Geographical and terrain-specific factors significantly influence the cost of pumped hydro storage (PHS) projects. Here are some key ways these factors impact costs:
Geographical Factors
- Topography and Head: The difference in elevation (head) between the upper and lower reservoirs is crucial. A higher head requires smaller reservoirs and electromechanical equipment, reducing costs for powerhouse construction and tunnel excavation. However, higher heads may also necessitate more complex geotechnical assessments and higher construction costs in certain terrains.
- Geology: The geology of the site affects excavation costs, especially for tunnels and reservoirs. Hard rock formations require more expensive drilling techniques compared to softer soil, increasing overall costs. Geological instability can also impact the structural integrity of dams and tunnels.
- Water Availability: Access to natural water sources can reduce costs by eliminating the need for artificial reservoirs, although closed-loop systems are often preferred to minimize environmental impact. Ensuring minimal operational water losses through seepage or evaporation is important.
Terrain-Specific Factors
- Access and Terrain Complexity: Remote locations with difficult access can increase transportation and construction costs due to logistical challenges. Mountainous terrains may complicate site preparation and equipment transportation.
- Reservoir Size and Shape: Terrain influences the size and shape of reservoirs, which in turn affect costs. Closed-loop systems, often preferred for minimal environmental impact, can be located on suitable terrain, potentially reducing environmental costs but may require larger areas for reservoirs if the terrain is not conducive to high head differences.
Economic Implications
- Construction Costs: Overall construction costs are heavily influenced by site-specific conditions, including geology and topography, which can vary widely between projects. Economies of scale can be achieved with larger projects, but smaller projects might be more costly per unit of capacity due to the lack of scale.
- Component Costs: While higher heads lead to smaller, cheaper electromechanical components, other site factors can increase costs. For example, longer tunnels or complex terrain may offset savings from smaller equipment.
In summary, the cost of pumped hydro storage projects is significantly affected by geographical factors such as topography and geology, and terrain-specific factors like access and reservoir design. These factors influence construction costs, component sizes, and overall project viability.
Original article by NenPower, If reposted, please credit the source: https://nenpower.com/blog/how-do-geographical-and-terrain-specific-factors-affect-the-cost-of-pumped-hydro-storage-projects/
