The electrical submersible pump (ESP) is an essential and critical component in most low-enthalpy geothermal wells where high volumes of hot (up to 120°C) and harsh geothermal brine is required to be transported to the surface. Despite a great deal of knowledge and experience in the design and operation of ESP in the petroleum and water sector, reliability of geothermal ESPs requires further improvement. Frequent failures have been observed that resulted from sub-optimum design, installation and operation of these systems which made the lifetime of them shorter than the expected 5-7 years. In this paper we summarize the typical conditions in low-enthalpy geothermal systems (specifically in the Netherlands) and several observed reliability challenges. Lastly, we will discuss the gaps between the petroleum, water and geothermal practices and identify a list of R&D opportunities to better understand the geothermal ESP failures and improve ESP reliability. Testing ESPs in realistic geothermal conditions and a proper monitoring of the well-ESP system is crucial to improve the reliability of existing ESP designs and can enable the development of new geothermal ESP system designs.