The Energy Centrist: Blog by Geoscientist Jason Eleson: Review

      This is an interesting blog by a senior geologist specializing in CCS and decarbonization. I have attended one of Jason’s excellent webinars on CCS geology, engineering, and economics. One thing that makes the blog interesting is that he will take an energy topic, current event, policy, or controversial subject, and try to analyze it and see it from three perspectives: left, right, and center. The blog is very informative and makes a good attempt to see the subjects from each perspective.

     The post on grid-scale batteries is great and digs pretty deep, giving up-to-date, realistic information about the advantages and limitations of batteries, covering costs, safety, environmental impacts, and geopolitics. Eleson gives a format to each post that acts as a comprehensive standard for evaluating the merits of a technology from a wide variety of perspectives. This includes standard headings such as Nutshell, Overview, Arguments For, Centrist Arguments, Arguments Against, Notable Quotables, Watt We Don’t Know, Our Take, Points to Ponder, What Happens Next, and Dig Deeper. It’s really a great way to organize these topics, which often have lots of pros and cons.

     The Energy Centrist is a blog by a smart guy with nuanced and evolved views of the subject matter. It seems to me to be a very good way to organize arguments and set up debates about the subjects. This is a well-thought-out energy analysis with limited bias that deserves more of our attention. I believe that such an approach will help us solve our energy problems rather than endlessly debate them based on partisanship.

     The blog is hosted on Substack for free, with donations accepted. We really need more perspectives and blogs like this. It sure beats all the heavily biased perspectives that are out there.

     Subjects covered so far in the Energy Centrist blog include batteries, natural gas powering data centers, the GHG reporting rollback, the ‘Endangerment Finding’ rollback, Atlantic hurricanes, wind power in the Trump era, small modular nuclear reactors, the attempted revival of coal power, and Chris Wright’s attempt to rewire the DOE.

     In his post about the greenhouse gas reporting rollback. Eleson warns that it is probably not a good idea. I mean, it is hard for scientists to support things like making data unavailable since it is data that supports conclusions. The idea of no longer tracking emissions, no longer collecting data on them, cannot be seen as a good move by most scientists, simply due to the fact that it decreases our knowledge about what is going on:

“Lee Zeldin has made many large, permanent structural changes during his short time at the EPA, but this one could come back to haunt him. Just as loss of wind and solar jobs will be felt by communities that had IRA-backed funding disappear (with little prospect of comparable replacement industries or jobs), so too it may be the proposed GHGRP repeal. Ironically, some of the biggest protests may come from oil and gas companies that are seeking to showcase and quantify their recent GHG reductions from things like efficiency improvements, displacing coal with natural gas as the powerplant fuel of choice and being leaders in the CCS movement. If Mr. Zeldin wants to do repeal GHGRP requirements, we believe he should be more transparent about his motives. It seems as if his primary motivation stems from a lack of concern or belief in climate change, or the negative impacts associated with it. If so, he should lead with that and keep the cost savings as a secondary goal. Other reforms he has undertaken could genuinely improve the growth prospects for many industries in the US…this does not appear to be one of them.”

This blog is highly recommended!

 

   

 

References:

 

Backup Plan or Blind Spot? The Battery Bet Revolutionizing Power: Can advanced batteries make renewable energy dependable—and affordable—for all? The Energy Centrist. Jason Eleson. September 28, 2025. Backup Plan or Blind Spot? The Battery Bet Revolutionizing Power

Turbines, Tech, and Trade-Offs: The electrifying debate over the role of natural gas in powering tomorrow's data centers. The Energy Centrist. Jason Eleson. September 21, 2025. Turbines, Tech, and Trade-Offs - The Energy Centrist

GHG Reporting Rollback: EPA'S $2.4 Billion Emission Omission: Weighing regulatory relief against the cost of losing America’s carbon compass. The Energy Centrist. Jason Eleson. September 13, 2025. GHG Reporting Rollback: EPA'S $2.4 Billion Emission Omission

 

 

Solar is a Doubled-Edged Sword in Pakistan as it Helps Farmers but Raises Power Prices and Accelerates Groundwater Depletion

     Solar-powered irrigation pumps are becoming a successful trend in Pakistan. One old farmer in the Punjab region referred to it as a “societal revolution” not seen since Pakistan built its highway system about four decades ago. Solar generation has grown manyfold in Pakistan, now accounting for nearly one-half of grid power. The boom was triggered by lower solar panel costs from Chinese imports and government subsidies. It has allowed many Pakistani households to go off-grid completely, although many stay grid-tied to take advantage of net metering, where they can sell their excess power back to the grid. The Pakistani power grid is aging, overburdened, and costly. Electricity prices doubled between 2021 and 2024, before the government stepped in to stabilize them.

“Elsewhere in the sane world as in Pakistan, ordinary people have taken matters into their own hands, putting up rooftop solar power on individual homes now equal to one-half of the country’s electric grid. The biggest solar adopters are farmers, using solar to replace diesel fuel to power field generators for water irrigation. As a result, Pakistan used 35% less diesel fuel last year than the year before.”

     An emerging issue is that while wealthy consumers tend to go solar, poorer residents must absorb a higher percentage of the higher power costs. After decades of power shortages, Pakistan now has an excess of power plants, after building several new coal-fired plants since 2010. The solar boom in Pakistan appears to be mainly a rooftop solar and solar irrigation boom. Generous subsidies, some at 60%, are fueling the boom. Apparently, it is simply a better deal than connecting to the grid, which, for rural customers, means additional costs like purchasing transformers.

     Among those connected to the grid, the high power costs force some people to choose between food and power. High temperatures in the country make some kind of cooling, whether via fans or air conditioners, very desirable. Pakistan’s net metering policy, where it pays grid-tied solar customers for their excess power, has led to financial losses due to too much excess power. The situation also shows an inherent flaw of availability in solar subsidization – that the wealthy, those who can afford the upfront costs, will benefit the most. That has definitely been the case in Pakistan as elsewhere. In a sense, it exacerbates inequality by extending opportunities to the wealthy that the poor cannot afford.

     Proposed solutions include promoting and subsidizing battery systems, more government investment in solar, limits on the sizes of solar systems, and grid modernization.

     Another trend among Pakistani farmers is solar-powered tube wells, where solar energy powers the well pump. This is creating more opportunities for farmers. It has resulted in 30% more rice farming and 10% less maize farming from 2023 to 2025. In the drought-prone region of the Punjab, there are dried riverbeds. Growing less water-intensive crops, such as rice, would be better since drops in the groundwater table have been associated with the solar-powered tube well boom. These tube wells do not require permits or registration, so it is unknown how many there are. There must be quite a few since it is expected that the amount of grid electricity consumed by the agricultural sector is expected to drop by 45% from 2023 through 2025. An advisor to Pakistan’s energy minister, Amar Habib, renewables analyst Syed Faizan Ali Shah, and Reuters calculated that 400,000 tube wells were converted from grid power or diesel to solar, and 250,000 new ones were drilled since 2023, suggesting a total of 650,000 tube wells.

     According to Reuters:

“The water table has shrunk below 60 feet - a level designated as critical by the provincial irrigation department - across 6.6% of Punjab as of 2024, according to maps published for internal use by water authorities and seen by Reuters. That marks an increase of some 25% between 2020 and 2024, while the deepest pockets - with water levels beyond 80 feet - more than doubled in size during the same period.”

     Reuters also noted that Pakistan’s energy minister, Awais Leghari, disagreed that solar pumping was depleting groundwater, citing the fact that the same amount of land was under cultivation. However, he did not respond when asked about the growth of rice farming. Low wheat prices have stressed farmers in the region and put pressure on them to grow more profitable crops. Farmers are also banding together to purchase solar panels in a community solar type of approach.

"Farmers share, rent and move panels like tractors," said Lahore-based solar-panel merchant Shahab Qureshi. "They sell land, jewellery, or take loans just to get it. Within five to six months, your return on investment is fulfilled."

     Punjab is piloting about 40 groundwater recharge projects, which have increased in importance since India signaled it would restrict the sharing of Indus River water earlier this year. Farmers are also hoping to increase surface water irrigation projects and utilize older infrastructure, such as old siphon tunnels, to access more water and lessen the load on groundwater resources. What Pakistan does not have is a detailed mapping of water wells and quantitative data on water withdrawals. For sure, groundwater depletion in the region is a problem to be monitored and mitigated.

   

References:

 

How Pakistan’s solar energy boom led to higher power bills for the poor. Rick Noack and Shaiq Hussain. Washington Post. August 24, 2025. How Pakistan’s solar energy boom led to higher power bills for the poor

Clean Solar Outshines Filthy Oil. Robert Hunziker. Z Network. September 2, 2025.  Clean Solar Outshines Filthy Oil

Solar-powered farming is digging Pakistan into a water catastrophe. Ariba Shahid. Reuters. October 1, 2025. Solar-powered farming is digging Pakistan into a water catastrophe

 

Coal Nostalgia by the Trump Administration is Likely to Be Short-Lived Due to Future Political Control and Regulatory Uncertainty

     By short-lived, I mean when the administration encounters loss of political control from Congress and eventually the presidency, which I believe will happen. The current administration is enacting policies and executive orders as if those will never be rolled back. By the time some of the policies are enacted, such as producing more coal, they may be facing rollbacks. While there is certainly some concern about future power reliability due to the loss of baseload power generation sources, including coal, especially in light of increasing projected power demand, it is unlikely to mean a revival in coal production and coal-fired plant upgrading. There will, however, likely be more coal plant retirement delays. I don’t think the power industry believes a coal revival in power production is likely.

     The Trump administration announced recently that it will open 13 million acres of federal lands for coal mining and provide $625 million to recommission or modernize coal-fired power plants. The plan for the spending is shown below.

     The call to ‘mine, baby, mine’ echoes the call to drill, baby, drill, which has not resulted in any drilling growth over the last eight and a half months. The so-called ‘Big Beautiful Bill’ lowered federal royalty rates for coal mining from 12.5% to 7%, a significant decrease that officials said will help ensure U.S. coal producers can compete in global markets. Interior Secretary Doug Burgum noted:

“By reducing the royalty rate for coal, increasing coal acres available for leasing and unlocking critical minerals from mine waste, we are strengthening our economy, protecting national security and ensuring that communities from Montana to Alabama benefit from good-paying jobs."

     The DOE also listed all the actions they have initiated to support America's coal industry:

     EPA administrator Lee Zeldin suggested it was heavy-handed regulations from the Biden administration that hurt coal, but that argument has been debunked, including by centrist conservatives such as Benji Backer, who wrote an op-ed to argue that it was market forces that caused coal use to drop.

     The EPA also announced that it will delay seven deadlines related to wastewater pollution from coal-fired power plants. The rule on coal residuals (CR), or coal ash left over from burning the coal, which sits in giant piles of sludge in unlined ponds, will be delayed. Coal ash has been found to pollute local groundwater with toxic heavy metals wherever it is stored in such a way.

     Two coal plants in Ohio, near where I live and likely where my power comes from, have some of the biggest unlined coal ash piles. These are very old plants; one was built in 1954 and one in 1974-75. While they have been modernized to some extent with pollution control equipment, they are surely getting close to the end of their lifetimes. I actually interviewed for a job at the older of the two plants a few years ago, but was not selected. One plant has been associated with several events where black soot was spread all over the immediate region. Local people were very concerned. Eventually, the power company bought out many of the local houses in the town of Cheshire, which is much diminished now. 

     When the second Trump administration began, those plant owners were given new hope for continued operations.

“We just feel like the last administration, all of these regulations were really designed to force the closure of coal plants,” said Michelle Bloodworth, president and CEO of industry group America’s Power.

     According to an April 2025 AP article by Michael Phillis:

“Environmentalists worry about coal ash and its heavy metals in part because there’s so much of it – more than 100 million tons is produced each year, much of which sits near lakes and rivers in sprawling disposal sites. Some is reused, but a lot is stored near coal plants in coal ash ponds that may not have a lining to keep it from leaching into groundwater.”

“It can be disastrous when companies fail to keep that waste in place. In 2008, a huge dike burst at a Tennessee coal plant. That released more than a billion gallons of coal ash, polluting rivers, toppling homes and shortening the lives of many cleanup workers who spent months exposed to its toxicity.”

“That disaster helped lead to the first federal standards for coal ash disposal in 2015. Those included requirements for companies to line new storage sites, conduct water monitoring and ensure many leaky ponds closed safely, often requiring the material to be moved elsewhere.”

“It contains a lot of important protections, but it didn’t apply to all the coal ash that utilities were managing,” said Nick Torrey, an attorney with the nonprofit Southern Environmental Law Center.

     The 2600 MW Gavin power plant was sold in late 2024, from one private equity owner to another, which I posted about. It became operational in 1974-1975. According to the Sierra Club, it is the plant they associate with the most deaths from pollution in the country, as well as fifth in CO2 emissions among power plants. It is the largest emitter of PM 2.5 particulate matter from a single source in the U.S. Lucky for me, the air blows the other way. Energy Secretary Chris Wright recently echoed Trump in referring to coal as “beautiful, clean coal.” While its beauty is debatable, it is not clean.

“The EPA estimated Biden’s rules would cost the industry as much as $240 million annually. America’s Power says forcing plants like Gavin to remove coal ash that sits below the water table that they don’t believe is a significant threat to the area’s groundwater and drinking water is extremely costly and can force shutdowns.”

     Matthew Daly of AP writes:

“Coal once provided more than half of U.S. electricity production, but its share dropped to about 15% in 2024, down from about 45% as recently as 2010. Natural gas provides about 43% of U.S. electricity, with the remainder from nuclear energy and renewables such as wind, solar and hydropower.”

“Energy experts say any bump for coal under Trump is likely to be temporary because natural gas is cheaper, and there’s a durable market for renewable energy such as wind and solar power no matter who holds the White House.”

     The notion of using coal to power AI is both nostalgic and dangerous. Projected data center load growth is not just from AI, but nearly one third of it (about 30%) is projected to be to power cryptocurrency. The notion of polluting people to provide transaction security that benefits criminals (crypto is a favorite of money launderers) and stock speculators seems beyond nostalgic to me. It seems almost diabolical in the sense that there are better ways to provide transaction security and better ways to expend energy. We have plenty of natural gas, especially here in the Midwest/Northeast, that can be used for power plants and AI that is cheaper than coal, except during cold snaps when inadequate pipeline capacity and other infrastructure like gas storage fields become temporarily unavailable. We really don’t need coal for power and AI. Meanwhile, environmentalists continue to pursue the denigration of natural gas, which is much cleaner and more often cheaper than coal.  

 

 

    

References:

 

Trump administration opens more land for coal mining, offers $625M to boost coal-fired power plants. Matthew Daly. Associated Press. September 29, 2025. Trump administration opens more land for coal mining, offers $625M to boost coal-fired power plants

Energy Department Announces $625 Million Investment to Reinvigorate and Expand America’s Coal Industry. U.S. Dept, of Energy. September 29, 2025. Energy Department Announces $625 Million Investment to Reinvigorate and Expand America’s Coal Industry | Department of Energy

Burning coal leaves dangerous waste. Trump’s EPA eyes looser rules for handling it. Michael Phillis. Associated Press. April 16, 2025. Burning coal leaves dangerous waste. Trump's EPA eyes looser rules for handling it | AP News

 

 

Underground Pumped Hydro Energy Storage: Chinese Researchers Evaluate Henan Province Coal Mines for Pumped Hydro Potential: Scientific Paper Review & Summary

     This research from China, published in Energies in June 2023, evaluates the use of existing coal mines in Henan Province for potential underground pumped hydro energy storage (UPHES). The study calculates the space available and the suitability for pumped hydro. This is a detailed study that develops a site selection methodology that compares and high-grades sites, mining trends, the history of underground pumped hydro, and the utilization of mined-out space are all explored.

     The paper first points out China’s large coal consumption, which makes up about 56% of the country’s primary energy consumption and 80% of its carbon emissions.

 

Figure 1. Annual coal production, consumption, and CO2 emissions from coal in China. (Data source: Our World in Data [8] and China Statistical Yearbook 2022.

 

     The authors note that there are now many closed and abandoned coal mines in China with space for underground pumped hydro energy storage (UPHES) applications. Past UPHES studies in China have focused on technological feasibility, environmental impact, and economic analysis. This paper focuses on site selection. Considerations include local geology and hydrogeology. Previous studies revealed that the permeability coefficient and horizontal distance were two factors necessary for site evaluation. Above-ground PHES projects require topography with significant elevation change, but UPHES can be developed without regard to topography.

     The authors developed a two-step site selection process. The first step involves a screening assessment that evaluates the geology and hydrogeological conditions. Step two is a comprehensive assessment that involves an analytic hierarchy process (AHP).

     The section on coal industry trends in China notes that there are predictions that China’s coal consumption for both power and industry will peak before 2030.

 

Figure 2. (a) Primary energy consumption in China by fuel type. (b) Primary energy consumption of several countries in 2021. (Data source: BP Statistical Review of World Energy).

 

Mined Underground Space Utilization

     It is predicted that by 2030, there will be 15,000 closed or abandoned coal mines in China. The space available in these mines includes deep shafts, extensive drift networks, and goaves. The utilization of underground mine space includes four main modes: energy storage, waste disposal, ecological restoration, and CO sequestration.

“Pumped storage is widely regarded as one of the most reliable, cost-effective, and mature technologies for large-scale energy storage, and it holds great promise for implementation in old coal mines. The process of coal mining naturally forms large quantities of underground caverns, which can serve as ready-made reservoirs with significant elevation differences, making them ideally suited for pumped storage. Moreover, the restored surface areas of old coal mines can be effectively repurposed as sites for wind and solar farms, ensuring a sustainable and renewable power supply for UPHES. This integration of renewable energy generation and energy storage unlocks new opportunities for the coal industry. Most UPHES projects are designed as closed-loop systems, operating independently from naturally flowing water bodies. This design allows the direct utilization of mine water as a supplement, mitigating the risk of water contamination and preserving water resources.”

     The Nassfeld power plant in Austria has long utilized UPHES. The plant has a surface water body and some excavated caverns as well as mine space. The geology of impermeable granite and gneiss, igneous and metamorphic rocks, provides good containment for water.

 

Site Selection

     As noted, economics, social, and environmental factors are important for UPHES site selection, as well as geology and hydrogeology. The presence of nearby surface wind and solar facilities to charge the system by powering the hydro pumping is another consideration.

     The step 1 screening assessment involves calculation and consideration of gross head, head-distance ratio, and water source. These data are integrated with geology and hydrogeology conditions. There are three screening indicators: geological features, mine water disasters, and minimum installed capacity. Geological features include the presence of karst geology, which is vulnerable to dissolution and would make the site unsuitable for pumped hydro. Consideration of mine water disasters includes a mine’s vulnerability to inflow greater than 600 cubic meters per hour, which indicates unacceptable hydrogeologic conditions. Such inflow can reduce power production capacity and involve more pumping, which makes economics more difficult. A minimum installed capacity of 20 MW was determined to be the cutoff for the screening assessment.

     The Step 2 comprehensive assessment involves determining the surface availability of wind and solar resources and the conditions of the local power grid, where pumped hydro could provide peak shaving services during high power demand times.

     Gross head refers to the elevation difference between the upper and lower reservoirs. Effective reservoir volume refers to the amount of water that can be stored in both reservoirs. If the surface water and groundwater are well connected and interactive, then this could lead to problems, which makes such sites unsuitable. The underground space must also be geologically stable, and the disaster potential must be low. Permeability of the surrounding rock must be considered. Hydraulic conductivity that is too high, combined with a high groundwater head can result in unsuitable conditions due to the lower reservoir filling too fast. The power regulation potential of UPHES requires the facilities to be near urban centers where power demand peak shaving is most needed. Being near urban centers also helps employment. Local support for projects can also be important.  Other considerations include the cost of energy storage, the payment potential of providing peak shaving services in the form of peak-to-valley tariff differential, maintenance and monitoring costs (some mine water is corrosive due to water chemistry), and the integrity of remaining equipment, including transportation and communications equipment and substations.  

     The analytic hierarchy process (AHP) includes weight calculations of many of the above factors to rank site suitability. This is a statistical method that involves the creation of a hierarchy, the construction of comparison matrices, and calculating priority and consistency.

“By weight calculation, indicators that have significant influences over site selection are identified, including the gross head (C11), the effective reservoir volume (C12), the local peak-to-valley tariff differential (C42), the unit cost of energy storage (C41), the stability of the underground space (C14), and the local power demand (C21). These indicators play crucial roles in determining the technical feasibility, safety, and economic viability of UPHES projects in old mines.”

     Next is a case study comparing three sites in Henan Province. The first table is data for the screening assessment, and the second table is the AHP conclusions for the comprehensive assessment.

     Henan Province has a growing number of closed and abandoned mines as coal production from that region continues to drop.

 

Estimation of Underground Space in Coal Mines

     Determining available space in mines involves estimating the volume of drifts, chambers, shafts, and goaves. Goaves are less stable since they don’t have ventilation and supporting structures. The authors show how a capacity coefficient was developed in a previous study to estimate space volume. Some of the mathematical variables in this calculation are the volume of mined coal, the determination of volume reduction due to surface subsidence, and the determination of volume reduction due to rock expansion after pressure relief.

 

UPESH Potential Estimation

     Estimating the UPHES potential of a mine site involves knowing two crucial factors: effective reservoir volume and the elevation difference of the upper and lower reservoirs.

“The effective reservoir volume and the elevation difference between the upper and lower reservoirs are two crucial factors in determining the installed capacity, power generation and economic profitability of a pumped storage power plant.”  

     Effective reservoir volume estimation must account for space that is ineffective and conditions like reverse slopes that will affect gravity feed and reduce circulating volume if there are cutoff stagnant zones. Groundwater inflow that is too high will result in filling the lower reservoir prematurely. This could reduce the amount of water available for discharge.

     The elevation difference between upper and lower reservoirs, also known as the head height, should optimally be between 200m and 800m. Henan Province mines have head heights between 300m and 1200m with an average just greater than 600m, which are considered very good.

“When the head height is less than 200 m, both the efficiency and economic benefits of the power plant significantly decrease. On the other hand, when the head height exceeds 800 m, the current Francis turbine is unable to meet the high-pressure requirements. Thus, multi-stage pumped storage power plants with intermediate storage reservoirs are regarded as an alternative.”

     If only one coal seam has been mined, then the depth to the mine from the surface constitutes the head height since the upper reservoir in that case will likely be a surface water body. In that case, it is termed a semi-underground PHES. If two or more coal seams are mined, the head height can be the elevation difference between the two seams. This is termed a fully underground PHES and is the preferred configuration. It is also much rarer, as the following table for Henan Province shows. The other tables show the potential for each scenario.  

     The final section involves estimating the decarbonization potential of UPESH projects, which depends on how much curtailed or dedicated solar and wind power is provided. UPESH projects can eliminate most curtailments, increasing emissions reduction further than just the discharging of hydro energy production, but also incorporating it into charging.

“In 2022, wind and solar power curtailment rates in Henan Province were 1.8% and 0.5%, respectively. Accordingly, the abandoned wind and solar power during the year amounted to 686.7 GWh and 102.9 GWh, respectively. The surplus power can be consumed by UPHES power plants, with about 631.7 GWh of energy successfully stored (assuming the plant efficiency of 80%). There is enough UPHES potential in existing old coal mine drifts to handle this surplus power, as mentioned above.”

“…by consuming surplus renewable energy, UPHES can reduce about 7.11 × 105 tonnes of CO2 emissions in 2025.”

     The authors note that their two-step site selection process basically adds the screening assessment to the previous process, which is basically the comprehensive assessment. By screening out unlikely candidates based on the three criteria of geological features, mine water disasters, and minimum installed capacity, which effectively characterize geological and hydrogeological conditions, effective reservoir volume, and head height, the process is streamlined and becomes more reliable and effective. The paper’s conclusion that the volume of goaves, areas of space filled with caved rock, is much higher than that of drifts and shafts suggests that if the goaf space can also be utilized, it could drastically increase the amount of UPESH potential for a given mine.

     The conclusions of the paper are given below:

 

 

References:

 

A Two-Step Site Selection Concept for Underground Pumped Hydroelectric Energy Storage and Potential Estimation of Coal Mines in Henan Province. Qianjun Chen, Zhengmeng Hou, Xuning Wu, Shengyou Zhang, Wei Sun, Yanli Fang, Lin Wu, Liangchao Huang, and Tian Zhang. Energies 2023, 16 (12), 4811, June 2023. A Two-Step Site Selection Concept for Underground Pumped Hydroelectric Energy Storage and Potential Estimation of Coal Mines in Henan Province

 

 

Electrical Submersible Pump Optimization in Gas-Rich Unconventional Oil Wells

      Electrical submersible pumps, or ESPs, are ubiquitous in oil production applications. This post is a summary of two articles in World Oil’s June 2025 issue, one by personnel from Baker Hughes about the performance and lifespan benefits of its boosted gas separator, and the other by NOV personnel about the reliability benefits of its new gas processing system. Both innovations are applicable to gas-rich oil wells that can be problematic for pumps.

 

Baker Hughes Boosted Gas Separator

     The authors from Baker Hughes note that its new boosted gas separator can:

“…enhance fluid production, improve reservoir recovery and enable operational flexibility. In turn, this enables safer, more efficient and more profitable operations.”

     When bottomhole pressure drops, gas can interfere with pump operation. This is especially problematic in oil wells with high gas-to-oil ratios (GORs). Thus, there is a need to address high Gas Volume Fraction (GVF) conditions in ESP systems. Problems include cycling, gas locking, and pump wear. The problems are most apparent in the Permian and Bakken. Baker Hughes offers what they call a system-level solution:

“…a fully integrated system that combines multiple technologies to manage gas effectively and maintain flow stability. Vortex-style gas separators use centrifugal action to separate higher-density fluids from lower-density gas, which is then vented back to the wellbore. This prevents free gas from entering the pump intake. Gas handling and multiphase pumps improve system performance by compressing the gas-liquid mixture, reducing bubble size and preventing gas lock. These multiphase helio-axial stages can effectively handle mixtures with gas volume fractions (GVFs) up to 75%, maintaining high boost pressure while increasing the fluid density delivered to the upper pump stages.”

“In a standard ESP configuration, fluid flows directly through the gas separator before entering the pump stages. In a system that incorporates a boosted gas separator, the fluid is introduced through an intake, where it is compressed by a gas handler pump before entering the separator, which enhances recirculation. The pre-compressed fluid is then routed to the gas separator, before reaching the lift pump. This process improves gas separation by diluting the gas concentration and stabilizing flow, with pressure losses in the annulus offset by inducer-generated lift.”

 

Fig. 1. Standard configuration vs. boosted gas separator, where pre-compressed gas improves separation.

 

     Another innovation now in common use is permanent magnet motors to run the ESPs, which results in vastly improved efficiency. I wrote about permanent magnet motors in oilfield applications a few months ago.

     Another design enhancement has been the use of computational fluid dynamics (CFD), which enables modeling, simulation, and validation under different configurations.

“The most notable improvements in separator efficiency were observed at liquid rates above 2,000 bpd, representing a typical 40% increase over traditional gas separators. This improved separation enables ESPs to sustain a throughput of 3,000 bpd, while achieving bottomhole pressures as low as 1,000 psi, in wells producing more than 1,000 MMscfd. As a result, drawdown and production are maximized in high-GVF unconventional environments.”

 

Fig. 3. CFD analysis shows that adding a booster pump improves gas separation and sends more liquid to the pump across all GVF levels.

 

     Baker Hughes has been field testing this boosted gas separator since October 2021, with the pump achieving 934 run days. They now have 136 ESPs in the Permian Basin and 146 in other places around the world, with the separator installed. These are installed in wells with variable production rates and variable GORs. One well showed increased production of 500Bbls per day over 60 days. The chart below shows performance improvements of the boosted gas separator over gas lift, a common method of artificial lift that injects gas into the production tubing to reduce fluid density and help bring hydrocarbons to the surface.

 

Fig. 4. This chart shows the average oil production before and after ESP installation, demonstrating that installing ESPs in these six wells increased oil production in all of them by an average 90%.

 

     A new multiphase ESP system has improved production in wells susceptible to gas slugs. Gas slugging can result from undulations in well laterals, including land the well unintentionally below the target zone and coming up into it, creating a sump effect at the beginning of the lateral. Gas slugging can lead to gas lock, frequent pump cycling, and motor overheating. The multiphase ESP system is installed in 1300 locations in the U.S. and combined with the boosted gas separator, PMMs, and an efficient gas handling pump, it can lead to significant production increases. These solutions will remain important as the amount of associated gas from oil wells continues to increase.

     The authors also note some future innovation projects:

“Innovations like the FusionPro—an advanced variable speed drive that incorporates sophisticated controls specifically designed for gassy environments—are in development, along with a boosted gas separator system for high-temperature applications and a next-generation gas separation technology, offering improved gas handling capabilities, set to launch later this year.” 

 

NOV’s Integrated Gas Processor (IGP) Improves Artificial Lift and Pump Reliability

      National Oilwell Varco, or NOV, also addresses gas interference in high GOR oil wells with its Integrated Gas Processor (IGP). The first schematic below depicts a typical ESP configuration, and the second one depicts an IGP configuration. The IGP system replaces the gas handler and the gas separator. The IGP combines those into one highly efficient unit. The traditional design can prevent operators from reducing the pump intake pressure (PIP), which can prevent pump optimization and the associated production increases.  

 

Fig. 1. A typical ESP installation includes a tandem gas separator and gas handling pump.

 

Fig. 2. The IGP replaces the gas separator and gas handler.

 

“The IGP operates differently from traditional gas handling equipment. Fluid enters a high-volume flow intake and goes into the lower module, where proprietary Contra-Helical Pump (CHP) stages compress and condition (homogenize) the gas and liquid. Unlike a traditional centrifugal pump, the CHP provides two flow paths that allow gas to flow into both the rotor and stator. The primary flow path is the helical flow, while the secondary flow path is the fluid vortex, generated within the rotor and the stator vanes. As a result, the CHP can ingest and condition a higher amount of gas, as it moves through the pump. Moreover, conditioning the gas provides buoyancy to the production fluid, increasing overall lift efficiency.”

“Then, the more homogenized gas-liquid mixture enters the center module that features a dual-chambered gas separator, which is strategically positioned to reduce gas recirculation and enhance gas separation efficiency. An inducer rotates the fluid at high speed, causing the high-density liquid to move to the outer diameter, while the low-density gas concentrates toward the inside diameter. A crossover component diverts the free gas to the exit ports and out into the annulus of the well, between the IGP and casing wall, and directs the liquid into the next stage of separation. This process repeats in the second stage of separation, further reducing the GVF {gas void fraction} and directing the fluid into the upper module.”

“Finally, the fluid enters the upper module for further compression and conditioning, before moving into the primary production pump. Both CHP and centrifugal style stages are available for the upper module.”

     The tree-module system is shown below:

 

Fig. 3. The three-module, all-in-one housing system is designed to separate and prepare the gas before entering the ESP’s primary production pump.

    

  

   Below, the authors give a case study example from the Delaware Basin, showing clear production improvements:

“The IGP exceeded the previous gas handling equipment, leading to a rapid rise in fluid production. Oil production rose 153%, from 136 bpd to 344 bpd, while gas production increased 224%, from 202 Mscfd to 654 Mscfd. Water production also increased 316%, from 417 bpd to 1,734 bpd, which led to a 14% reduction in the GLR, from 365 scf/bbl to 315 scf/bbl. Meanwhile, the PIP immediately dropped 11%, from 579 psi to 514 psi.”

 

Fig. 4. After installing the IGP, the Permian operator saw an immediate increase in production and a decrease in GLR and PIP.

    As in the Baker Hughes example, the IGP showed a marked performance improvement over gas lift. Downtime was reduced as well. As GORs continue to increase over time in the Permian Basin, these solutions will be deployed more and more. Longer laterals and undulating laterals will also benefit from these solutions.

“More than 120 IGPs have been installed in unconventional wells across the U.S., tackling the persistent challenge of gas interference. By integrating critical gas handling functions into a single, modular and optimized system, the proven IGP is poised to drive a new era of enhanced production, as well as substantial improvements in operational safety, efficiency and reliability.”

 

 

    

References:

 

Boosted gas separator enhances ESP performance, extends service life in gassy, unconventional wells. JOSEPH MCMANUS, MOHAMMAD MASADEH and OSCAR PADILLA, Baker Hughes. World Oil. June 2025. Boosted gas separator enhances ESP performance, extends service life in gassy, unconventional wells 

New gas processing system enhances electrical submersible pump reliability. AMES RHYS-DAVIES and JESSICA STUMP, NOV. World Oil. June 2025. New gas processing system enhances electrical submersible pump reliability