS, SMT 100 and Aquaflex TR) were tested using five different green roof substrates. The five substrates were filled in plastic boxes of 80 x 60 cm. Substrate height was 15 cm and the four sensors were placed at half height. Afterwards, white lupine was sown and cultivated up to a height of about 30 cm. For testing the sensors, the substrates were saturated with water and then they have been left to dry out until plants show severe signs of wilt. During dry out, the sensor signals as well as the weight of the boxes were recorded automatically every five minutes. For each substrate six consecutive drying cycles were done. With exception of the Aquaflex TR, for all sensors output signals were closely linear correlated to the weight loss and signal ranges were comparable for the six drying cycles. However, significant differences in output signals of the sensors between the five tested substrates were observed. This indicates a need for substrate specific calibrations. The relation between the output signal of the Aquaflex TR and the weight loss was not linear, but also reproducible and suitable to assess water supply status of plants.
Einfluss des Belichtungs- und Kultursystems auf den Wuchs und weitere physiologische Paramater von Solanum lycopersicum (2021) Annual Conference DGG and BHGL 09.03.2021, Stuttgart (online), Germany .
Ivonne Wittmann,
S. Pfeil,
Elke Meinken
Auswirkung von Entfettung und Hitzebehandlung auf das N-Freisetzungsverhalten von Schafwolle (2018) Poster auf der 52. Gartenbauwissenschaftlichen Jahrestagung der DGG und des BHGL, 28.02.-03.03.2018, Geisenheim .
Magazine articles
Heidi Heuberger,
Andreé Hamm,
Sofie Gawronski,
Ivonne Wittmann,
Heike Susanne Mempel,
Fred Eickmeyer,
Susanne Wöster,
Joachim Müller,
Thomas Hannus,
Andrea Krähmer,
Georg Maier
Heidi Heuberger,
Andreé Hamm,
Sofie Gawronski,
Ivonne Wittmann,
Heike Susanne Mempel,
Fred Eickmeyer,
Susanne Wöster,
Joachim Müller,
Thomas Hannus,
Andrea Krähmer,
Georg Maier
Informieren - Diskutieren - Netzwerken - Neues Planen (2023) Aus der Praxis für die Praxis, 9. Tagung für Arznei- und Gewürzpflanzenforschung 2023 in Freising 28 (1), S. 24-35.
Ivonne Wittmann,
Nicolas Mauser,
Eleonora Itri,
Heike Susanne Mempel
Several lighting strategies in an indoor farm are compared regarding the annual electrical energy consumption. Based on measurements of the energy consumption during one experiment, conducted inside the indoor farm at the HSWT, an energy balancing model was calibrated and subsequently validated by a second experiment. The model was then used to calculate the potential reduction of the annual electrical energy consumption concerning several different lighting strategies. Furthermore, different settings of temperature set points and the impact of an optimized heat transfer coefficient as well as a more efficient performance for heating and cooling are considered. The measured and the modeled energy consumption and the values regained by the model showed a high regression coefficient (R2=0.936). The prediction of the energy consumption during the second experiment was also possible (R2=0.738) with a total difference to the measured consumption of 29.1 kWh. Regarding the given technical settings of the indoor farm, the annual electrical energy consumption can be reduced by up to 16% by an adjustment of the temperature strategy while reaching a similar yield. By assuming an optimized technical setting, the relevance of the lighting strategy increased significantly. Based upon this an annual reduction of the electrical energy consumption of up to 21% seemed conceivable.
More
Talks and presentations
Ivonne Wittmann
Indoor Vertical Farming - Applied Science Centre for Smart Indoor Farming (2023) Vortrag auf der IPM Essen, Januar 2023 .
Ivonne Wittmann,
Heike Susanne Mempel
Fruit vegetables in indoor farming – potential of chili pepper production (2022) 31. International Horticultural Congress (IHC2022): International Symposium on Advances in Vertical Farming .
In dem Projekt sollen hydroponische Kulturverfahren für Schnittblumen und Schnittgrün in Richtung einer nachhaltigen, umweltgerechten und regionalen Produktion weiterentwickelt werden. Die …
KurzbeschreibungDas Forschungsvorhaben setzt sich zum Ziel, eine bioökonomische Optimierung der Ressourceneffizienz beim Anbau von Pflanzen in Indoor Vertical Farmen (IVF) durch die Integration der …
We use cookies. Some are necessary for the website to function, others help us to improve the website. To meet our own data protection requirements, we only collect anonymised user data with "Matomo". To make our website more appealing to you, we also integrate external content from our social media channels.