# Cumulative Energy Demand and Carbon Footprint of the Greenhouse Cultivation System
## 1 Introduction  
Horticulture uses a significant amount of energy, contributing to greenhouse gas emissions and global warming [1]. Greenhouses (GH) are among the most energy-absorbing structures, mainly due to the thermal efficiency of the envelope. Energy savings can be achieved through the use of multi-layer roof panels or movable insulating screens. The heat transfer coefficient for greenhouse envelopes [2] without energy-saving measures is many times higher than for envelopes in typical buildings. In addition to typical energy-saving solutions in GHs, it is essential to pay attention to the possibility of using new covering materials integrated with photovoltaic technology. They have been extensively studied to improve light transmission and capture the solar energy needed to produce electricity [3]. The choice of materials is made depending on the type of cultivation carried out and the geographical location of the facility. Physical properties are crucial but economic factors, and environmental sustainability must always be considered [4]. Very promising materials for shading GHs are semi-transparent organic photovoltaic cells with strong absorption of near-infrared radiation (NIR) and visible light transmittance favourable to crop cultivation [5]. Renewable sources are taken into account in newly designed greenhouses instead of fossil fuels. An interesting option is the use of heat pumps. The advantage of heat pumps is the possibility of heating or cooling the GH, depending on the current requirements of the facility. The application of heat pumps is conditioned by the availability of a lower heat source at appropriate parameters [6, 7]. Another option is to power the GH with a cogproduces heat and electricity simultaneously [8]. In any case, GH energy efficiency issues, due to their lightweight construction and inefficient operation, have to be aimed at reducing energy consumption and carbon footprint [9]. According to [10], there is great potential for reducing the environmental footprint of horticultural systems, especially in heated GHs [11]. Research on this issue, based on the life cycle assessment (LCA) method, focuses mainly on the production of tomatoes and less frequently on ornamental plants and cut flowers. [PERSON] et al. have analysed tomato cultivation in Greece and Germany [1]. The considered GHs were fuelled with natural gas and pellet, respectively. [PERSON] et al. have assessed the environmental impact of tomato cultivation in France [12]. Year-round production in GH heated with natural gas was compared to seasonal cultivation under unheated plastic tunnels. In the paper [13], the LCA method was used to compare tomato production in an unheated GH located in Morocco with output in a natural gas-heated GH in France. [PERSON] et al. developed the tool to perform LCA analysis, and subsequently, they studied the production of tomatoes (in Spain, Hungary and the Netherlands) and cut roses cultivation in the Netherlands [11; 12; 13; 14]. In turn, [PERSON] and [PERSON] evaluated the organic cultivation of tomatoes in Sweden. SimaPro 8.2 software was used for the calculations [15]. In Poland, however, the environmental footprint of GH cultivation has not previously been studied. The climate in Poland can be described as transitional, with hot summers and cold winters with the possibility of intense snowfall. In line with Directive 2008/50/EC of the European Parliament and of the Council of 21 May 2008 on ambient air quality and cleaner air for Europe [16], and in order to protect human health and the environment as a whole, it is particularly important to combat pollutant emissions at their source. At the same time, it is essential to identify and implement the most effective emission reduction measures at local, national and community levels. The IPCC report [17] identifies technologies and practices that can reduce greenhouse gas emissions in key sectors of the economy.