Recent advancements in the energy performance of intelligent green houses: a case study

Abstract

According to the European Environment Agency, the agricultural sector consumes around 3% of the total energy consumed in the European Union and specifically 28.8 million tones of oil equivalent in 2016. Although between 2005 and 2016, the final energy consumption in the EU decreased in the fishing, agriculture and forestry sectors by 24.7 % the energy required in this sector is considered to have a significant contribution to the energy related policies of the EU. Greenhouses constitute a major energy consumer of the agricultural sector in the European Union. Although strictly speaking, greenhouses differ from buildings in several ways, such as the construction, the building systems and the use, the principles used to analyse the energy consumption of greenhouses, as well as the strategies to control their energy performance are quite similar with those of the building sector. This study aims to present the recent advancements in the analysis of the energy performance of greenhouses, with a special focus on next generation greenhouses, also known as intelligent greenhouses. The main energy consumption sources in greenhouses, as well as their normalized intensity is presented. State-of-the-art automations to control the energy performance of greenhouses, as well as intelligent systems used to achieve the required thermal conditions in greenhouses, such as automation systems, infrared heating and advanced covering materials are presented. The main challenges of the intelligent greenhouse sector, as well as the requirements for the development of new energy related standards for greenhouses are also discussed. The study concludes with the presentation of the energy performance of a greenhouse, considered as intelligent, of the Department of Agricultural Technology of the Technological Education Institute of Western Greece in Patras, Greece. Detailed data logging of the temperature and indoor conditions of an intelligent greenhouse are analysed and compared with regard to contemporary greenhouses, revealing and quantifying the potentials of this sector in the energy saving strategies of Greece and the EU.