Why Not Geothermal Energy as Base Load Power?

This Colorado Energy News article ponders the question of using geothermal energy as base load power. Base load is the power necessary to provide electricity 24 hours per day. As much as we would like them to, the sun doesn't shine 24 hours per day and the wind doesn't blow consistently. So we need a reliable power source (currently burning coal) that will provide a constant flow of electricity. According to the article, the United States has an abundance of geothermal resources underneath. So why not geothermal? Read the article and find out!