Designing a robust and reliable underground electrical distribution system is a complex process that requires careful planning to ensure long-term performance and safety. The key considerations include:

• Cable Selection and Ampacity: The type of cable (e.g., XLPE) and its size must be carefully chosen to handle the required current-carrying capacity (ampacity) without overheating. Since underground cables dissipate heat less effectively than overhead lines, this is a critical design factor.

• Conduit and Duct System: The choice between direct burial and a conduit-based system impacts both initial cost and future maintenance. A conduit system allows for easier replacement and expansion but adds to the upfront cost. Conduit fill ratios must be strictly followed to prevent jamming and facilitate smooth cable pulling.

• Routing and Environmental Factors: The cable route must avoid other buried utilities (gas, water, telecom) and account for soil conditions, moisture levels, and the presence of any heat sources. Proper burial depth is also critical to protect the cable from accidental damage from digging or heavy surface loads.

• Access and Maintenance: The design must include strategically placed manholes, vaults, and junction boxes at regular intervals and at all major bends. These access points are essential for both the initial installation (allowing for pulling points) and for future maintenance and fault location.