Play fairway analysis of geothermal resources across the state of Hawaii: 3. Use of development viability criterion to prioritize future exploration targets

A recent Play Fairway Analysis of geothermal prospects in Hawaii identified and compiled data relevant to subsurface heat, fluid, and permeability, and developed and applied a statistical method to integrate the compiled data to produce a map of resource probability across the state. As a final screening of prospective geothermal resources, we considered the viability of development in areas showing an elevated resource probability. This screening was intended to prioritize prospects that have a greater likelihood of proceeding through regulatory review to production in a timely and cost-effective manner. Development viability was determined to be high, medium, or low based on four factors: i) grid accessibility, ii) vulnerability to natural hazards, iii) current and probable future land uses; and iv) community sentiment and acceptance. Development viability was assessed in >10 areas of interest that were selected based on the results of the probability and confidence mapping, and was a guiding criterion used to develop a prioritized roadmap for the next phase of exploration activity in Hawaii. Planned activities include a groundwater sampling and analysis campaign in ∼10 broad areas, and the collection of magnetotelluric and gravity data in 2-5 locations statewide.