Innovative CO2 Reduction Methods for Drilling and Workover Operations

In view of global climate targets, the oil and gas industry faces the challenge of significantly reducing CO2 emissions, particularly in energy intensive processes, such as the operations performed by a German Well Service Company, for the workover of existing oilfields in Germany and Austria, especially heavy workover. These rigs consume a considerable quantity of fossil fuel every year which further leads to high CO2 emissions.
This thesis faces the problem of the high amount of emitted CO2 and analyses different methods which show, if there is a way to save emissions and applicability. The use of hydrogen (H2) as an alternative energy source, which is offering promising opportunities (on the one hand to reduce the amount of used fossil fuels and on the other hand to receive a cleaner combustion) to reduce the CO2 emissions and minimize the ecological footprint.

Another point for achieving this goal is to increase the efficiency and therefore optimize the engine performance. This is achieved by operating the motor at its best efficiency point (BEP), reducing specific energy consumption and CO2 emissions Any surplus in energy generated (in the difference of needed energy to the energy produced at BEP) can be stored in a battery, supercapacitors, kinetic or potential energy storages such as flywheels or gravitational storage options or used alternatively.
In addition to these techniques, the integration of photovoltaic (PV) systems is being analysed to cover all the energy requirements of the heavy workover systems with renewable energy sources. PV systems can be used for both direct power supply and for charging energy storage systems, further reducing the consumption of fossil fuels.
This thesis shows that the use of H2 injection, energy storage and integration of photovoltaic systems is a promising strategy for a significant reduction in CO₂ emissions resulting from heavy workover rigs. At the same time, the energy efficiency of the plants is increased, which gives an important contribution to the decarbonization of workover operations in the oil and gas industry.