Multistep Procedure Research Articles

Inverter Operation Mode of a PhotoVoltaic Cascaded H-Bridge Battery Charger

The paper deals with a grid-connected single-phase battery charger integrated with photovoltaic generators (PVGs). The circuit topology consists of a multilevel architecture based on a Cascaded H-Bridge (CHB) rectifier. Its main task is to charge the batteries, primarily from the PVGs, by also assuring to keep their state-of-charge (SOC) balanced. Nevertheless, when the battery SOC overcomes a predefined upper limit, beyond which the charging process could be interrupted, the available PV power can no longer be transferred to the batteries. Therefore, to avoid an undesired curtailment of PV power production, this latter can be supplied to the grid by inverting the system operation. The paper shows how to achieve this result by implementing a dedicated control action based on a multi-step procedure. Numerical investigations are carried out on a 19-level CHB converter implemented in the PLECS environment to validate the feasibility and effectiveness of the proposed control technique.

Print-Light-Synthesis for Single-Step Metal Nanoparticle Synthesis and Patterned Electrode Production.

The fabrication of thin-film electrodes, which contain metal nanoparticles and nanostructures for applications in electrochemical sensing as well as energy conversion and storage, is often based on multi-step procedures that include two main passages: (i) the synthesis and purification of nanomaterials and (ii) the fabrication of thin films by coating electrode supports with these nanomaterials. The patterning and miniaturization of thin film electrodes generally require masks or advanced patterning instrumentation. In recent years, various approaches have been presented to integrate the spatially resolved deposition of metal precursor solutions and the rapid conversion of the precursors into metal nanoparticles. To achieve the latter, high intensity light irradiation has, in particular, become suitable as it enables the photochemical, photocatalytical, and photothermal conversion of the precursors during or slightly after the precursor deposition. The conversion of the metal precursors directly on the target substrates can make the use of capping and stabilizing agents obsolete. This review focuses on hybrid platforms that comprise digital metal precursor ink printing and high intensity light irradiation for inducing metal precursor conversions into patterned metal and alloy nanoparticles. The combination of the two methods has recently been named Print-Light-Synthesis by a group of collaborators and is characterized by its sustainability in terms of low material consumption, low material waste, and reduced synthesis steps. It provides high control of precursor loading and light irradiation, both affecting and improving the fabrication of thin film electrodes.

Metal-Phenolic Film Coated Quartz Crystal Microbalance as a Selective Sensor for Methanol Detection in Alcoholic Beverages.

The facile real-time monitoring of methyl content in fermented beverages is of fundamental significance in the alcohol and restaurant industry, since as little as 4 mL of methanol entering the blood may cause intoxication or blindness. So far, the practical applicability of available methanol sensors, including the piezoresonance analogs, is somewhat limited to laboratory use due to the complexity and bulkiness of the measuring equipment involving multistep procedures. This article introduces a hydrophobic metal-phenolic film-coated quartz crystal microbalance (MPF-QCM) as a novel streamlined detector of methanol in alcoholic drinks. Unlike other QCM-based alcohol sensors, our device operates under saturated vapor pressure conditions, permitting rapid detection of methyl fractions up to seven times below the tolerable levels in spirits (e.g., whisky) while effectively suppressing the cross-sensitivity to interfering chemical compounds such as water, petroleum ether or ammonium hydroxide. Furthermore, the good surface adhesion of metal-phenolic complexes endows the MPF-QCM with superior long-term stability, contributing to the repeatable and reversible physical sorption of the target analytes. These features, combined with the lack of mass flow controllers, valves and connecting pipes delivering the gas mixture, outline the likelihood for future design of a portable MPF-QCM prototype suitable to point-of-use analysis in drinking establishments.

CRISPR/Cas13a-Based MicroRNA Detection in Tumor-Derived Extracellular Vesicles.

MicroRNAs (miRNAs) in extracellular vesicles (EVs) play essential roles in cancer initiation and progression. Quantitative measurements of EV miRNAs are critical for cancer diagnosis and longitudinal monitoring. Traditional PCR-based methods, however, require multi-step procedures and remain as bulk analysis. Here, the authors introduce an amplification-free and extraction-free EV miRNA detection method using a CRISPR/Cas13a sensing system. CRISPR/Cas13a sensing components are encapsulated in liposomes and delivered them into EVs through liposome-EV fusion. This allows for accurately quantify specific miRNA-positive EV counts using 1 × 108 EVs. The authors show that miR-21-5p-positive EV counts are in the range of 2%-10% in ovarian cancer EVs, which is significantly higher than the positive EV counts from the benign cells (<0.65%). The result show an excellent correlation between bulk analysis with the gold-standard method, RT-qPCR. The authors also demonstrate multiplexed protein-miRNA analysis in tumor-derived EVs by capturing EpCAM-positive EVs and quantifying miR-21-5p-positive ones in the subpopulation, which showsignificantly higher counts in the plasma of cancer patients than healthy controls. The developed EV miRNA sensing system provides the specific miRNA detection method in intact EVs without RNA extraction and opens up the possibility of multiplexed single EV analysis for protein and RNA markers.

Meta-heuristic aggregate calibration of transport models exploiting data collected in mobility

The wide diffusion of data collected in mobility led to an unprecedented amount of information about people's mobility behavior. While on one hand the availability of big data from multiple sources enables to calibrate complex models with a high number of parameters, on the other hand, the dimension of the problem increases, and computational efficiency becomes an important issue. The paper presents a general methodology for the aggregate calibration of transport system models that exploits data collected in mobility jointly with other data sources within a multi-step optimization procedure based on metaheuristic algorithms. The methodology is applied to two real large-scale case studies in two different contexts. The first concerns the aggregate calibration updating a national strategic 4-step demand model in use in a big European Country; the second deals with the calibration of link and node performance functions implemented in a traffic network model of a town of around 3 million inhabitants. The results demonstrate the effectiveness of the aggregate calibration methodology in significantly improving earlier models’ estimations. The results also highlight that the errors are in the same order of magnitude as the intrinsic variation of the data collected in the field.

Electrochemically Generated Carbanions Enable Isomerizing Allylation and Allenylation of Aldehydes with Alkenes and Alkynes.

The direct coupling of aldehydes with petrochemical feedstock alkenes and alkynes would represent a practical and streamlined approach for allylation and allenylation chemistry. However, conventional approaches commonly require preactivated substrates or strong bases to generate allylic or propargylic carbanions and only afford branched allylation or propargylation products. Developing a mild and selective approach to access synthetically useful linear allylation and allenylation products is highly desirable, albeit with formidable challenges. We report a strategy using hydrogen evolution reaction (HER) to generate a carbanion from weakly acidic sp3 C-H bonds (pKa ∼ 35-40) under mild reaction conditions, obviating the use of strong bases, Schlenk techniques, and multistep procedures. The cathodically generated carbanion reverses the typical reaction selectivity to afford unconventional isomerizing allylation and allenylation products (125 examples). The generation of carbanions was monitored and identified by in situ ultraviolet-visible (UV-vis) spectroelectrochemistry. Furthermore, we extended this protocol to the generation of other carbanions and their application in coupling reactions between alcohols with carbanions. The appealing features of this approach include mild reaction conditions, excellent functional group tolerance, unconventional chemo- and regioselectivity, and the diverse utility of products, which includes offering direct access to diene luminophores and bioactive scaffolds. We also performed cyclic voltammetry, control experiments, and density functional theory (DFT) calculations to rationalize the observed reaction selectivity and mechanism.

Development of fast dissolving polymer-based microneedles for delivery of an antigenic melanoma cell membrane

Delivery of cancer cell membranes (CM) is a new approach for the activation of the immune system and the induction of immunotherapy of cancer. Local delivery of melanoma CM into skin can induce efficient immune stimulation of antigen presenting cells (APCs), such as dendritic cells. In the current study, fast dissolving microneedles (MNs) were developed for the delivery of melanoma B16F10 CM. Two polymers were tested for the fabrication of MNs: poly(methyl vinyl ether-co-maleic acid) (PMVE-MA) and hyaluronic acid (HA). The incorporation of CM in MNs was achieved through coating of the MNs using a multi-step layering procedure or the micromolding technique. The CM loading and its stabilization were improved by adding sugars (sucrose and trehalose) and a surfactant (Poloxamer 188), respectively. In an ex vivo experiment, both PMVE-MA and HA showed fast dissolutions (<30 s) after insertion into porcine skin. However, HA-MN showed better mechanical properties, namely improved resistance to fracture when submitted to a compression force. Overall, a B16F10 melanoma CM-dissolving MN system was efficiently developed as a promising device suggesting further studies in immunotherapy and melanoma applications.

A low-concentration 2-step synthesized spiroquaternary ammonium salt electrolyte for commercially stable pouch-type supercapacitors

Currently, non-aqueous, stable supercapacitors manufactured for commercial use require an environmentally benign and economically viable electrolyte synthesis technique. Spiro-based salts dissolved in organic solvents are known to have smaller ion-size, which facilitate charge transport during storage at varying temperatures and preserve storage efficiency over time. Previously, the synthesis of spirobased salt syntheses via complex multistep procedures involving toxic chemical solvents and low yields have been reported. The current work proposes a modified water-based ion-exchange process coupled with an innovative purification step that results in improved yield. In addition, the synthesized spiro-(1,1′)-bipyrrolidinium tetrafluoroborate (SBPBF4) salt mixed in an optimized organic solvent blend produced a dilute (0.2 M) electrolyte with its ionic conductivity comparable to commercially recognized, higher concentrated ionic salt electrolytes (3 M). Using the dilute SBPBF4 electrolyte, the pouch-type (PoC-SBF4) devices were operated up to 3 V.An average rated capacitance of 300 F was demonstrated with up to 43 W h kg−1 specific energy and 1 kW kg−1 of maximum deliverable power. After 10,000 continuous charge-discharge cycles, the device retained 97 % of its capacitance at an applied current of 5 A.Notably, the extreme temperature shock tests at −70 °C also demonstrated ~60 % capacitance retention after subjecting the device to cycling at 5 A for 72 h (3 days) to simulate extreme weather conditions for potential integration with renewable energy, mobility, or deep space applications.The water-based ion exchange step and the use of dilute electrolytes reduces the overall cost of manufacturing supercapacitor when scaling up the production process. The results presented provides a critical evaluation of the criteria for developing robust, stable, and low-cost supercapacitors from laboratory to large-scale manufacturing.

Accelerating Non-Empirical Structure Determination of Ziegler–Natta Catalysts with a High-Dimensional Neural Network Potential

The determination of catalyst nanostructures with first-principles accuracy using genetic algorithms (GA) is very demanding due to the cubic scaling of the computational cost of density functional theory (DFT) calculations. Here, we demonstrate, for the case of Ziegler–Natta MgCl2/TiCl4 nanoplates, how this structure determination can be accelerated by employing a high-dimensional neural network potential (HDNNP) of essentially DFT accuracy. First, when building HDNNPs for MgCl2/TiCl4 clusters with computationally tractable sizes, we found that the structural diversity in the training set is crucial for obtaining HDNNPs reliably describing the large variety of structures generated by GA. The resulting HDNNPs dramatically accelerated the structure determination while yielding results consistent with DFT. Subsequently, we developed a multistep adaptive procedure to construct a HDNNP for MgCl2/TiCl4 clusters consistent in size and TiCl4 coverage with experiments where prior DFT results were scarcely collected. The structure determination and analyses underline the importance of system size and composition in order to predict some experimentally known facts such as the surface morphology and population of isospecific sites.

The role of stakeholder involvement in the evolving EU HTA process: Insights generated through the European Access Academy’s multi-stakeholder pre-convention questionnaire

ABSTRACT Involvement of all relevant stakeholders will be of utmost importance for the success of the developing EU HTA harmonization process. A multi-step procedure was applied to develop a survey across stakeholders/collaborators within the EU HTA framework to assess their current level of involvement, determine their suggested future role, identify challenges to contribution, and highlight efficient ways to fulfilling their role. The ‘key’ stakeholder groups identified and covered by this research included: patients‘, clinicians‘, regulatory, and Health Technology Developer representatives. The survey was circulated to a wide expert audience including all relevant stakeholder groups in order to determine self-perception by the ‘key’ stakeholders regarding involvement in the HTA process (self-rating), and in a second, slightly modified version of the questionnaire, to determine the perception of ‘key’ stakeholder involvement by HTA bodies, payers, and policymakers (external rating). Predefined analyses were conducted on the submitted responses. Fifty-four responses were received (patients9; clinicians: 8; regulators: 4; HTDs 14; HTA bodies: 7; Payers: 5; policymakers 3; others 4). The mean self-perceived involvement score was consistently lower for each of the ‘key’ stakeholder groups than the respective external ratings. Based on the qualitative insights generated in the survey, a RACI Chart (Responsible/Accountable/Consulted/Informed) was developed for each of the stakeholder groups to determine their roles and involvement in the current EU HTA process. Our findings suggest extensive effort and a distinct research agenda are required to ensure adequate involvement of the key stakeholder groups in the evolving EU HTA process.

Emotional (in)stability: Neuroticism is associated with increased variability in negative emotion after all

The personality trait neuroticism is tightly linked to mental health, and neurotic people experience stronger negative emotions in everyday life. But, do their negative emotions also show greater fluctuation? This commonsensical notion was recently questioned by [Kalokerinos et al. Proc Natl Acad Sci USA 112, 15838-15843 (2020)], who suggested that the associations found in previous studies were spurious. Less neurotic people often report very low levels of negative emotion, which is usually measured with bounded rating scales. Therefore, they often pick the lowest possible response option, which severely constrains the amount of emotional variability that can be observed in principle. Applying a multistep statistical procedure that is supposed to correct for this dependency, [Kalokerinos et al. Proc Natl Acad Sci USA 112, 15838-15843 (2020)] no longer found an association between neuroticism and emotional variability. However, like other common approaches for controlling for undesirable effects due to bounded scales, this method is opaque with respect to the assumed mechanism of data generation and might not result in a successful correction. We thus suggest an alternative approach that a) takes into account that emotional states outside of the scale bounds can occur and b) models associations between neuroticism and both the mean and variability of emotion in a single step with the help of Bayesian censored location-scale models. Simulations supported this model over alternative approaches. We analyzed 13 longitudinal datasets (2,518 individuals and 11,170 measurements in total) and found clear evidence that more neurotic people experience greater variability in negative emotion.

Supramolecular nanoassemblies-mediated GSH depletion boosts synergistic chemo- and photodynamic therapy for immunogenicity enhancement

O2-dependent photodynamic therapy (PDT) generally suffers from compromised therapeutic efficiency due to a hypoxic tumor microenvironment. The therapeutic efficiency enhancement of PDT in a hypoxic tumor microenvironment usually requires sophisticated chemical design and multistep preparation and purification procedures. The development of a facile yet robust strategy to improve the therapeutic efficiency of PDT is thus highly desirable for clinical translations, but remains a significant challenge. For this purpose, we reported herein the use of Azobenzene (Azo) not only as conjugation sites for facile construction of multicomponent supramolecular nanomedicine based on a guest homopolymer poly(Azobenzene) (PAzo) and three β-CD-decorated host moieties, i.e., β-CD-modified photosensitizer chlorin e6 (β-CD-Ce6), chemotherapeutic drug cisplatin (β-CD-Pt(IV)), and hydrophilic poly(oligo ethylene glycol) methacrylate (β-CD-POEGMA) via host–guest interactions, but also for glutathione (GSH) depletion-enhanced synergistic chemo- and photodynamic therapy via hypoxia-triggered cleavage of Azo. Notably, the resulting self-assembled supramolecular nanoparticles (NPs) with a Ce6, platinum(IV), and POEGMA molar ratio of 8:8:2 (NPCe6/Pt) mediated greater cytotoxicity with a half maximal inhibitory concentration (IC50) value 6-fold lower than that of free Ce6 under a hypoxia condition with 660 nm laser irradiation because Azo cleavage-induced GSH depletion boosts synergistic chemo- and photodynamic therapy, which further led to immunogenicity enhancement with a tumor inhibition rate of 93.1 % in a murine 4T1 transplantation tumor model. The modularized supramolecular nanoplatform developed herein provides a facile yet robust strategy for advanced combinatory cancer therapy with great potential for clinical translations.

A simple and accurate LC‑MS/MS method for monitoring cyclosporinA that is suitable for high throughput analysis.

With time, the number of samples in clinical laboratories from therapeutic drug monitoring has increased. Existing analytical methods for blood cyclosporin A (CSA) monitoring, such as high-performance liquid chromatography (HPLC) and immunoassays, have limitations including cross-reactivity, time consumption, and the complicated procedures involved. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) has long been considered the reference standard owing to its high accuracy, specificity, and sensitivity. However, large numbers of blood samples, multi-step preparation procedures, and longer analytical times (2.5-20 min) are required as a consequence of the different technical strategies, to ensure good analytical performance and routine quality assurance. A stable, reliable, and high throughput detection method will save personnel time and reduce laboratory costs. Therefore, a high throughput and simple LC-MS/MS method was developed and validated for the detection of whole-blood CSA with CSA-d12 as the internal standard in the present study. Whole blood samples were prepared through a modified one-step protein precipitation method. A C18 column (50x2.1 mm, 2.7 µm) with a mobile phase flow rate of 0.5 ml/min was used for chromatographic separation with a total running time of 4.3 min to avoid the matrix effect. To protect the mass spectrometer, only part of the sample after LC separation was allowed to enter the mass spectrum, using two HPLC systems coupled to one mass spectrometry. In this way, throughput was improved with detection of two samples possible within 4.3 min using a shorter analytical time for each sample of 2.15 min. This modified LC-MS/MS method showed excellent analytical performance and demonstrated less matrix effect and a wide linear range. The design of multi-LC systems coupled with one mass spectrometry may play a notable role in the improvement of daily detection throughput, speeding up LC-MS/MS, and allowing it to be an integral part of continuous diagnostics in the near future.

Towards a framework for light-dosimetry studies: Quantification metrics

Light dosimetry aims to measure personal light exposure with wearable sensors, which is a complex multistep procedure. The resulting data may be used to investigate non-visual effects of light in real-life settings, to validate laboratory findings and answer questions pertaining to implications in applied contexts. However, personal light exposure patterns are usually complex and can be quantified in many ways. Various measurement and analysis methods have been applied across previous studies, complicating comparability and interpretation of results. To improve the quality and comparability of light-dosimetry research, a framework with consensus guidelines for light-dosimetry procedures is needed. To provide the groundwork towards such a framework, we reviewed previous light-dosimetry studies to identify considerations regarding measurement and data quantification. Here, we review metrics for quantifying light-dosimetry data in terms of the characteristics known to modulate non-visual responses. Overall, various metrics have been employed across studies, with several metrics for each characteristic. We provide a description of each metric, discuss their properties and provide example calculations for the application to light-dosimetry data. Moreover, we propose considerations for data quantification and possible research strategies for future studies. To facilitate exploration and use of the identified metrics, corresponding functions are provided in an openly accessible R-package.

Two-Temperature Modeling of Nonequilibrium Relaxation and Dissociation in Shock-Heated Oxygen

Two-temperature models for coupled vibrational relaxation and dissociation in shock-heated oxygen are assessed using low-uncertainty measured data from reflected shock tube experiments. A computationally efficient multistep technique is developed to model the unsteady dynamics of shock reflection in a relaxing and dissociating gas. The developed technique is then benchmarked through comparison with unsteady computational fluid dynamic simulations. Results from the benchmarking effort demonstrate that the adopted multistep modeling procedure accurately captures the dominant gas dynamic effects influencing the state of the test gas at the measurement location. A parametric study is then performed to assess several combinations of possible two-temperature modeling approaches for nonequilibrium oxygen dissociation. The current assessment demonstrates that the widely adopted Park model is inconsistent with the measured data, while the recently developed modified Marrone and Treanor (MMT) model demonstrates promising agreement with the data. The results of the present study clearly indicate that the MMT model is more appropriate for two-temperature modeling of nonequilibrium oxygen dissociation than the legacy Park model. Patterns in the parametric comparison also suggest that the approximate treatment of non-Boltzmann vibrational state distributions within the MMT model may require improvement.

Hocance tourism motivations: Scale development and validation

Hocance is a compound word of ‘hotel’ and ‘vacance’. This concept is created from the established and popular trending culture of spending vacations in hotels. We applied a rigorous multi-step scale development procedure to craft a scale that measures Hocance tourism motivations (HTM). Using grounded theory, we conducted interviews with individuals with Hocance experience in South Korea to develop a conceptual model involving seven dimensions: pragmatism, pleasure, curiosity, respite, ostentation, impregnability, and amotivation. We tested the proposed scale using data obtained from surveys with 1,000 tourists. To validate the scale, we conducted a further survey (n = 199) with paid membership subscribers of two luxury hotels in Seoul. The survey results confirmed the reliability and validity of five dimensions of HTM namely, pragmatism, curiosity, respite, ostentation, and impregnability. We discussed theoretical and managerial implications and directions for future research for the newly developed scale of HTM.

Films enriched with semiconducting single-walled carbon nanotubes by aerosol N2O etching

Semiconducting single-walled carbon nanotubes (SWCNTs) are of particular interest to electronics. As most of synthesis methods yield 1/3 of metallic SWCNTs, the route for a purely semiconducting species is a complex multistep procedure. Herein, we report a simple one-step method for selective etching of metallic SWCNTs in the aerosol phase with nitrous oxide. Our approach is based on a tandem of two flow reactors, where the first one is needed to produce individual SWCNTs, and the second one is to eliminate metallic SWCNTs due to their faster oxidization rate. The oxidant (N2O) adsorption on the SWCNT surface was modelled by DFTB taking into account geometric characteristics of the nanotube and its electronic properties, resulting in less N2O adsorption energy for metallic SWCNTs of some chiralities than for semiconducting ones. Thus, we obtained SWCNT films enriched with semiconducting nanotubes up to optical selectivity of 97% by treatment of pristine SWCNT aerosols for 6 s at 600 °C in an atmosphere of 30% N2O. The treated films show a turnaround of the temperature dependence of the resistance. As a proof of the concept, enriched SWCNT films were utilized as a channel material for thin film field effect transistors, which show an average improvement of ON/OFF current ratio from 1- 10 to 10 - 104 for the same open state resistance for the statistical sampling based on more than 7500 devices.

Membrane-based microfluidic solvent extraction of Ga-68 from aqueous Zn solutions: towards an automated cyclotron production loop

BackgroundThe radionuclide Ga-68 is commonly used in nuclear medicine, specifically in positron emission tomography (PET). Recently, the interest in producing Ga-68 by cyclotron irradiation of [68Zn]Zn nitrate liquid targets is increasing. However, current purification methods of Ga-68 from the target solution consist of multi-step procedures, thus, leading to a significant loss of activity through natural decay. Additionally, several processing steps are needed to recycle the costly, enriched target material.ResultsTo eventually allow switching from batch to continuous production, conventional batch extraction and membrane-based microfluidic extraction were compared. In both approaches, Ga-68 was extracted using N-benzoyl-N-phenylhydroxylamine in chloroform as the organic extracting phase. Extraction efficiencies of up to 99.5% ± 0.6% were achieved within 10 min, using the batch approach. Back-extraction of Ga-68 into 2 M HCl was accomplished within 1 min with efficiencies of up to 94.5% ± 0.6%. Membrane-based microfluidic extraction achieved 99.2% ± 0.3% extraction efficiency and 95.8% ± 0.8% back-extraction efficiency into 6 M HCl. When executed on a solution irradiated with a 13 MeV cyclotron at TRIUMF, Canada, comparable efficiencies of 97.0% ± 0.4% were achieved. Zn contamination in the back-extracted Ga-68 solution was found to be below 3 ppm.ConclusionsMicrofluidic solvent extraction is a promising method in the production of Ga-68 achieving high efficiencies in a short amount of time, potentially allowing for direct target recycling.Graphical

Creating Implicit Measure Stimulus Sets Using a Multi-Step Piloting Method.

The effect of arbitrary stimulus selection is a persistent concern when employing implicit measures. The current study tests a data-driven multi-step procedure to create stimulus items using a combination of free-recall and survey data. Six sets of stimulus items were created, representing healthy food and high sugar items in children, adolescents, and adults. Selected items were highly representative of the target concepts, in frequent use, and of near equal length. Tests of the piloted items in two samples showed slightly higher implicit measure-behavior relations compared to a previously used measure, providing preliminary support for the value in empirically based stimulus selection. Further, the items reported as being the most associated with their target concepts differed notably from what one may expect from the guidelines or population consumption patterns, highlighting the importance of informed stimulus selection.

Perspectives of photovoltaic energy market development in the european union

Photovoltaic (PV) energy has recently been gaining much attention worldwide. It is the least expensive energy source which can be used to replace part of the energy from fossil fuels. The European Union (EU) published the European Green Deal in 2019 with the aim of achieving climate neutrality. The PV solar energy market has gained technological maturity and can help to achieve these climate targets. This article provides an analysis of PV energy usage in the EU by comparing the consumption of PV energy in EU countries. The study is important because there has been a shift from fossil fuels to renewable energy sources. The PV energy is getting more interest worldwide as a source of clean and cheap energy. The data were then analyzed for the world, the EU, and the USA. The main sources of information were the Statistical Office of the European Communities (EUROSTAT) data and International Renewable Energy Agency (IRENA) data. Extended methods were used to check the processes in PVs and a multi-step procedure was conducted. The first step was to check the stationarity of the process by using the Augmented Dickey-Fuller test (ADF test), which involved testing two hypotheses. The first hypothesis was that the process of PV capacity is stationary, and the second hypothesis was that the time series process is not stationary. In the second step, descriptive statistics were used to analyze the changes in PV consumption in EU countries. In the third step, an Autoregressive Integrated Moving Average (ARIMA) model was created in which one-dimensional autoregression models and a moving average for forecasting were calculated for each EU country. Finally, the procedure was supplemented with additional information for a prognosis. This research demonstrated a huge increase in the development of PVs in EU countries. All countries of the EU increased their PV capacity from 2000 to 20. The largest PV producers are Germany, Italy, and Spain, and the smallest are Latvia, Bulgaria, and Lithuania. The key policy implications are as follows: the European Union (EU) should finance the changes in the energy sector to a greater extent. Moreover, the PV development in the EU will be dependent on the climate and energy policies. The development of PV will depend on the actions of not only the EU but also global markets players such as China and the USA.