A Methodology for Geothermal Pipeline Route Selection Based on Genetic Algorithms and Distance Transforms

Abstract

The objective of this study is to develop a methodology and to create a tool for use in geothermal pipeline route selection. Special emphasis is placed on the method finding the shortest route and minimizing the visual affects of the pipeline. Among other constraints that can be incorporated into the method are: Type of flow regime, pressure drop, building costs, inaccessible areas and maximum allowable gradients. Included in the tool is site selection for separators and pipeline gathering points based on visual effects, land costs, inaccessible areas and total distance to boreholes.

The method uses a combination of variable topography distance transform algorithms and a new extension to multiple weight distance transform algorithms. A method is presented to rank each point in a grid (representing some topography) based on visibility with regards to roads, buildings and public areas. The method works with a digital representation of the geothermal area in question called Digital Elevation Models (DEM) which is a digital file consisting of terrain elevations for ground positions at regularly spaced horizontal intervals. The method is implemented for pipeline route selection in the Hverahlíð geothermal area. The visual effects of the route recommended by the method are compared to those of the shortest possible route and the route proposed in the original planning for the geothermal area.