Seasonal and Temperature Variation of soil

Technical Report from the year 2011 in the subject Engineering - Power Engineering, grade: A, Atlantic International University (Niger Delta University), course: STV 678, language: English, abstract: The strategic position of Port Harcourt in the Niger Delta region has made the city one of the fastest growing cities in Nigeria. The Niger Delta which is rich in oil and gas provide Nigeria with Ninety-five percent foreign earnings. The oil companies operating in the state has attracted several small, medium and large scale industries. The telecommunication industry which is the fastest growing company in Nigeria has provided job opportunities through several mini companies. Whether small, medium or large companies require the use of electricity and electrical equipments and therefore require proper and safe earthing (grounding). The electrical, electronics and the telecommunication industries require various grounding methods, therefore it is necessary to study the seasonal variation and temperature effect on the grounding systems.
All calculations related to the design of grounding system and the determination of transfer, step and touch potential require information about the soil resistivity at site. Resistivity of soil depends on the physical composition of the soil, moisture content, dissolved salts, season variation, current magnitude and soil temperature. Different soil compositions have different average resistivity but moisture has great influence on the resistivity value of soil. For example, the resistivity of clay varies from 4ohm-m to 150 ohm-m depending on the water content. The study therefore will enable earth system designers, installation engineers to have available records of the earth parameters in this growing city that will enable designers and installer to install safe and reliable system.