- IN WHICH AREAS OF LNG PROJECTS HAVE YOUR CLIENTS EXPERIENCED THE GREATEST EFFICIENCY IMPROVEMENTS?
The selection of the driver for the refrigeration compressors within an LNG plant has a key impact on the overall LNG plant efficiency and capacity. When we look at the efficiency levels related to the rotating equipment, the use of variable speed drive systems (VSDS) in LNG plants, for both the main refrigerant and auxiliaries, allows greater efficiency gains when combined with the use of gas or steam turbines. VSDS are flexible in terms of speed range, with a wide operating range, and can continuously operate at very high efficiency levels. The more traditional solutions for LNG plants use fully mechanical components and our expertise in the power electronics compliments the mechanical equipment and enables the gas or steam turbine to run at better efficiency levels during operation. When we look at the full electrical main refrigerant solution where the power required may be generated in combined cycle, the overall efficiency levels from gas turbine to main compressor can be more than 50% and when we consider the compressor to the VSDS we can see efficiency levels of more than 96%Increasing the overall efficiency allows lower consumption on the electrical grid network. These levels are significantly higher than traditional mechanical efficiency levels of less than <45%, and without counting the losses related to the planned maintenance (mechanical rotating parts).
Another advantage of using VSDS lies in the latest active front end topology (AFE) which allows more stable grid management and smoother operations. The technology allows the excess of energy to be recirculated to help ensure the gas turbine can continuously operate at the highest efficiency point. The unique power factor on the grid provided by the AFE can allow optimization of the design and size of the power generation unit, which can result in lower footprint and cost optimization for the end user. Plant simplification and less environmental impact can also be achieved in the use of electrical drivers.
- WHAT CAN BE THE BIGGEST CHALLENGE IN ENERGY CONNECTIONS FOR LNG AND HOW DO YOU OVERCOME IT?
Highly reliable product selection can be considered mandatory in LNG Projects, however not enough emphasis is placed on this when the whole plant is not approached as a unique system. The key to success for these LNG plants is the full integration of the different components and the capability to predict how each of them is going to interact mutually. Over the years, GE Oil & Gas has developed and tuned its codes to help predict the dynamic behavior of these trains both on the gas side and with the mechanical interaction. This is particularly important for electric motor-driven compressors (either used as main drivers or as helper/starters) for the well-known inter-harmonic effects generated by the motor and the possible mechanical excitations resulting on the train (sub-synchronous interaction [SSI], sub-synchronous torsional interaction [SSTI]).
Deep knowledge of the whole system (both mechanical and electrical) is key as it allows the best maintenance and failure predictability…ensuring continuous operation. The best way to manage the plant is to have no impact from the electrical device to ensure no stoppages in the production.
- WHAT CAN BE SOME OF THE BIGGEST PAIN POINTS FOR LNG PROJECTS?
- Gas prices…electricity prices...losses in production...carbon tax and environment impact can all impact on LNG projects. Different operators may have different criticalities related to individual plants and there may be lots of different restrictions in place for each of the plants. This complexity and individuality needs to be addressed and understood to ensure the optimal configurations to meet these requirements.
- Reliable and efficient technology is key to achieving longer term savings and adding value to oil & gas operations. Thats why we believe that GE’s high power induction motor and VSI drive technology has a big role to play in the future for the LNG industry. This technology achieves the best of both worlds, lowering costs while increasing performance, whether that is through optimisation of the entire train, the ability to extend maintenance intervals, or in the simplicity of design to allow more reliable operations.
- Managing technical risk and ensuring a proper balance between different technical solutions for LNG operations can be tough and a big pain point for LNG projects – and by not mitigating these risks, there can be a big impact in terms of project timings and costs.
Addressing all these pain points is where GE’s expertise and detailed knowledge of LNG operations enables us to offer the right solution. We have expertise in LNG…we can tailor our solutions by partnering with our customers early in the project (FEED/Pre FEED) and at the very beginning of the process, evaluating the complete system and completing the network analysis to help deliver better solutions.
- WHICH PROJECT/S ARE YOU MOST PROUD OF AND WHY?
GE has a long history of helping LNG customers overcome some of the challenges that the industry can present…through creating technologies that help to reduce carbon emissions, help lower overall project costs and help increase the speed of transport of LNG as global demand increases. When we look at some of the projects that I am particularly proud of, I would highlight two big achievements for GE in driving LNG forward:
- World’s largest eLNG - The Freeport eLNG project is unique in electric power systems design and implementation. The plant will feature all-electric drive compression directly connected at the utility incoming transmission voltage level, and when in operation, is expected to be the largest electrical driven LNG plant in the world. The power systems engineering study and design for Freeport uses the deep power systems expertise of GE’s consulting team, and as a result GE will supply the main refrigeration compressor trains driven by large VSDS LCI drive with high power synchronous motors.
- GE Massa Test Bench - GE is continually investing in the already world-class capabilities of its testing facility in Massa, Italy. The 61MW test bed is designed for thermodynamic and mechanical running tests on large centrifugal compressors for LNG and ethylene applications. This was utilised to test the equipment being delivered to one of the world’s LNG mega projects and enabled GE to successfully test and validate the mechanical components at full load, and helped our customer avoid the typically more expensive and longer cycle string test configurations used elsewhere. It’s also a great reference for us in validating our VSI drive technology.
- WHAT ARE SOME OF THE CHALLENGES YOU FACE IN THE LNG PROJECTS?
LNG projects can face a number of challenges due to the complexity of the technology involved, high infrastructure costs and the strict regulatory frameworks around the environmental impact of extraction and processing. Over the last fifteen years, GE has helped the industry overcome these challenges. As demand for LNG continues to increase, technological innovations are crucial to maintain the competitiveness of the industry and to maximise performance. GE is continuing to invest in the testing and development of new technologies to advance the efficiency of LNG systems for years to come.