Objective
The Department of Defense (DoD) operates significant and strategically important installations in the Arctic and subarctic domain. Geopolitical, economic, and climatic warming effects are requiring DoD to continue Arctic development, requiring the upgrade of existing and installation of new electrical equipment and power distribution systems in these regions. Due to the very low mean annual air temperature in these domains, the soil is typically perennially frozen, and due to the phase change of water to ice, the electrical resistance increases by many orders of magnitude with increasing ground ice content, making earth grounding a great challenge. Various schemes have been developed in the last 50 to 60 years, but these schemes are expensive to install and maintain, and do not meet contemporary standards applied to temperate region grounding systems. Climate warming is compounding the problem, causing a significant increase in lightning strikes in a region which only 30 to 40 years ago experienced few strikes per year: Arctic designers and engineers seldom contemplated the need for lightning protection. Critical infrastructure stakeholders are now specifying installation of lightning protection systems and a verifiable method to ground electrical equipment in permafrost. These are necessary to protect miliary assets and the lives of personnel installing and operating the assets. The overarching objective of this project is to make adjustments to methods, equipment, and protocols to create safe and effective electrical grounding methods for large equipment in frozen earth materials, specifically addressing the challenges posed by permafrost. The project aims to investigate and verify existing grounding schemes while conducting field experiments to establish empirical data and finally creating procedure documents. This research is highly relevant to the DoD as it directly addresses the critical need for reliable electrical grounding practices in cold climates, ensuring the safety and functionality of various DoD operations. The success of this project will be defined by the ability to establish effective grounding methods for large equipment in frozen earth materials, including reducing risks associated with very damaging lightning strikes.
Technology Description
The technology involves a comprehensive study of electrical grounding practices in permafrost that are already in use. This study will begin by conducting a thorough review and analysis of existing grounding schemes used in frozen ground conditions to assess their effectiveness and reliability. The research team will then perform field experiments within the Permafrost Tunnel owned and operated by the Cold Regions Research and Engineering Laboratory in Fairbanks, Alaska. This includes the installation of grounding rods and cable arrays in ice-rich silt, ice-moderate gravels, and ice-poor bedrock, and testing techniques and configurations for earth grounding. The team will precisely measure the electrical resistance (Ohms) of grounded equipment in the test configurations and create practical and actionable recommendations. This information will guide the implementation of reliable grounding practices in cold regions.
Benefits
The study will result in the adoption of reliable electrical grounding methods in frozen ground environments and will enhance safety by minimizing electrical hazard risk to personnel and equipment during DoD operations. The project's outcomes will also contribute to the reliability of electrical systems and equipment, ensuring consistent performance even in extreme cold conditions. Thus, DoD can expect cost savings associated with repair and replacement. Effective electrical grounding is essential for mission success, and transferring the project's outcomes will facilitate uninterrupted operations in these challenging environments. The technological advancements offered by this project will yield significant cost and performance benefits, while ensuring success and safety of military operations in these environments.