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Battery energy storage systems (BESS) have started to be part of the photovoltaic (PV) system design to allow the further penetration of PV into the grid. This study deals with the sizing (power and energy capacity) of a BESS for residential households which are represented by a typical load consumption profile, they have electrical air conditioning and electrical water heating (water boiler) resembling a common residential house in Cyprus. The BESS sizing is done considering the local energy consumption profile and the energy efficiency class of the house and the water boiler. The BESS is sized in order to achieve zero PV grid export and to increase self-consumption. 2019 18 4770 4774

We developed anin silicoapproach to model B16F10 melanoma cell response to a helium atmospheric pressure plasma jet (APPJ) or/and doxorubicin drug (DOX). Thein silicomodel is informed by relevant data from previously publishedin vitroexperiments (cancer cell viability), providing detailed information on (i) cell population number (Ncell) development during incubation and (ii) probability values for apoptosis (%PApoptosis) and mitosis (%PMitosis) following cell subjection to the plasma-conditioned RPMI-1640 medium (PC-RPMI), DOX, and DOX combined with APPJ. When treating cancer cells with PC-RPMI and DOX separately, at the smallest plasma duration (dPlasma = 15 s) and DOX concentration (cDOX = 0.05 μM), only a small decline in Ncell, an increase in %PApoptosis, or/and a decrease in %PMitosisare measured with respect to the control conditions (non-treated cancer cells). However, cell cytotoxicity is increasingly enhanced with increasingdPlasmaandcDOXup to 120 s and 0.5 μM, respectively. At those highest values studied inin silico, simulated %PApoptosisare significantly larger than %PMitosis, resulting in a severe decrease in Ncellcompared to control in agreement with the correspondingin vitroexperiments.&nbsp

Dielectric barrier discharges are one of the most common plasma-based ion sources in mass spectrometry. The versatility in design and the ability to miniaturize the ion sources in addition to the observed performance have made them popular. Low-temperature plasma (LTP), dielectric barrier discharge ionization (DBDI), or flexible microtube plasma (FµTP) are three examples of high-frequency alternative current operated plasmas. The different designs should involve different energies to the ions during the gas-phase ionization. As shown in the literature, Thermometer ions are the favorite molecules to study the internal energy deposited on the ions during positive ion mode ionization. Here, we proposed the investigation of different DBDI ion sources designs internal energy distributions evaluation.

Electroporation is used in electrochemotherapy, gene therapy, DNA transfer etc. Electroporation is typically achieved through conductive wires. In this abstract we describe an alternative and non-contact method of achieving electroporation, i.e. through the use of atmospheric pressure plasma jets (APPJs). In a recent study of Helium APPJ it was found that the addition of oxygen admixtures increased its effectiveness in cancer treatment. This effectiveness was attributed to reactive oxygen and nitrogen species (RONS) produced by the APPJ. However, a recent simulation study from our team showed that the oxygen admixtures increase the strength of the induced electric field (IEF) on the treated surface. We propose that this IEF increases the cell membrane permeability, and thus helps molecules penetrate into the cells. So, it can be inferred that the effectiveness of APPJs lies in the combination of the two effects (high amount of RONS and high IEFs on the treated surface)., Poster presentation at the 8th international conference on plasma medicine, August 2021, Icheon South Korea held online

During the past decade, computer modeling of atmospheric pressure plasma jets (APPJs) has attracted scientific attention. Particularly, several plasma fluid models (PFM) have been developed, involving commercially-available software or in-house codes, which have provided significant insight of plasma propagation mechanisms, production pathways of reactive oxygen and nitrogen species (RONS), electric field dynamics, and plasma interaction with solid/liquid targets. Combining computer models with targeted experiments, invaluable information can be obtained for the optimization of APPJs and their implementation in plasma medicine and cancer therapy. Therefore, modeling the effect of APPJs on solid tumors may offer promise in designing novel synergistic therapies (e.g., plasma with nanomedicine). The present study proposes a novel multiphysics/multiscale modeling approach that combines a PFM using COMSOL Multiphysics® and a cutting-edge in-silico framework for cancer modelling, FEB3., Oral presentation at the 8th international conference on plasma medicine, August 2021, Icheon South Korea held online

In this study, a two-dimensional axi-symmetric model has been developed in order to shed light into the evolution of a He and He/O2 capillary plasma jet. The plasma jet interacts with a dielectric surface placed normal to the jet axis to bring the model closer to applications. This work examines, from first principles, the shape and speed of the of the plasma bullet, the intensity of the induced electric (IEF) field on the dielectric surface and the underlying dominant chemical reactions of the plasma. Furthermore, the work provides insight and understanding into the mechanisms behind many experimental observations such as the torus (or donut) and sphere plasma bullet shapes for pure Helium and He/O2 plasma, respectively.

This work investigates the electroporation ability of plasma jets on healthy and cancerous tissue.

Helium DBDs at atmospheric pressure have shown very promising results in many biomedical applications, such as wound healing, treatment of cancer cells, bacterial inactivation etc. In such discharges the presence of water impurities is unavoidable and should be taken into consideration as they affect the plasma composition and plasma dynamics. Water impurities originate from humidity in the ambient air and from the plasma interaction with living tissue typically residing in moist environment. Consequently, understanding the effect of the water admixtures on helium/air discharges is a prerequisite for the utilization of these devices

For the experiments, 4.0 kV, 50 μs duration, 10 kHz pulses are used to excite the plasma discharge through a 20 cm long capillary soda lime glass tube with internal diameter of 0.9 mm. In order to capture the dynamic behaviour of the plasma jet, an Intensified Charged Coupled Device (ICCD) is used. For the simulation model, the gas mixing of the helium with the ambient air is treated through a gas dynamic model that feeds its output to the plasma fluid model [6]. The simulations focus on the effects of the presence of the dielectric target and that of the oxygen admixtures (500ppm-2000ppm) on the plasma bullet shape and speed, the induced electric field, the secondary emission flux of electrons and the dynamic behavior of the chemical reactions (separating also the Penning reaction contributions) responsible for the plasma jet propagation. The numerical and experimental results have good agreement and show that the evolution of the helium plasma jet is highly affected by the introduction of oxygen admixtures.

Atmospheric pressure plasma jets (APPJ) show great potential for biomedical applications. One of the most interesting applications is cancer treatment where APPJ was used effectively in a wide number of different scenarios and in some cases it even exhibited selectivity in treating cancer while leaving the healthy tissue intact. One of the newest developments is plasma enhanced chemotherapy (PEC) where CAP is used synergistically with chemotherapy. PEC promises not only to make chemotherapy more effective (achieving the same results with lower drug doses) but also to enable therapy on resistant cancers. Being able to reduce the drug does and still offer an effective treatment can have significant implications on the patient by limiting the harmful side effects of chemotherapy. In addition, PEC can allow for the treatment of previously untreated cancer.

In this study, a two-dimensional axi-symmetric model has been developed in order to shed light into the evolution of a He and He/O2 capillary plasma jet. The plasma jet interacts with a dielectric surface placed normal to the jet axis to bring the model closer to applications. This work examines, from first principles, the shape and speed of the of the plasma bullet, the intensity of the induced electric (IEF) field on the dielectric surface and the underlying dominant chemical reactions of the plasma. Furthermore, the work provides insight and understanding into the mechanisms behind many experimental observations such as the torus (or donut) and sphere plasma bullet shapes for pure Helium and He/O2 plasma, respectively., International Conference on Phenomena in Ionized Gases (XXXIV ICPIG), July 2019, Sapporo, Japan

In this study, a one-dimensional plasma fluid model is used to shed light into the evolution of a He/dry air (500 ppm, 79% N2 and 21% O2) dielectric barrier discharge (DBD) under different levels of water admixtures (20 to 2000 ppm). The model considers the analytical chemistry between helium, nitrogen, oxygen and water species and it is verified with experimental results to ensure its correctness. The simulation results show that water admixtures highly affect the discharge characteristics and the dominant ions in the mixture. In particular, it was observed that the increase of water in the mixture up to 600 ppm causes the reduction of the breakdown voltage, while above 600 ppm the breakdown voltage increases. Furthermore, the simulation results show that the most important positive ion in the mixture is H2O+ for 20 - 100 ppm of water admixtures and H11O5+ for 100 - 2000 ppm of admixtures. The most abundant negative charged species is found to be electrons for the range of water admixtures considered in this study. To interpret these results and to get an insight into the discharge evolution the main reaction pathways of ion production are investigated and analyzed.

Atmospheric pressure plasma jet (APPJ) can be generated in capillary tubes flowing with pure helium and with admixtures of oxygen into the pure helium. The jet exiting the tube can be used for a variety of applications through surface interaction. In this study, a twodimensional axi-symmetric model has been developed to provide insight into the evolution of capillary helium plasma jet with and without the presence of oxygen admixtures and its interaction with a dielectric surface placed normal to the jet axis. The model considers the gas mixing of helium and ambient air and the analytical chemistry between helium, nitrogen and oxygen species. Experiments were performed in similar conditions as the simulations in order to get qualitative agreement between them. The numerical and experimental results show that the evolution of the helium plasma jet is highly affected by the introduction of oxygen admixtures. In particular, it was observed that the addition of oxygen admixtures in the helium gas promotes plasma bullet propagation on the axis of symmetry of the tube (instead off axis propagation for the pure helium plasma jet). On the other hand, the presence of the dielectric surface (the slab placed in front of the tube exit) forces the plasma bullet to spread radially. Furthermore, the plasma bullet speed decreases when the helium plasma jet is operated in the presence of oxygen admixtures. The numerical results also showed that He/O2 plasma jets induced much higher electric fields on the dielectric surface in comparison to the pure helium plasma jet

In the last two decades, atmospheric pressure plasma jet (APPJ) has gained a lot of attention, due to its low production cost and the wide range of applications that it can be used for such as, plasma medicine, local surface modification, local sterilization etc. In particular, helium APPJ shows very promising results in selectively treating cancerous tissue while leaving the healthy tissue intact. However, the mechanism behind this is not very clear yet and is mainly attributed to the production of radicals which collide with the living tissue and the high electric field generated in the intracellular region. In this study, the transmembrane voltage (TMV) and therefore the ability for electroporation of healthy and diseased cells in the presence of the electric field induced by a helium APPJ is investigated via numerical simulations. Differences in the TMV could explain the ability of APPJ to selectively treat cancerous tissue.

Reactive oxygen and nitrogen species (RONS) play a central role in the immune system and on disease progression and therefore are important in the therapeutic abilities of the atmospheric pressure plasma jet (APPJ). In addition to RONS, the APPJ induces an electric field (IEF) on the biological cells. It can be inferred that it is the combination of IEF and RONS and not just RONS that gives the APPJ its unique therapeutic abilities, such as selectively treating cancer. In the case of helium APPJ it was found that the addition of oxygen impurities allowed for more effective treatment of cancer cells. Putting it all together, the hypothesis is that the addition of oxygen causes higher IEF on cancerous cells causing electroporation and the introduction of RONS in the cells causing apoptosis

The main aim of this paper is to numerically investigate the evolution of the different species in a capillary helium plasma jet, during the plasma bullet propagation. This study is performed in a wide range of air concentrations in the helium jet core (up to 16000 ppm). The simulation results showed that the helium species are only produced and propagated in the helium jet core (axisymmetric line of the tube). On the other hand, the nitrogen and oxygen species (for up to 7000 ppm air in the jet core) were produced and propagated at the side of the jet core. For level of air concentration (in the jet core) higher than 7000 ppm, the production and propagation of the nitrogen and oxygen species converges towards the helium jet core. In order to interpret the results, the mean reaction pathways behind the production of each species are examined. This analysis gives insight into the physics behind the evolution and characteristics of the plasma jet.

Low temperature atmospheric pressure plasma sources have received much attention in the last decades, due to low production cost, easy implementation and applications ranging from surface modification, sterilization, plasma medicine etc. Such plasma sources usually operate with inert gases such as argon, neon or helium, and their electrodes are covered with dielectric layers in order to avoid the transition to arcing. The inert gases are preferred because they create the conditions for lower power requirements and they can produce a wide range of reactive species. However, in several applications, extra admixtures of nitrogen or oxygen species are added in the gases, in order to enhance the production of the reactive species. In the literature, there is a very limited number of studies regarding the effect of these admixtures on the evolution of helium discharge over a wide range. Consequently, understanding the effect of these admixtures (nitrogen and oxygen) on the discharge evolution is very crucial for the utilization of helium atmospheric pressure plasma devices.

In the last two decades, the atmospheric pressure plasma jet has gained much attention, due to its low production cost and the wide range of applications such as plasma medicine, local surface modification, local sterilization etc. The plasma jet device has been extensively studied and significant understanding has been gained through analytical/simulation models and experiments. However, deep understanding of the detailed mechanisms of plasma jet evolution and its interaction with material surfaces needs further research. A two dimensional axisymmetric plasma fluid model was used, in order to study the evolution and interaction of a capillary helium plasma jet with a dielectric surface (glass, εr=8). The results of the simulation have been verified with experimental results.

Microgrids (μG) are an emerging and promising concept for the integration of distributed Renewable Energy Sources (RES) into the power grid by introducing local coordination of controllable distributed energy sources. The University of Cyprus (UCY) plans to evolve the whole campus into a μG with a 10 MWp PV and respective Battery Energy Storage System (BESS). The campus is ideal for a μG because it is connected to the national grid through only one Point of Common Coupling (PCC). The μG will target, among others, the reduction of the UCY electricity bill (e.g. by improved time of use and self-consumption) and will provide ancillary services such as voltage regulation at the PCC. This paper presents an analysis on optimizing the required PV power and BESS size (power and energy), control and technology based on the University’s load profile and the solar insolation in Cyprus. Furthermore, the cost of the proposed solution and operational reliability / flexibility of the system are compared for a centralized (single BESS for the whole campus) and distributed (one BESS per faculty building) storage solution. The imported and exported energy from/to the grid is priced based on the net-metering scheme that is currently in place in Cyprus. In addition to the flat net-metering tariff, the energy management system will utilize a simulated time of use tariff (Peak, Off-Peak, Intermediate) aiming to achieve peak shaving during peak hours by the use of PV and stored energy from off-peak hours. It is planned to analyse and determine the optimum BESS size and technology based on the tariff scheme, load and battery capital cost. It is therefore imperative that the optimum size and technology of the BESS is obtained in order to avoid a long payback period and to meet the UCY campus requirements

Workshop fto strengthen the Cypriot PV industry. Topics included technology,financing and funding opportunities.

In recent years, the atmospheric pressure plasma jet has gained a lot of attention due to its low production costs and therapeutic effects. These effects are mainly attributed to the production of radicals which collide with the living tissue and the high electric field generated in the intracellular region. Furthermore, it has been widely reported that plasma energy interacts differently with healthy and cancerous tissue. To elucidate this phenomenon the direct contact of helium plasma jet with living tissues (healthy skin and skin affected by cancer) and the resulting intracellular electric field were studied by using numerical modelling. A two-dimensional axisymmetric model was built for the analytical description of the helium plasma jet at atmospheric pressure, taking into account the present of dry air impurities

With the existing energy systems and electricity grids worldwide being developed as smart systems and grids with increased renewable energy in general, there are critical needs in smart grid knowledge, development, testing, demonstration, evaluation, education and training. The University of Cyprus (UCY) is presently establishing a complete new green-field campus in Nicosia and is looking at the opportunity to introduce smart, sustainable and cost and energy efficient solutions for the energy services at the campus as a truly smart grid living lab. As part of this vision, UCY plans to install 10MWp PV capacity and 1MW/1MWh battery storage at the campus. This paper presents the specific context of the power system in Cyprus and the future UCY microgrid along with the possible and expected impacts of the PV plant and Battery Energy Storage System. The battery control strategies are tested at the experimental facility SYSLAB at The Technical University of Denmark (DTU).; With the existing energy systems and electricity grids worldwide being developed as smart systems and grids with increased renewable energy in general, there are critical needs in smart grid knowledge, development, testing, demonstration, evaluation, education and training. The University of Cyprus (UCY) is presently establishing a complete new green-field campus in Nicosia and is looking at the opportunity to introduce smart, sustainable and cost and energy efficient solutions for the energy services at the campus as a truly smart grid living lab. As part of this vision, UCY plans to install 10MWp PV capacity and 1MW/1MWh battery storage at the campus. This paper presents the specific context of the power system in Cyprus and the future UCY microgrid along with the possible and expected impacts of the PV plant and Battery Energy Storage System. The battery control strategies are tested at the experimental facility SYSLAB at The Technical University of Denmark (DTU).