# Cumulative Energy Demand and Carbon Footprint of the Greenhouse Cultivation System
## 2 Materials and Methods
The amount of non-renewable primary energy consumed by the greenhouse for heating purposes over an entire year was calculated using Equation (3):  
\[\mathrm{Q_{P}=w_{H}\cdot Q_{F}+w_{E}\cdot Q_{E,aux}}, \tag{3}\]  
where  
\(\mathrm{w_{i}}\)--primary non-renewable energy consumption factor for generation and supply of final energy carrier (or energy) to the interior of the greenhouse; \(\mathrm{w_{H}}\)--refers to the heat used for heating, \(\mathrm{w_{E}}\)--refers to electricity;  
\(\mathrm{Q_{E,aux}}\)--annual demand for final electricity used to drive auxiliary equipment of the heating system. Primary non-renewable energy consumption factors for fossil fuels, i.e., coal and natural gas, are 1.3 and 1.2, respectively, while for biomass, it is 0.2 (scenarios 3 and 4). It is assumed that the non-renewable primary energy consumption for electricity supplied through the national energy system amounts to 3.0 [31]. The amount of fuel needed to produce the final energy was determined by taking into account the LHV of coal, according to information obtained from the fuel supplier for the horticultural plant. Other parameters for coal and natural gas are in line with the national data [32], while the LHV and carbon dioxide emission factors were obtained from the National Centre for Emissions Management [33; 34], which, in turn, correspond to the IPCC guidelines [35] (Table 2). The Centre's emission factors are used to determine the fees for using the environment. Therefore, the analyses were based on national data on pollutant emissions. \begin{table}
\begin{tabular}{l c c c c c} \hline \hline
**Description** & \multicolumn{5}{c}{**Scenario**} \\  & **1** & **2** & **3** & **4** & \\ \cline{2-6}  & **Coal** & **Natural Gas** & **Wood Pellets** & **Wood Chips** & **Electricity** \\ \hline lower heating value (LHV) & & & & & \\
[M]\(\cdot\)kg\({}^{-1}\)] or * [M]\(\cdot\)m\({}^{-3}\)] & 21.71 & 36.62 * & 15.6 & 11.6 & - \\ carbon dioxide emission factor & & & & & \\
[kg CO\({}_{2}\) G]\({}^{-1}\)] or ** [kg\(\cdot\)MWh\({}^{-1}\)] & 94.94 & 55.43 & 112.0 & 100.0 & 778 ** \\ \hline \hline \end{tabular}  
* in \(\mathrm{MWh}\)\({}^{-3}\) for natural gas; ** in kg\(\mathrm{MWh}\)\({}^{-1}\) for electricity.  
\end{table} 
Table 2: The lower heating value (LHV) and carbon dioxide emission factor [32; 33; 34; 35]. According to the rules set out in the emission allowance trading scheme, CO2 emissions from biomass combustion are not included in the total emissions from fuel combustion. This is equivalent to using a zero-emission factor for biomass. In the analysis and discussion, the results obtained for scenarios 2 to 4 are compared with the reference scenario 1 (burning coal). The analysis is based on the LCA [36; 37] methodology used as a business assessment instrument that provides comparable research results when considering many of the GH environmental footprint issues. Energy and environmental analysis address the impact of energy carriers and air pollution. The CED and CF values are based on a continuously heated GH intended for growing plant flowers in pots. The use phase of GH is a fundamental process because it is only through its operation that the needs for which it was built are met. Previous publications indicate that the most visible factors are those influencing the CED and CF use phase, with the exception of design, fuel and electricity [1]. In line with the 2006 IPCC Guidelines, a national methodology for determining pollutant emissions was used whenever possible to obtain more accurate emission data. Two functional units (FU), defined as the number of potted plants during the annual cultivation cycle and the reference cultivation area of one square meter per year (land-based FU), were applied to determine the CED and CF values. The research has focused on determining the impact described by CF and CED. CF as a measure of the potential to generate the greenhouse effect enables conversion from emissions of other gases to the reference gas, i.e., carbon dioxide equivalent (CO2-eq).