Hybrid, energy-efficient farming by combined greenhouse and vertical growth

HybriGrowth: Hybrid, energy-efficient farming by combined greenhouse and vertical growth HybriGrowth is a collaborative research project between SINTEF (SINTEF Energi, SINTEF Ocean and SINTEF Industry), two greenhouse companies (Viken and Snarum Gartneri), and the Norwegian Horticultural Growers Association. The project explores a novel hybrid, energy-efficient greenhouse concept that combines vertical and traditional greenhouse farming. Here, plants begin their growth in a vertical unit before being transferred to traditional greenhouses for the main and final growth stages. The aim is to assess how such solutions can increase productivity, improve resource efficiency, and promote more climate-friendly production in Norwegian horticulture. Vertical production systems have been installed at the two greenhouses and are connected to their existing greenhouse facilities. In this hybrid concept, young plants initially grow in the vertical systems for a few weeks before they are transferred to the traditional greenhouse sections for the final cultivation stages. This allows the plants to grow in a stable and controlled environment during their early and most vulnerable stage, while the traditional greenhouse provides better light conditions and more air circulation during the main growth phase. The hybrid greenhouses remain unique in Norway, and the concept has so far only been tested to a limited extent internationally, with a demonstration center in China and a company in the United States focused on decentralized lettuce production as the best-known examples. Viken and Snarum Gartneri serve as in-depth case studies in the project. A key challenge is the large amount of heat generated by LED lighting in the vertical growth systems, which requires efficient cooling to maintain optimal growing conditions. At the same time, this surplus heat provides an energy source that can be reused in the traditional greenhouse sections. Measuring equipment has been installed in the heat distribution system at Viken Gartneri to track energy flows from the on-site heat pump, electric boiler, and gas boiler. Operational data are systematically logged and used in simulation models, together with other technical inputs, showing that the surplus heat can cover a substantial share of the heating demand in the adjacent greenhouses, especially in the winter months. The models indicate that this can reduce the reliance on fossil fuels such as propane, reduce CO2 emissions, and lower the overall operational costs. The project also explores how integrated heat pumps can improve energy flows and how thermal energy storage can help balance the energy use in hybrid greenhouses. Ultimately, the project aims to demonstrate a sustainable concept for increased productivity and profitability in Norwegian greenhouses through energy-efficient operation and an optimized growth environment. Measurement data from Viken Gartneri have been used to estimate the heating and cooling demands of the hybrid facility. The calculations estimate an annual heating demand of about 2,400 MWh for the traditional greenhouse sections, while the annual cooling demand in the vertical section is around 1,200 MWh. Results from this study were presented at GreenSys2025 in Almería, Spain, in June 2025 in the talk “Hybrid greenhouses combining vertical farming with traditional greenhouse production.” A complementary study on greenhouse lighting, focusing on indoor vertical plant production, has revealed opportunities for new lighting solutions that could significantly reduce energy consumption. The project has also been profiled through several presentations, including at Gartner2024 in Lillestrøm, Norway, and a SINTEF blog post titled Hybrid greenhouses: Combining traditional greenhouse and vertical farming.

At Viken and Snarum greenhouses, vertical farming systems have already been installed in combination with their traditional greenhouse facilities. The hybrid farming facilities are unique in Norway, and the concept has been tested and analysed to a limited degree around the world. In HybriGrowth, the Viken and Snarum facilities will act as in-depth case studies, and the potential of hybrid farming systems will be investigated in detail. The main challenge today is that the artificial growth lights in the vertical farming systems generate large amount of heat, which calls both for efficient cooling and an improved recovery of the surplus heat. In the project, operational data from the hybrid greenhouses will be modelled and analysed in detail to optimise the use of waste heat from the vertical section for heating of the adjacent traditional greenhouse. Specific measures will be applied for optimised operation and energy savings, in addition to a minimal carbon footprint by a reduced use of fossil fuels. Systems with use of integrated heat pumps will be studied, together with the feasibility of thermal energy storage to reduce the overall energy consumption in the greenhouses. The aim is to demonstrate a sustainable concept for increased productivity and profitability in Norwegian greenhouses by energy-efficient operation and optimised control of the indoor growth conditions.