# Strategic Resource Planning for Sustainable Biogas Integration in Hybrid Renewable Energy Systems
## 2 Materials and Methods
### Area and System Study  
Aras de los Olmos is a small rural municipality in the Valencian Community of Spain, with fewer than 400 residents. Located at the end of a 20 kV power line, the area has experienced frequent outages and issues with electricity reliability. The municipality offers ideal conditions for renewable energy implementation, with available land for constructingwind, solar, and biogas plants, supported by its economy, which heavily relies on livestock farming, providing ample biogas feedstock. With a drop of over 100 m, the nearby river also creates a suitable location for a hydroelectric plant. These factors make Aras de los Olmos an excellent candidate for developing a hybrid renewable energy system that combines PV, wind, hydro, and biogas to ensure a reliable and sustainable energy supply. The energy demand in Aras de los Olmos, along with Losilla, has been carefully tracked to improve the quality and reliability of the electricity supply. Data on the municipality's energy consumption has been recorded over several years to identify patterns. On average, the city uses about 150 kWh of electricity per day, with peaks reaching 250 kWh during the busiest times. Weekly data show that most energy is consumed during daylight hours, with a noticeable drop around midday. Monthly consumption varies significantly, peaking in the summer months like August and dropping during the early part of the year, with an average of 120 MWh per month. Annual trends from 2019 to 2022 indicate a steady rise in energy use, with a projected growth rate of 1.4% per year. This gradual increase reflects the shift towards greater electrification and the community's growing reliance on renewable energy sources. The energy system established in Aras de los Olmos integrates multiple renewable energy technologies to create an autonomous and sustainable energy supply for the region. Figure 1 presents the designed system incorporating key components [32]. PV Power Plant (700 kW): A solar power plant equipped with a tracking system is a central component of the renewable energy mix. This PV installation captures and converts solar energy into electricity, contributing significantly to the local energy supply. The tracking system ensures that the solar panels are always positioned optimally to capture maximum sunlight throughout the day. The 700 kW capacity was chosen to account for  
Figure 1: The schematic of the energy system designed for the Aras de Los Olmos area. future growth in energy demand as the minimum required power for the next 30 years, considering a 1.4% annual increase in consumption. Wind Power Plant (200 kW): A wind power facility located in an elevated area captures wind energy and converts it into electricity. This plant diversifies the energy supply and ensures a stable flow of electricity even when other renewable sources may not be as effective. Hydroelectric Power Plant (200 kW): A small-scale hydroelectric plant is integrated into the system, harnessing the power of flowing water to generate electricity. This facility adds a reliable, consistent energy source, especially during lower solar and wind availability. The system includes two water tanks: an upper tank with a capacity of 20,000 m\({}^{3}\) and a lower tank with a capacity of 4000 m\({}^{3}\). These tanks are part of a pumped hydro storage system that stores excess energy. Water can be pumped from the lower to the upper tank when excess renewable energy is available, and it can then be released through turbines to generate electricity when demand is higher or other energy sources are insufficient. A dedicated pumping station manages water movement between the upper and lower tanks. This station ensures the efficient operation of the hydroelectric component of the system, facilitating energy storage and release as needed. Biomass Power Plant (200 kW): The biomass and biogas plant is another vital energy source. Local biomass is processed to produce biogas, which is then used to generate electricity.