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Sultan Al-Shneiber is a Reliability Engineer with Saudi Aramco, Abqaiq Plants. He is driven by the knowledge of Mechatronics Engineering from California State University Chico. He supports operation and maintenance in different tasks such as trip investigations, overhauling equipment, troubleshooting, evaluate new technologies, MTBF analysis, assessments and studies on rotating equipment. Rami Al-Shneiber is a Reliability Engineer at Saudi Aramco. For more information, visit Aramco.com

Assessing asset life cycle, condition, reliability, and performance

Turbomachinery International spoke with James Montgomery, Chief Design Engineer, Novel Nuclear, and John Mason, Systems Design and Integration Technical Specialist of Rolls-Royce, to take a deep dive into micro-reactors—compact, portable reactors that produce thermal energy for use as heat or electrical power—and give readers an inside look at the company’s innovations, challenges, and design considerations for its micro-reactor and nuclear technology in terrestrial and lunar applications.

Q: What is a micro-reactor, and how does it differ from a small modular reactor (SMR)?

Micro-reactors are very small scale, in the range of 1 MWe - 10 MWe compared to a typical grid-supplying power plant in the gigawatt range and compared to the new generation of SMRs in the 1/2 GW range—micro-reactors are much smaller than that. We have two potential applications for the micro-technology we’re working on in the United Kingdom: The first one is the terrestrial variant for supplying power to different applications on Earth; and the second is the space micro-reactor that has potential applications for the lunar base as part of the space program and, in the longer term, for power and propulsion applications on satellite and deep-space missions.

Q: What goes into designing a micro-reactor, and how are they customized?

At Rolls-Royce, we have a great pedigree in designing complex systems like this, so the first step in that process is to work with potential end users to understand the user requirements and use cases where we can get value from the technology. Then we’ll work through the process of preliminary design and size of the plant, understanding what the technology can do and where the technology gaps might be. That launches us into a technology program to acquire the technologies we need.

The micro-reactor plant is interesting because it’s genuinely a new product for us at Rolls-Royce, as with the rest of the industry. We’ve pieced together some of our pedigree from the nuclear side and the turbomachinery side that we have developed over many years for aerospace and industrial applications.

Across the Rolls-Royce group, we have experience in several different industries and capabilities. We have large civil engines that power airliners. We are engaged in combat aircraft and military transports, and a large element of our business looks at turbomachinery for turbo-compressors— centrifugal machines, turbochargers for yachts, large mining and industrial applications, etc. We can pull from all these capabilities and experiences and apply them to new industries and new technologies.

Q: What advantages do micro-reactors offer, and in what environments/locations do they work best?

In terms of the terrestrial variant of the micro-reactor, imagine a small-scale power plant in a shipping container-sized envelope that can be deployed to a remote location where access to fossil fuels is strained—that’s our vision for the micro-reactor. The great thing about a micro-reactor is, depending on its size and detailed design, it can be fueled for five to 10 years of operation, which means if you are a remote-unit or -running community or a remote military installation, it makes you resilient to the risks surrounding the fossil-fuel supply chain. Also, as a net-zero technology, it eliminates reliance on fossil fuels for communities.

The space micro-reactor is a completely different application. Many different missions are looking to use these kinds of power plants: In particular, NASA’s Fission Surface Power Project, as part of the Artemis Mission, was looking to develop a power plant for use on the lunar base. There, it’s about operating in areas where solar power is limited, particularly around the south part of the moon where we’re looking to explore, so having a nuclear source that can run reliably day and night is a game changer for moon-based operations.

In the long term, nuclear can be used as a source of power for propulsion and space missions, particularly for deeper space missions where solar power become weaker.

The Artemis Mission aims to build an infrastructure to Mars, and this technology could extend to those kinds of missions' demands. 

From a power-conversion viewpoint on our terrestrial applications, we can utilize our knowledge and expertise gained from our naval applications. These are designed and packaged to fit in a confined space envelope, similar to an ISO container, which is needed to transport the system. With an open Brayton Cycle, we are simply replacing the combustion chamber, where normally fuel is burned, with a heat exchanger to the reactor.

Where things get very interesting from a power-conversion point of view is with space applications. We still use Brayton cycles, but operation in space requires a closed cycle—we can’t continue to take air in the front and push it out the back, so we take the exhaust gas out of the back of the turbine and recondition that flow back to where we started before it re-enters the compressor. So, we’re looking at the most efficient way to do that with recuperation intercooling and various other things.

This presents challenges, but it also gives us additional design levers—because it’s a closed cycle, we can change the working fluid, so, for example, we don’t have to use air as we do with the open cycles for civil aircraft. We can also change the start conditions—optimize it by changing the pressures and temperatures at the beginning of the cycle. Depending on the requirements of the system, we can pick and choose where the design point of the turbomachinery sits.

Q: Can you talk about the use of nuclear energy and its role in a sustainable future?

One of the key technologies that enable micro-reactors is the development of coated-particle nuclear fuel, TRistructural ISOtropic (TRISO) fuel: a kernel of uranium fuel coated in different layers of carbon-like material that has different functionalities for protecting the fuel from overheating and for containing fission products within that small particle in a resilient way. This means that we can potentially simplify the design of the rest of the plant and hence enable much smaller plants more than we’ve historically been able to achieve safely. There are other aspects of the plant as well that are being looked at within the industry to enable a passively safe nuclear design—by that we mean it’s effectively fail-safe from the way it responds to different failure modes.

In terms of power conversion, the key impact of the micro-reactor and heat transfer from the reactor into our cycle is the peak temperature that goes with the fuels and technologies of that reactor. They are much lower than the operating temperatures of civil airliners, and the technology in the power conversion and Brayton Cycle is not being pushed by the cycle’s temperature levels. It gives us other headaches in terms of trying to design the cycle for high efficiency to minimize the size of the overall system, the reactor core, and the amount of fuel needed for the lifetime of the application.

One of the interesting applications for terrestrial micro-reactors is the need to safely transport and operate it at a remote site. As part of our concept, we'll have a containerized solution and ship it to the site using conventional transport. That itself poses design challenges to the way that you transport the radioactive and spent fuel when the site has been decommissioned. There's a lot of work in the industry looking at that.

It gives a flexible solution to the customer because you could have multiple nuclear reactor modules to create nuclear heat combined with multiple modules of John's power-conversion technology to scale the plant to different applications, which could also include the supply of heat for chemical and industrial processes.

The primary fluid used in the Brayton Cycle provides the coolant for the reactor as well. So, there are a lot of scenarios that we don't normally face when designing the system that we need to incorporate additional functionalities for and make sure there's the right redundancy to provide the safety case for these reactors. There are cases that in a normal application—for example, a civil airliner in which you would reduce the power or shut the engine down and rely on other engines to complete the flight safely—that may not work for the nuclear side because it needs to flow continuously to cool the reactor, which will have a big impact on how the system is designed.

Another factor is the environment in which these systems will operate. There are opportunities to use these in various conditions, from cold, Arctic conditions to hot, desert-like conditions such as in mining communities, and these intake conditions for terrestrial systems have a very big impact on their performance. We have to account for these factors when designing what the system and turbomachinery look like to ensure good performance and efficiency throughout each case.

Ambient temperature is a huge factor for space conditions in lunar applications—the day-to-night temperature varies between 100° Kelvin - 385° Kelvin, that’s -300° F - +230° F. That will have a huge impact on our ability to reject heat from the system through the radiators to return the fluid to its starting condition before it goes back through the compressor. From a systems-level point of view, there are many things that we need to think about which do we design for? Peak efficiency of power conversion, which minimizes the size of the reactor plant needed to launch and the amount of fuel you need to take with you? Or do we design for the minimum size of radiators that have to be packaged into the rocket to get the reactors there in the first place? There are many things we have to think about that we don’t normally consider.

This is a really interesting product for us because it brings together our aerospace heritage and our knowledge of how to build lightweight aerospace systems with our nuclear heritage. But this is our first nuclear application where weight has been a real concern, both from a transport point of view for the terrestrial reactor and for the spacecraft where the payload mass and volume are key constraints on the system. So, that's giving us a real challenge and driving us to some interesting packaging solutions for the space reactor in particular.

TurboTime Podcast: Micro-Reactors with Rolls-Royce.

Rolls-Royce is using its nuclear and turbomachinery heritage to create micro-reactors for space and terrestrial applications.

Q&A: Micro-Reactors with Rolls-Royce

In this episode of the TurboTime podcast, James Montgomery and John Mason of Rolls-Royce talk about micro-reactors. Microreactors are compact, portable reactors that produce thermal energy, which can be used as heat or converted to electric power. Micro-reactors can be quickly deployed and installed, and when they utilize a responsive design concept, they can prevent overheating and require fewer components, fewer operators, and less maintenance.

Montgomery is the Chief Design Engineer for the Rolls-Royce novel nuclear team in the United Kingdom. He is responsible for the design of the overall micro-reactor plant. Mason is a Systems Design and Integration Technical Specialist working within the Novel Concepts team in Bristol within Future Programs. His responsibilities are around the power-conversion system that goes with micro-reactors—i.e., the turbomachinery that takes heat from the reactor and converts it into usable electrical power.

“Micro-reactors are very small scale, in the range of 1 MW - 10 MW electrical, and that’s compared to a typical grid-supplying power plant that's in the gigawatt range and also with the new generation of small modular reactors that are in the 1/2 GW range, so we're much smaller than that,” Montgomery explained. “We have two potential applications for the microtechnology we're working on in the United Kingdom: The first one is the terrestrial variant for supplying power to different applications on Earth; and the second is the space micro-reactor that has potential applications for the lunar base as part of the space program and, in the longer term, for power and propulsion applications on satellite and deep-space missions.”

Montgomery also explained the process of designing a micro-reactor: “At Rolls Royce, we have a great pedigree in designing complex systems like this, so the first step in that process is to work with potential end users to understand the user requirements and use cases where we can get value from the technology. Then we'll work through the process of preliminary design and size of the plant, understanding what the technology can do and where the technology gaps might be. That then launches us into a technology program to acquire the technologies we need.

“The microreactor plant is really interesting from that point of view because it's genuinely a new product for us at Rolls-Royce as with the rest of the industry,” Montgomery continued. “So, we've pieced together some of our pedigree from the nuclear side and the turbomachinery side that we have developed over many years for aerospace and industrial applications.”

In this episode of the TurboTime podcast, James Montgomery and John Mason of Rolls-Royce talk about micro-reactors. 

TurboTime Podcast: Micro-Reactors with Rolls-Royce

Rolls-Royce SMR announced signing a supply partnership agreement with Siemens Energy

. Under the agreement, Siemens Energy will supply steam turbines, generators, and other auxiliary systems for Rolls-Royce SMR's planned Generation 3+ modular nuclear power plants.

Karim Amin, a Siemens Energy Executive Board member, said we are experiencing a global nuclear energy renaissance. “Numerous countries are turning to nuclear technology to produce low-emission electricity, and small modular reactors (SMRs) will play a key role in this. Siemens Energy brings decades of experience in conventional equipment, while Rolls-Royce has the necessary implementation expertise. This perfect symbiosis enables us to shape the future of energy supply jointly. We are pleased to work with Rolls-Royce SMR on this exciting project."

 followed up with Felix Aschendorf, Sales Director Nuclear at Siemens Energy, to discuss its role as Rolls-Royce’s “global turbine systems partner” for conventional technology for SMRs, technical challenges, and nuclear trends.

TURBO: What are the unique challenges and solutions involved in ensuring seamless compatibility and optimized performance within a standardized, modular framework compared to traditional large-scale nuclear plant integrations?

 Siemens Energy is focusing on built certainty and performance and cost optimization. As a result, we have also developed a module system for our combined-cycle power plant business. This modular approach has already been executed and operated onsite by our Gas Services team. We believe this approach will bring down construction times and costs. A challenge is to ensure a modularized approach where it provides a benefit on the one hand and a smooth operation and maintainability for the entire lifetime of the nuclear power station on the other hand.

TURBO: Are there technical challenges and/or advantages associated with designing and manufacturing standardized steam turbines and generators for a fleet of SMRs at a modular nuclear power plant?

 Siemens Energy's steam turbine and generator sets are based on a modular approach and can, therefore, be easily adapted to project-specific needs. Siemens Energy's key strategy is to develop steam turbine frame families to cover a broad range of power output, use cases, and variation of project-specific requirements while focusing on a maximum degree of standardization.

TURBO: What trends is Siemens Energy seeing in nuclear, SMRs, and modular power plant designs?

 There is one common top priority among all nuclear developers, whether micro-modular nuclear, SMR, or large-scale nuclear: bringing down construction time and costs. Standardization and modularization are key levers in the nuclear industry that support this goal. In addition, there are also various GEN IV SMR developments ongoing, focusing on different technologies, such as lead-cooled, molten-salt, or pebble-bed reactor types. Such future reactor technologies will enable the industry to reduce dependence on Uranium-235 and improve the situation regarding nuclear waste. GEN IV developments target new use cases by offering a small footprint and relatively small power output for floating applications or remote areas without a grid connection.

Felix Aschendorf from Siemens Energy says there is one top priority among nuclear developers: reducing construction time and costs.

Siemens Energy Talks Modular Technologies, Nuclear Trends

Welcome to the fifth edition of the Turbomachinery News Network. I’m James Cook, assistant editor at 

The Turbomachinery News Network, for the week of April 14, 2025, covers news from EnBW, the Port of Rotterdam, Venture Global, MAN Energy Solutions, and GE Vernova.

EnBW Commissions Plant, Rotterdam Conducts Pilot, Calcasieu Pass Enters Operation, MAN Supplies Propulsion, GE Vernova Equips Plant

EnBW commissioned a power plant equipped with hydrogen-ready gas turbines, one of Germany’s first, at the 

 waste incineration site. EnBW modernized the site with a 62-MW turbine construction featuring waste-heat boilers and hot-water boilers. The new plant will generate 124 MW of electrical energy and 370 MW of thermal energy for Stuttgart.

 between two vessels that transferred 800 cubic meters of liquefied ammonia at -33 ºC. It took approximately 2.5 hours alongside a newly constructed concrete quay. The demonstration validated the Port of Rotterdam Authority’s safety system for ammonia bunkering, with the first ammonia-bunker-fueled ships arriving in 2026 - 2027.

 export facility into commercial operation, allowing long-term customers to offtake low-cost LNG just 68 months after reaching final investment decision. The facility, among the fastest greenfield LNG projects completed to date, holds numerous multi-billion-dollar contracts with key European trade allies. These customers will receive North American LNG for 20-year terms.

In the maritime sector,MAN Energy Solutions will deliver 10 

 to Hindustan Shipyard in India, which will build five fleet support ships for the Indian Navy.

 in Japan kicked off operation using three GE Vernova 9HA.02 gas turbines, three heat recovery steam generators, and steam turbines and generators from Toshiba. The HRSGs were manufactured as pressure part modules in GE Vernova’s factory in South Korea and assembled into prefabricated supermodules in Tongyeong before maritime shipment to Japan. The Goi Thermal Power Station may reduce CO

 emissions by 16% compared to the original plant.

Since 1983, energy executives have made the trek to Houston for CERAWeek, often referred to as the Superbowl for the energy industry. What started out as an oil and gas conference for a few dozen now draws more than 10,000 attendees with 1,400 speakers from 89 countries. And “energy” includes oil and gas, coal and nuclear, renewable energy sources (solar, wind, geothermal, hydro), and energy storage.

First to the stage: U.S. Department of Energy (DOE) Secretary Chris Wright

The message was clear: There’s a new sheriff in town with new priorities for U.S. energy policy. At CERAWeek 2024, then-U.S. DOE Secretary Jennifer Granholm told the audience, “LNG exports will soon be in the rear-view mirror.” Today’s U.S. DOE Secretary, Chris Wright, works in an alternate universe seeking energy supply dominance. Wright removed the “pause” invoked on permitting LNG projects by Granholm and is providing permitting support to speed up the construction of pipelines and LNG export facilities.

“Climate change is a global physical phenomenon that is a side effect of building the modern world. I am a climate realist. Everything in life involves trade-offs. Everything,” Wright said.

At CERAWeek 2024, the conference was abuzz with the realization that AI has created demand for more electricity than had been forecasted. However, since March 2024, the magnitude of the pending electricity shortage has become more fully understood. AI has evolved from a gradual step-up in productivity to an Arms race.

“The implications on national defense make it simply critical that America leads the AI race,” Wright said.

Stated more directly at CERAWeek by Doug Bergum, U.S. Secretary of the Interior, having global atmospheric temperatures increase by 2 degrees by 2050 is not an existential threat.

“The two existential threats at hand are Iran getting nuclear weapons and losing the AI war,” he said.

More generation capacity of all types is needed immediately to supply the electricity-hungry AI data centers. Utilities and developers in many regions of the United States are racing to install baseload gas turbine combined-cycle power, but they can’t get it fast enough 

. Deliveries for large gas turbines from GE Vernova, Siemens Energy, and Mitsubishi are now being scheduled for 2028 - 2029. Once the turbines are delivered to the site, it typically takes approximately 12 months to build out a combined-cycle plant. Heat recovery steam generators (HRSG), step-up (or step-down) transformers, and other electrical equipment have their own supply-chain challenges.

John Ketchum, CEO of NextEra Corp., the largest utility company in the United States, lamented, “We completed a modern combined cycle in 2022 for $785 per KW, but a new build for 2030 commercial operation will cost $2,400 per KW.”

There will be winners and losers in the race for AI dominance and quantum computing market share. Amazon, Microsoft, Alphabet (Google), META (Facebook), and Oracle are all investing billions and racing aggressively to get a competitive edge.

With the large gas turbine supply essentially sold out for the next three to four years, other solutions are coming into play:

Buying or leasing smaller gas turbines or reciprocating engine gensets as a short-term bridge

Unretiring mothballed nuclear plants and coal plants

Upgrading transmission lines to de-bottleneck the grid

Using demand-side management to create “virtual power plants” to reduce peak load.

The power surge from AI will need all these solutions and more.

Energy Transition Reinvented—Now Energy Addition

The power surge from AI has done more than create a bonanza for turbine OEMs and engineering, procurement, and construction contractors. “Build Baby Build” has also brought about the remake of the energy transition to the energy addition.The energy trilemma of security, affordability, and sustainability has been reshaped 

.Security and affordability now rule the roost as practical solutions rise to the top. Funding for the green energy fantasy of green hydrogen (or any hydrogen) is fading rapidly. Offshore wind generation is not financeable in most regions of the world without substantial government subsidy. Carbon capture as a universal attachment to all gas and coal plants is not affordable. Specialized carbon-capture projects at huge sequestration hubs with substantial economies of scale may survive. Ironically, OXY’s direct air capture technology shows some promise by removing CO

 from the atmosphere and injecting the CO

directly into oil and gas formations to enhance production of more oil and gas, thus linking to the energy addition.

Modular nuclear reactors are getting serious attention for providing carbon-free baseload generation. A nuclear renaissance has been talked about for decades but could never overcome the history of project costs far exceeding budgets. Now, a new approach is on the table: SMRs built offsite in a factory and delivered to the job site, perhaps adjacent to an existing nuke or fossil-fueled plant.

There is also a race to establish the SMR design that could become the standard for the new era of nukes. GE Vernova, with Hitachi, is promoting a 300-MW SMR and plans to begin operation of unit 1 of 4 in 2029 at an existing nuclear power plant at Darlington (Toronto), Ontario. Other SMR designs by NuScale Corp., Google, and Amazon are focused on design modules in the 80 – 100 MW size, modeled after the U.S. Savannah commercial cargo ship 

On the last day of CERAWeek, Alaska Governor Mike Dunleavy described, with great enthusiasm, his outlook for a $44 Billion LNG export project. The Alaska LNG Project has three major components:

A 3.5 BCFD gas-gathering and processing plant on the north slope, an 800-mile 42-inch pipeline to Niniski (near Anchorage), and a 20 million MTPA liquefaction near Kenai. The project also includes carbon capture.

Construction of the gas pipeline would begin in 2026 with gas flowing in 2028.

The conditioning plant and export facility are scheduled for completion in 2030 - 2031.

While financing is not yet in place, Dunleavy is highly optimistic.

"We have all the permits, feedback from all the court cases, the support of the President of the United States, and Asian allies that need gas," Dunleavy said.

Unlike the major LNG terminals in Texas and Louisiana, Alaska LNG can be delivered in a straight shot to Japan, Korea, India, and Southeast Asia without traveling through the Panama Canal.

The project, which was approved during Trump's first term as President, received Federal Energy Regulatory Commission authorization in 2020 and final legal approval in 2022 but was put on hold during the Biden administration. Trump signed an executive order during his first day in office called “Unleashing Alaska’s Extraordinary Resource Potential.” The executive order removed certain restrictions on drilling as well as barriers to the development of mining and timber resources imposed by the previous administration. After more than 10 years of planning and permitting, it looks like the Alaska LNG Project could become a reality. Stay tuned.

“Build Baby Build” has brought about the remake of the energy transition to the energy addition.   

Conference Coverage

CERAWeek 2025 by S&P Global—‘Build Baby Build’

MTU Maintenance is constructing a new maintenance, repair, and overhaul (MRO) production section at its Berlin-Brandenburg location, supporting a 30% increase in shop visit volumes in the coming years. The German location services GE Aerospace’s LM-series aeroderivative industrial gas turbines (IGT), specifically the LM2500, LM6000, and other models. This expansion aims to improve workscope customization, satisfy customer requirements, and meet growing market demand.

“The demand for IGT maintenance is there, so I am quite confident we will achieve our goal of 30% more engines coming through our doors,” said Henrik Harksen, Director of Sales for IGTs, MTU Aero Engines. “This is why we have boosted our sales force and presence in local market segments across the globe.”

The new addition is slated to commence operations in January 2027 after completion.

In 2024, MTU Maintenance Berlin-Brandenburg purchased an existing structure next to its facility, which is now being demolished to accommodate a 113,000-square-foot MRO and business development expansion. The new production hall will house:

40 additional aeroderivative engine experts

The shop hosts an engine dock for rapid maintenance and turn arounds, and the apprentice workshop falls under a new training center to train and qualify mechanics. MTU Power’s expansion is designed to strengthen its independent LM-series MRO services.

“The aeroderivatives program is a crucial part of the success of MTU Maintenance Berlin-Brandenburg,” said André Sinanian, Managing Director and Senior VP of MTU Maintenance Berlin-Brandenburg. “The new maintenance facility is the continuation of a plan to modernize and expand the location, and to set it up for the coming decades.”

The location offers customized MRO solutions for additional regional aircraft engines, such as the CF34-8, CF34-10E, CFM56-7B, as well as Pratt & Whitney Canada’s PW200, PW300, and PW500. In 2024, MTU upgraded a test cell with advanced testing equipment and software to meet its CFM56-7B ramp-up operations. Over the last 30 years since LM-based MRO activities began, the site has completed over 1,500 shop visits.

 extension with Equinor ASA for MRO work on its LM-series industrial gas turbines. MTU Power will service Equinor’s fleet of GE Vernova Gas Power LM2500 and LM6000 industrial gas turbines until 2028. The MRO contract was initially signed in 2015 and, in addition to turbine servicing, it also entails offshore field service support, piece part repairs, and in-country level 2 maintenance, including module swaps and smaller work scopes.

Also in April, MTU Maintenance Berlin-Brandenburg 

 by Luftfahrtbundesamt, the German aviation authority, for the next steps in obtaining its CFM56-7B test capabilities. And MTU Maintenance Dallas received approval, from the Federal Aviation Authority, to test the engine model after a successful correlation of its test cell.

The test cell approval (for its location south of the German capital) completes its CFM56-7B portfolio expansion so that the Berlin-Brandenburg location can conduct the full range of MRO workscopes on the engine model, including testing, at one site. MTU Maintenance also announced its plans to expand its global ON-SITE

 service activities. The company is integrating its on-site services by creating a central unit that will oversee and steer the global network of MRO response teams.

The new industrial gas turbine field-service shop will house an engine dock and apprentice workshop to train and qualify mechanics.

Sultan Al-Shneiber & Rami Al-Shneiber

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