WorldWide Drilling Resource

41 WorldWide Drilling Resource ® JUNE 2013 Newberry EGS Project Prepares to Drill Adapted from information by AltaRock Energy AltaRock Energy announced it suc- cessfully createdmultiple stimulated zones from a single wellbore at the Newberry enhanced geothermal system (EGS) de- monstration site in Oregon. Creating multiple stimulated zones from a single well will dramatically in- crease the flow and energy output per well for the completed system, which will include soon-to-be-drilled production wells. The overall result will lower the cost of geo- thermal energy production by as much as 50%. "Geothermal energy has the smallest environmental footprint of any renewable power source we now have, and is the only renewable energy source that pro- vides 24/7 baseload power," said Susan Petty, president and founder of AltaRock Energy. "The purpose of the Newberry EGS project is to demonstrate AltaRock's new technology designed to lower the cost of EGS, and thus allow economic extraction of heat from the earth in loca- tions where high temperatures can be reached by conventional drilling tech- niques." Injecting cold water at a moderate pressure increases the porosity of hot, low-permeability rocks enhancing the reservoir’s existing fractures. This means EGS could theoretically be sited any- where geothermal heat is close enough to the surface to be recovered economi- cally. Studies by the Department of Energy, the U.S. Geological Survey, and Google ® have concluded EGS technology could unleash at least 500 gigawatts (GW) of recoverable geothermal energy in the Western U.S. alone and potentially over 3000 GW across the country. Until now, a major challenge facing EGS projects has been the cost. Since geothermal wells can cost several million dollars to drill, increasing the generation capacity of each well is important for mak- ing it more competitive on the open mar- ket for electricity because it lowers the Photo courtesy of Business Wire. cost of the produced power by reducing the number of wells that need to be drilled. Systems with single stimulated zones simply don't yield enough power per well to make the electricity produced cost effective. Having the ability to create mul- tiple stimulated zones from a single well increases the amount of power produced by the well, and decreases the overall cost of the power produced. In the spring of 2013, AltaRock will test for permeability, flow rates, and heat- capturing properties of the reservoirs cre- ated. After that, production wells will be drilled to intersect the reservoirs about 1500 feet away from the injection well. Once a connection between wells is made, the well system - one injector and at least one producer - will be flow tested to determine if the system can support a commercial plant. If a commercial plant is feasible, a design will be developed, and construction permits will be submit- ted to regulators. It is a long process, but the potential payoff in renewable domes- tic energy is enormous.