| Abstract |
The presentation will discuss the application, benefits and challenges of using high voltage Electrical Submersible Pumps (ESPs) in geothermal wells. Despite the benefits of high voltage ESPs, Line Shaft Pumps have been the primary lift method of choice in Iceland up to this point. By using high voltage ESPs, the developer can achieve greater depths, increased efficiency, lower cost, higher operating temperatures, lower noise, faster installation (less downtime) and the 24/7 monitoring of downhole conditions. ESPs have a very large appetite for power, but also have the highest output of fluid versus all other lift types. Retrievable ESP packer technology also allows controlled production from various depths of the well. Veitur Utilities is the largest utility company in Iceland. Veitur main responsibilities are distribution of hot water, electricity, potable water and sewage system throughout the Capital region as well as several municipalities both in the south and west of Iceland. Their distribution system is extensive; pipes and cables total 9,000 km in length, corresponding to the distance from ReykjavÃk to Shanghai. Veitur operate more than 80 geothermal wells producing up to 3200 l/s of geothermal fluid and 2300 l/s of heated ground water for district heating systems of more than 1,34 GWth for 13 individual district heating systems providing heat for more than 230.000 people. A majority of Veitur’s wells are using Line Shaft Pump as the lift selection. However, beginning in 2018, Veitur started implementing Schlumberger ESP systems as a solution in Iceland. The first installation took place in Laugaland in S-Iceland in December 2018 following a detailed design, manufacturing and delivery process. A second installation took place at Bakki, S-Iceland early 2019. The presentation will reveal multiple case studies with specific details surrounding technical design philosophy, depth, temperature, flowrate, installation date, accumulated production and ESP uptime. These case studies will highlight specific success stories, challenges and lessons learned during the planning and installation phases. |