Q&A: Providing artificial lift systems for geothermal applications
Andy Limanowka, engineering and product development at Oil Dynamics GmbH, answers questions about this segment of the market
What is the role of geothermal energy within the wider energy production segment?
The role of geothermal is to supplement the global supply of energy. It will not replace natural gas or oil anytime soon. But compared to solar and wind power, it is the only “green energy” available on demand.
In which regions will it mostly be possible?
In countries which on one hand subsidize geothermal energy and on the other hand have accessible geothermal reservoirs. It is however still a long way to go to develop sustainable systems with acceptable run life compared to conventional energy producers.
How does the potential of geothermal energy differ from region to region?
The potential mostly differs based on available temperatures. For example in the area south of Munich a typical producer would be 150l/s, BHT 140C, pump BHP around 1800HP and the application would be power generation, in the Netherlands a typical producer would register 70l/s, BHT 90C, pump BHP around 800HP and the application would be residential or agricultural heating.
Where do you see most potential at present and why?
I would say in Europe in general and Germany or the Netherlands specifically. Europe is pioneering renewable energies and we are a German company. The Netherlands are making big strives moving away from gas towards renewables like geothermal; further the applications are easier than the German ones.
What might geothermal energy generally contribute to the current energy revolution?
At this moment not a large percentage however; further technical development will broaden the scope of applications. The availability of geothermal heat is virtually unlimited and it definitely can be advertised as a “green energy”.
How much is geothermal energy being used in different countries like Greece, Germany or the Netherlands?
As mentioned before, the technology is still in a state of development and we need to differentiate between free flowing wells and wells that need artificial lift technology (which definitely is our preference). Countries like Turkey, Iceland and Indonesia for example have significant potential through free flowing wells; central European countries on the other hand need the assistance of artificial lift technologies to harvest the energy.
Under practical aspects: What are the limits of this technology?
In general, higher water temperature delivers more energy, higher volume will bring more energy but that is just choice, not requirement. The current OD limitation is 150l/s, BHT 150C, max. pump BHP is about 2000 HP. Products available from other suppliers are limited by BHT 250C but as far as I know only for low volumes and low HP (500HP). Like everywhere, the development goes towards larger plant capacities.
Which particular requirements are in need for geothermal supply on electricity and heat? How do they differ?
For power generation that would be high volume and high BHT, for a residential heating a low volume and BHT below 90C.
Which challenges are you having with engineering products for clients in the geothermal industry?
The challenges are manifold and range from construction materials over thermal expansion challenges to electrical insulation problems. It is definitely is a wide playing ground for engineers and will remain to be interesting.
And how do you deal with it once a project is getting started?
Every project we do receives special attention in our organization. At the outset a project team is formed and a project manager will be appointed. This assures us that all aspects of the project, technical, application, commercial, field service and logistics will be considered and applied. Being a small company gives us the possibility to act flexible and fast and to make individual decisions as they are required. This also applies for engineering.
What’s the feedback you have been getting so far from any geothermal project partners?
The feedback received has been very positive so far. Our clients like to receive this special attention. They also appreciate our willingness to work with them towards product and operational improvements based on actual operating feedback. Our shared goal is to continuously improve the Mean Time Between Failures (MTBF) for artificial lift systems in geothermal applications.