Abstract
In vertical greenhouse systems, abundant lighting generates significant surplus heat, presenting an opportunity for its utilization in other applications. This study focuses on a hybrid greenhouse in Norway, where the surplus heat from the vertical section of the greenhouse is used to heat the traditional horizontal greenhouse. The building simulation tool IDA ICE is used to estimate the amount of surplus heat in the vertical greenhouse, considering factors such as the construction, ventilation, lighting, and outdoor climatic conditions. The study period spans from December 21 to January 25 during the winter of 2023/2024. The evapotranspiration from plants was adjusted to maintain optimal thermal conditions within the vertical section. According to the model, the average daily heat removal during the period amounts to 3.61 kWh m‑2 day‑1, closely aligned with the measured value of 3.49 kWh m‑2 day‑1. Despite uncertainties stemming from limited and irregular data logging, as well as modeling simplifications, the model is considered to provide a reliable estimate of the available surplus heat.