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Quality Guidelines for Energy System Studies: Cost Estimation Methodology for NETL Techno-economic Assessments

This Quality Guidelines for Energy System Studies (QGESS) summarizes the methodology employed by the National Energy Technology Laboratory (NETL) in calculating plant costs in its techno-economic studies, such as the Cost and Performance Baseline for Fossil Energy Systems series of reports. It also outlines the approach used to calculate the cost of electricity (COE) or cost of product (COP) metrics by which NETL estimates the impact of technology options. These metrics and a clear understanding of the methodology used are essential in allowing different plant technologies to be compared on a similar basis. These guidelines were initially developed for power producing plants, although they can be applied to a variety of different revenue generating plants (e.g., coal to liquids, syngas generation, hydrogen) by substituting the industrial product quantity for the electrical quantity in the equations. The tables contained in this QGESS have been expanded upon relative to previous versions to include values to assume for several industries.

20 FOSSIL-FUELED POWER PLANTS↗

Quality Guidelines for Energy System Studies: Process Modeling Design Parameters

The National Energy Technology Laboratory (NETL) conducts systems analysis studies that require a large number of inputs, from ambient conditions to parameters for Aspen Plus ® (Aspen) process blocks. The sheer number of assumptions required makes it impractical to document all of them in each issued report. The purpose of the Quality Guidelines for Energy System Studies (QGESS) is to document the assumptions most commonly used in system analysis studies and the basis for those assumptions. In order to develop the systems analysis models presented in various NETL reports, significant vendor data have been obtained, and these data enhance the model outputs. Much of the vendor data obtained are considered proprietary and not suitable for public release or attribution to a specific vendor. As such, several sub-systems common in NETL reports and their process parameter data are not reported in this document to protect proprietary vendor information. The values and ranges of values presented in this report represent assumptions that have been made in previous studies.

97 MATHEMATICS AND COMPUTING↗

Quality Guidelines for Energy System Studies: Capital Cost Scaling Methodology: Revision 4b Report

The National Energy Technology Laboratory (NETL) regularly updates legacy analysis with new studies and cases as the Department of Energy objectives change, technology performance improves, costs are reduced, regulations change, market drivers are established, fuel prices fluctuate, and any number of other relevant factors vary in the market. As legacy studies are updated by NETL, the underlying performance and cost of the cases presented changes, and as such, the methods for interpreting and scaling the cost estimates change. Therefore, it is important that NETL maintain public guidance documents associated with different sets of cost estimates that delineate how a specific set, based on report vintage and/or year published, should be scaled. This Quality Guidelines for Energy System Studies report, providing guidance on capital cost scaling, should generally be applied to NETL case costs included in the report “Cost and Performance Baseline for Fossil Energy Plants Volume 1: Bituminous Coal and Natural Gas to Electricity Revision 4b,” (NETL, 2025) or any cases derived from the cases presented in the referenced report.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Quality Guidelines for Energy Systems Studies: Cost Estimation Methodology for NETL Assessments of Power Plant Performance

This paper summarizes the methodology employed by the National Energy Technology Laboratory (NETL) in calculating power plant costs in its techno-economic studies, such as the Cost and Performance Baseline for Fossil Energy Systems series of reports. It also outlines the approach used to calculate the cost of electricity by which NETL evaluates electric power plants. These metrics and a clear understanding of the methodology used are essential in allowing different power plant technologies to be compared on a similar basis. These guidelines are tailored for power producing plants, although they can be applied to a variety of different revenue generating plants (e.g., coal to liquids, syngas generation, hydrogen).

20 FOSSIL-FUELED POWER PLANTS↗

Quality Guidelines for Energy System Studies - Capital Cost Scaling Methodology: Revision 4a Report

Costs are frequently required as part of systems analysis work at NETL. Many of the cost results provided as part of systems analysis work were created with the use of scaling, since obtaining new vendor-supplied cost quotes for each category developed by NETL would be prohibitively time consuming and costly. Additionally, many of the technologies being investigated by NETL have not progressed far enough to have quotable costs. The costs are scaled from a quote for a similar plant configuration by use of various equations that typically employ at least one process parameter (e.g., coal-feed rate, oxidant-feed rate) and often an exponent. The primary purpose of the exponent is to account for economies of scale (i.e., as equipment size gets larger, it gets progressively cheaper to add additional capacity). The purpose of this section of the QGESS report is to provide a standard basis for scaling costs, with specific emphasis on scaling exponents. The intention of having a standardized document is to provide guidelines for proper procedures to reduce the potential of errors and increase credibility through consistency.

99 GENERAL AND MISCELLANEOUS↗

Quality Guidelines for Energy System Studies: Performing a Techno-Economic Analysis for Carbon Conversion Technologies (Final Report)

This document provides DOE-FECM specific guidance for conducting techno-economic analysis (TEA) on carbon conversion technologies using NETL's established TEA methodology. The intent is to provide guidance to develop a consistent methodology for evaluating carbon conversion technologies within the DOE-FECM portfolio. The document provides guidance on the analysis methodology, evaluation metrics including performance, cost, emissions, and market considerations, and ample references to guide the end user in the development of consistent TEA of carbon conversion technologies.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Quality Guidelines for Energy System Studies: Carbon Dioxide Transport and Storage Costs in NETL Studies

Transport, storage, and combined T&S costs are reported in this guideline as first-year break even (FYBE) costs in real 2023 dollars per metric ton (tonne) (2023$/tonne). These FYBE costs are from the perspective of a CO 2 pipeline project owner and/or a CO 2 saline storage project owner, and represent a minimum price the owner(s) can charge a CO 2 capture project owner over 30 operating years to transport and/or store a tonne of CO 2 and remain economically viable.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Evaluation and calibration of MERRA-2 and CAMS reanalysis for PM 2.5 in a semi-urbanized area in the south of the Amazon

Air pollution has significant implications for the climate and poses irreversible risks to human health. The Amazon region of Brazil is severely affected by biomass burning (BB) emissions, yet air quality monitoring remains highly inadequate. Given the scarcity of surface-based observations, reanalysis models have become essential tools for assessing air pollution. Although MERRA-2 and CAMS PM 2.5 products are widely utilized, their validation and comprehensive evaluation for the Amazon Basin remain limited. Here, this study assesses the performance of these products in a semi-urbanized region in the southern Amazon. The calibrated time series was employed to analyze PM 2.5 concentrations from 2003 to 2023. Our results showed satisfactory performance of both products for the 24-h averages of PM 2.5 , with linear correlations above 0.76. However, it was found that both products overestimate surface concentrations. MERRA-2 performed better, with approximately 30% lower bias than CAMS. Time series analysis showed that the study area is strongly impacted by emissions BB in the dry period, mainly in August and September. Furthermore, our findings indicate a positive trend in increasing PM 2.5 concentrations, with a notable rise observed since 2014. The average PM 2.5 levels frequently exceed the daily air quality guidelines established by the WHO in 2021. It has been estimated that the population of this region is exposed to concentrations above 15 μg.m -3 , on average, more than 30 days per year. Our results contribute to the evaluation of MERRA-2 and CAMS products for Amazon and provide a corrected estimate for surface PM 2.5 . Recent concerns about air quality and the implementation of new surface monitoring networks may improve the evaluation of reanalysis products. In the short term, the need for this information makes our assessments indispensable.

54 ENVIRONMENTAL SCIENCES↗

Isotherm modeling and techno-economic analysis of a TSA moving bed process using a tetraamine-appended MOF for NGCC applications

Tetraamine-appended metal-organic frameworks (MOF) are a new family of amine-functionalized MOF materials that show potential for CO 2 capture from flue gas conditions relevant to natural gas combined cycle (NGCC) power plants. This work presents isotherm modeling of the tetraamine-appended MOF Mg 2 (dobpdc)(3-4-3)(dobpdc 4- =4,4'-dioxidobiphenyl-3,3'dicarboxylate;3-4-3=N,N'bis(3-aminopropyl)-1,4-diaminobutane), process modeling, scale up, and a techno-economic optimization of a moving bed Temperature Swing Adsorption (TSA) process for carbon capture using this sorbent. This MOF exhibits a unique two-step CO 2 adsorption profile in three different pressure ranges. Thus, arctangent-based logistic functions and, quadratic and Langmuir models were employed to represent such isotherm behavior. The results of the isotherm model show good fitting vs the experimental data with an RMSE of 0.41. Here, to model the carbon capture process, the isotherm model was embedded into a moving bed contactor model, and this was used to simulate a TSA CO 2 capture cycle and evaluate cost-optimal designs considering flue gas from a -650 MWe NGCC power plant. The capital cost model consists of CAPEX correlations for reactors, compressors, ducting, etc., while the operating costs include steam, water, chemicals, and electricity (following NETL's quality guidelines for energy systems studies). A techno-economic optimization of the capture system was performed by using NETL's Framework for the Optimization and Quantification of Uncertainty and Surrogates tool (FOQUS). Results suggest that a moving bed carbon capture system with tetraamine-appended MOF can be competitive compared to conventional MEA solvent-based capture processes for NGCC plants, when a heat recovery efficiency of at least 40% is achieved, and MOF materials can be produced at a cost below -$9/kg.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Quality appraisal of clinical practice guidelines for the management of Dysphagia after acute stroke

Objectives Dysphagia is a common complication in stroke patients, widely affecting recovery and quality of life after stroke. The objective of this systematic review is to identify the gaps that between evidence and practice by critically assessing the quality of clinical practice guidelines (CPGs) for management of dysphagia in stroke. Methods We systematically searched academic databases and guideline repositories between January 1, 2014, and August 1, 2023. The Appraisal of Guidelines for Research and Evaluation (AGREE II) instrument was used by two authors to independently assess CPG quality. Results In a total of 14 CPGs included, we identified that three CPGs obtained a final evaluation of “high quality,” nine CPGs achieved “moderate quality” and two CPGs received “low quality.” The domain of “scope and purpose” achieved the highest mean score (91.1%) and the highest median (IQR) of 91.7% (86.1, 94.4%), while the domain of “applicability” received the lowest mean score (55.8%) and the lowest median (IQR) of 55.4% (43.2, 75.5%). Conclusion The CPG development group should pay more attention to improving the methodological quality according to the AGREE II instrument, especially in the domain of “applicability” and “stakeholder involvement;” and each item should be refined as much as possible.

Gao, Shi-Lin↗

Diagnostic imaging of hepatocellular carcinoma at community hospitals and their tertiary referral center in the era of LI-RADS: a quality assessment study

Purpose: To assess guideline compliance and quality of hepatocellular carcinoma, (HCC) diagnostic imaging within community hospitals (CH) and their Tertiary referral center (TRC) in a moderately high incidence region. Methods: Initial diagnostic workup CT/MRI scans of 251 patients (122 CH, 112 TRC, 17 Non-TRC academic) with HCC over a 15-month period were assessed for Liver reporting and Data System (LI-RADS) guideline compliance. 269 scans (182 CT, 87 MRI) were qualitatively evaluated by 2 independent blinded radiologists for arterial timing, overall image quality, noise and sharpness, with quantification of interobserver variability. The contrast enhancement ratio (CER) for the largest HCC on each scan was calculated using pre- and post-contrast images. Results: 103/104 (99%) of TRC and 44/78 (56%) of CH CTs adhered to LI–RADS imaging guidelines (P < 0.0001). Lack of delayed phase accounted for 32/34 (94%) of noncompliant CH CTs. Regarding MRI, 19/19 (100%) of TRC and 60/68 (88%) of CH scans were adherent (P = 0.12). For both modalities, overall image quality, noise and sharpness were rated significantly higher for TRC than CH. There was moderate interobserver agreement with intraclass correlation coefficient of 0.73, 0.70 and 0.63, respectively. Arterial-phase timing was rated adequate for CT in 75/104 TRC (72%) and 10/68 (14%) CH scans (P < 0.0001) and for MRI in 8/19 (42%) TRC and 23/68 (33%) CH scans (P = 0.17). The CER was significantly higher for TRC versus CH (2.9 vs. 1.9, P < 0.001) and MRI (0.9 vs. 0.7, P = 0.03). Conclusions: Community hospital HCC diagnostic scans significantly lag in critical quality parameters of tumor enhancement, arterial phase timing, perceived image quality, and LI-RADS CT technique compliance compared to a TRC.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Photovoltaic System Health-State Architecture for Data-Driven Failure Detection

The timely detection of photovoltaic (PV) system failures is important for maintaining optimal performance and lifetime reliability. A main challenge remains the lack of a unified health-state architecture for the uninterrupted monitoring and predictive performance of PV systems. To this end, existing failure detection models are strongly dependent on the availability and quality of site-specific historic data. The scope of this work is to address these fundamental challenges by presenting a health-state architecture for advanced PV system monitoring. The proposed architecture comprises of a machine learning model for PV performance modeling and accurate failure diagnosis. The predictive model is optimally trained on low amounts of on-site data using minimal features and coupled to functional routines for data quality verification, whereas the classifier is trained under an enhanced supervised learning regime. The results demonstrated high accuracies for the implemented predictive model, exhibiting normalized root mean square errors lower than 3.40% even when trained with low data shares. The classification results provided evidence that fault conditions can be detected with a sensitivity of 83.91% for synthetic power-loss events (power reduction of 5%) and of 97.99% for field-emulated failures in the test-bench PV system. Finally, this work provides insights on how to construct an accurate PV system with predictive and classification models for the timely detection of faults and uninterrupted monitoring of PV systems, regardless of historic data availability and quality. Such guidelines and insights on the development of accurate health-state architectures for PV plants can have positive implications in operation and maintenance and monitoring strategies, thus improving the system’s performance.

photovoltaics↗

Simulation-based assessment of ASHRAE Guideline 36, considering energy performance, indoor air quality, and control stability

This study assesses American Society of Heating, Refrigerating and Air-Conditioning Engineers Guideline 36 (G36) with a typical medium office building. Specifically, this study employed a Modelica model of a variable air volume (VAV) system that serves this building, which includes components for representing indoor virus transmission and filtration. It then implemented the G36 control sequences for both water-side and air-side equipment in Python. After that, this study conducted the assessment by co-simulating G36 and the Modelica model using the Building Operations Testing Framework. Unlike existing works, this work has three unique features: (1) It considers the interactions between control sequences for water-side and air-side equipment of the studied VAV system. (2) It assesses the performance of G36 from the perspective of IAQ. (3) It examines the short-term behaviors of the studied building under G36 to understand the control stability. This assessment confirms significant energy savings from G36, largely because of the interaction between supply air temperature and hot water controls. It also reveals a trade-off between the ability to slow the spread of virus and the energy performance via demand controlled ventilation. Lastly, it emphasizes the necessity of tuning local feedback control when implementing G36.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗