# Enhancing biogas Plant Efficiency for the Production of Electrical and Thermal Energy
## 3 Results and Discussion
### The Objects and the Equipment
#### 3.4.8 The Gas Power Line and the Parts of the Gas Power Line
The digester heating system consists of horizontal plastic pipes made of cross-linked polyethylene that run along the outer circular wall of the digester, approx. 16 rows of pipes. Hot water for heating the digester is provided from a heat exchanger installed inside the \"CHP\" plant. The temperature of the water for heating the digester is about 40 \({}^{\circ}\)C and the estimated maximum heating capacity of the digester of this system is about 140 kW. The necessary amount of thermal energy for the heating of the substratum \(Q_{ps}\) is calculated as follows:  
\[Q_{ps}=m_{s}\cdot c_{ps}\cdot\Delta t \tag{1}\]  
where \(m_{s}\) represents the flow of the mass of the substratum, \(c_{ps}\) represents the specific thermal conductivity of the substratum, and \(\Delta t\) represents the difference between the temperature of the substrate in the digester and the entry raw material. Note: The balance is changed by the seasons and the months. The average monthly temperature is taken. Table 3 and Figure 6 show the thermal energy which is needed for the warming up of the digester. Key observations from Table 3 indicate that the entry temperature varies throughout the year, with the lowest values during the winter months (5.0 \({}^{\circ}\)C in January) and the highest values during the summer months (17.0 \({}^{\circ}\)C in July and August). Correspondingly, the temperature difference is highest in January (35.5 \({}^{\circ}\)C) and lowest in July and August (23.5 \({}^{\circ}\)C). Consequently, the necessary thermal energy (kW) is highest in January (87.5 kW) and lowest in July and August (57.9 kW). The monthly thermal energy requirement (kWh/month) follows the same trend, being highest in January (65,097 kWh) and lowest in August (43,092 kWh). Figure 6 visually represents the data provided in Table 3. It shows the monthly variation in the thermal energy required to heat the digester. The x-axis represents the months of the year from January to December, while the y-axis represents the thermal energy required in kWh/month. The graph highlights a peak in thermal energy requirement during the colder months (January) and a trough during the warmer months (July and August). This visual representation facilitates quick identification of the months with the highest and lowest energy requirements, aiding in easier planning and resource allocation for maintaining optimal digester temperatures throughout the year. The significant variation in thermal energy requirements underscores the need for effective insulation and possibly additional heating mechanisms during colder months to maintain the digester at the desired temperature. Understanding these variations allows for better energy management and cost planning, ensuring that sufficient resources are allocated for heating during the winter months. Maintaining a constant digester temperature is crucial for the efficiency of the anaerobic digestion process, and this analysis ensures that the plant can operate efficiently year-round. Overall, the analysis of Table 3 and Figure 6 provides valuable insights into the seasonal variations in thermal energy requirements for the digester. These insights are critical for optimizing the design and operation of the biogas plant, ultimately contributing to its overall efficiency and sustainability. The integration of optimized substrate selection and advanced digester heating techniques in our study has led to a measurable improvement in biogas production efficiency and yield. This demonstrates the practical application of our methodology in enhancing biogas plant performance. Our approach bridges the gap between theoretical research and practical implementation, showcasing tangible benefits in operational efficiency.