The direct coupling of solar electricity with electric vehicles is very topical due to their many co-benefits, such as reducing the electricity flow into and from the grid. This work illustrates this ...solution using a park-and-ride lot outside Lisbon to study its solar energy potential to charge electric vehicles. The solar resource, its exploitation and coordination with the vehicles under different charging approaches are discussed in detail, using methods extendible to other cases. A genetic-algorithm optimisation was performed to maximise the solar energy generation. To ascertain the techno-economic feasibility of the concept, several sets of assumptions are analysed, including the use of energy storage and smart charging. For current market conditions, the payback time is found to be 14 years; a modest financial public incentive would significantly improve the project economics – making the payback drop to 7 years – enabling conditions to put this inescapable and green approach at the forefront.
•A solar carport viability for electric cars is studied using real occupation data.•Several scenarios are compared using energy and financial indicators.•The best-case uses a controlled charging and avoids the need of storage.•Public subsidies can significantly improve the attractiveness of the project.
In order to reach significant CO2 emissions reductions, future energy systems will require a large share of renewable energies, such as wind and solar photovoltaic power. However, relying on such ...renewable energy sources is expected to generate considerable excess power during certain periods of the day, in particular during night time for wind and daytime for solar power. This excess power may be conveniently used to power electric mobility. This paper explores the possible complementarities between wind and solar power and electric vehicles charging, based on 2050 scenarios for the case study of Portugal. Model results show that CO2 emissions targets can only be achieved with high levels of photovoltaics penetration and electric vehicles, reinforcing the need for daytime charging infrastructures, presumably at or near work facilities.
•We model an energy system with significant electric mobility.•We assess complementarity between wind and solar power and electric vehicles charge.•The electric vehicle demand leads to a reduction of excess production of electricity.•CO2 emissions targets can only be achieved with high levels of PV (photovoltaic) penetration.•Most of the electric vehicle charging will have to take place during working hours.
Human iPS cells have been generated using a diverse range of tissues from a variety of donors using different reprogramming vectors. However, these cell lines are heterogeneous, which presents a ...limitation for their use in disease modeling and personalized medicine. To explore the basis of this heterogeneity we generated 25 iPS cell lines under normalised conditions from the same set of somatic tissues across a number of donors. RNA-seq data sets from each cell line were compared to identify the majority contributors to transcriptional heterogeneity. We found that genetic differences between individual donors were the major cause of transcriptional variation between lines. In contrast, residual signatures from the somatic cell of origin, so called epigenetic memory, contributed relatively little to transcriptional variation. Thus, underlying genetic background variation is responsible for most heterogeneity between human iPS cell lines. We conclude that epigenetic effects in hIPSCs are minimal, and that hIPSCs are a stable, robust and powerful platform for large-scale studies of the function of genetic differences between individuals. Our data also suggest that future studies using hIPSCs as a model system should focus most effort on collection of large numbers of donors, rather than generating large numbers of lines from the same donor.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Climate influences renewable energy resources and energy demand, and therefore its interannual variability ought to be considered when designing future renewable-based power systems. This work models ...a 100% renewable power system considering 473 climate projections based on IPCC RCP4.5 and 8.5, using Portugal in 2050 as a case study. Five demand-flexibility scenarios are explored, combining different levels of electricity demand and system flexibility. It is found that demand and climate variability are crucial to the planning of power systems. When planning for a median climate, the required capacity varies 3-fold for the range of demand scenarios considered. For the system to be resilient under unfavorable climates, cross-border interconnection power capacity should be doubled while storage should increase up to 200-fold, compared to the system designed for the median climate. Modeling for unfavorable climates leads to +54% renewable power capacity and a 6-fold increase in curtailment of renewable energy generation, thus increasing electricity cost. It is therefore shown that the design of a fully decarbonized power system ought not to be based only on median future climates but should take into account its interannual variability.
•The resilience of a fully decarbonized power system is explored.•Climate variability and electricity demand scenarios are considered simultaneously.•A 3-fold increase on renewable capacity is required from low to high demand scenarios.•Twice as much cross-border interconnection capacity required for unfavorable climate than for median climate.•Unfavorable climate requires +54% renewable capacity than the median climate.
Summary
After the occurrence of various destructive earthquakes in Japan, extensive efforts have been made to improve the seismic performance of bridges. Although improvements to the ductile ...capacities of reinforced concrete (RC) bridge piers have been developed over the past few decades, seismic resilience has not been adequately ensured. Simple ductile structures are not robust and exhibit a certain level of damage under extremely strong earthquakes, leading to large residual displacements and higher repair costs, which incur in societies with less‐effective disaster response and recovery measures. To ensure the seismic resilience of bridges, it is necessary to continue developing the seismic design methodology of RC bridges by exploring new concepts while avoiding the use of expensive materials. Therefore, to maximize the postevent operability, a novel RC bridge pier with a low‐cost sliding pendulum system is proposed. The seismic force is reduced as the upper component moves along a concave sliding surface atop the lower component of the RC bridge pier. No replaceable seismic devices are included to lengthen the natural period; only conventional concrete and steel are used to achieve low‐cost design solutions. The seismic performance was evaluated through unidirectional shaking table tests. The experimental results demonstrated a reduction in the shear force transmitted to the substructure, and the residual displacement decreased by establishing an adequate radius of the sliding surface. Finally, a nonlinear dynamic analysis was performed to estimate the seismic response of the proposed RC bridge pier.
Solar energy forecasting is an active research problem and a key issue to increase the competitiveness of solar power plants in the energy market. However, using meteorological, production, or ...irradiance data from the past is not enough to produce accurate forecasts. This article aims to integrate a prediction algorithm (Smart Persistence), irradiance, and past production data, using a state-of-the-art machine learning technique (Random Forests). Three years of data from six solar PV modules at Faro (Portugal) are analyzed. A set of features that combines past data, predictions, averages, and variances is proposed for training and validation. The experimental results show that using Smart Persistence as a Machine Learning input greatly improves the accuracy of short-term forecasts, achieving an NRMSE of 0.25 on the best panels at short horizons and 0.33 on a 6 h horizon.
The decarbonization of the Portuguese electricity system, currently around 50% renewable-based, is undergoing with the commitment to reach 60% of renewable electricity share by 2020. Because of this, ...the phase-out of the two remaining coal-fired power plants has been receiving close attention, as they currently contribute to about one-fifth of the total electricity generation and two-thirds of the CO2 emissions in the power sector. This work assesses the impact of eliminating coal-fired generation from the Portuguese electricity system without replacing it, and explores a cleaner supply alternative achievable before 2025. Coal phase-out without substitution results in slightly increased CO2 emissions for the atmosphere if one assumes that the required additional imports are of carbon-intensive electricity, leading to the need of adding clean power capacity to the system. It is shown that coal plants could be replaced by about 8 GW of photovoltaics if accompanied by a modest increase in the already existing hydro pump capacity. In this case, the renewable electricity share increases to 77%, and carbon footprint decreases by 56%.
Display omitted
•Coal power plants still supply a fifth of the Portuguese electricity demand.•Coal power plants phase-out is tested, considering alternative supply sources.•Coal phase-out slightly increases CO2 emissions assuming carbon intensive imports.•Photovoltaics coupled with hydro pump can replace coal (−56% of CO2 emissions).•Photovoltaics with storage increases renewable electricity share from 50 to 77%.
•This work estimated PV energy potentials of building rooftops, walls and windows.•The analysis was conducted at various spatial resolutions from city to building scale.•Multiple urban form ...indicators were highly correlated with the PV energy estimates.•PV Production could cover up to 74% of electricity consumption in the City of Melbourne.•PV potential from windows became more prominent in central urban areas.
Many cities across the world are committing to deep decarbonisation efforts. While solar photovoltaics (PV) will play a critical role in this pursuit, the role of rooftop and facade-integrated PVs within the urban landscape is yet to be fully understood. This work presents an analysis into the solar energy harvesting potential of PVs integrated as building rooftops, walls, and windows at various spatial resolutions that range from city to building scale within the City of Melbourne, Australia, as a contemporary case study. It further investigates the relationship between calculated electricity production from such PVs with the urban morphology, seasonal variation and the measured electricity consumption by the local distribution network service providers. The results indicate that PV rooftops are responsible for the largest share of the city’s solar energy potential. However, for individual blocks with high densities of high-rise and glazed buildings, it is shown that the PV potential from windows becomes more prominent. The technical workflow presented here will enable different cities to facilitate decision-making on the PV implementation in urban environments.
The study of biliary disease has been constrained by a lack of primary human cholangiocytes. Here we present an efficient, serum-free protocol for directed differentiation of human induced ...pluripotent stem cells into cholangiocyte-like cells (CLCs). CLCs show functional characteristics of cholangiocytes, including bile acids transfer, alkaline phosphatase activity, γ-glutamyl-transpeptidase activity and physiological responses to secretin, somatostatin and vascular endothelial growth factor. We use CLCs to model in vitro key features of Alagille syndrome, polycystic liver disease and cystic fibrosis (CF)-associated cholangiopathy. Furthermore, we use CLCs generated from healthy individuals and patients with polycystic liver disease to reproduce the effects of the drugs verapamil and octreotide, and we show that the experimental CF drug VX809 rescues the disease phenotype of CF cholangiopathy in vitro. Our differentiation protocol will facilitate the study of biological mechanisms controlling biliary development, as well as disease modeling and drug screening.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
A flexible load management may improve significantly the economic dispatch, especially for isolated energy systems with a significant share of renewables. For that purpose, renewable resources and ...load forecasts ought to be taken in account for optimal demand response programs.
The present study uses solar forecast coupled with domestic hot water needs to anticipate the electric demand of solar thermal systems. On the other hand, wind electricity supply will take advantage of thermal storage of solar systems, using a demand response strategy based on genetic algorithms, for load optimization, in order to minimize overall operating costs. The methodology is applied to the isolated microgrid of Corvo Island, in Azores.
Results show a 3% increase in the dispatch costs due to the forecasts uncertainty, when in presence of 8% of daily flexible loads. However, this impact is dissipated when solar thermal backup needs decrease, which is explained by the relevance of the wind forecast on the planning of the dispatch of flexible loads. Wind forecast uncertainties can impact in 2% in absorption of wind energy, varying with the forecast horizon considered, while the solar forecast uncertainties have more impact when the thermal energy storage is below the daily thermal demand.
•Influence of forecast uncertainties on demand response optimization is studied.•A sensitivity analysis on forecast/dispatch planning parameters is done.•Uncertainties impact the dispatch costs on 3%, with 8% of daily flexible loads.•Wind forecast uncertainties can influence in 2% the wind absorption.•Solar forecast uncertainty influence, if thermal storage is below thermal demand.
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