Solar energy technologies in sustainable energy action plans of italian big cities

Cities, accounting for more than 3/4 of global final energy consumption, are equipping themselves with governance tools to improve energy efficiency. In Europe, urban energy policy has adopted, only recently and voluntarily, the Sustainable Energy Action Plans (SEAP), following the European Strategy 20-20-20. Italy, country most sensitive among European ones, accounts for 53% of SEAPs signatories. In order to evaluate how urban energy system in Italy can match sustainability European goals, it is necessary to analyse the technological options promoted by the energy policies for the urban environment. The paper presents the state-of-art of Urban Energy Planning in Italy, focusing on the implementation of Solar Energy technologies, and their role in new urban energy strategy instruments, i.e. SEAP, to promote renewables deployment. Carbon emission avoidance interventions planned by Italian big cities were analysed, highlighting the chosen Solar Energy technology. The aim of this paper is to discuss and evaluate the differences of solar energy harvesting in Italian urban scenarios, taking into account geographical and morphological constraints, and to compare the forecasts for 2020 and 2030scenarios, in accordance with European and National laws in force

E2VENT – design and integration of an adaptable module for residential building renovation

The paper presents an innovative approach to the retrofitting of the adaptive ventilated facade module developed in the EU project E2VENT.  The E2VENT innovative facade module is targeted to Optimal Adaptability and Heat Exchange for the refurbishment of existing buildings and is composed of two main parts: an adaptable smart modular heat recovery unit (SMHRU), which is adjustable to work within the ventilated façade cavity, is able to recover heat from ventilation air, and can preheat ventilation air in winter while precooling it in summer; and a latent thermal heat energy storage system (LTHES) which is based on phase change materials fitting in the cavity and is complementary to the SMHRU. Following a brief introduction of the E2VENT project, the integration of the new technology at the building scale, and analysis of the foreseen design issues in terms of interfaces and façade singularities shall be discussed.  The paper will discuss how the systemic managing of these issues at the design level is vital in preventing inconsistencies between parts and helps with the design team working process

Effect of soiling on solar photovoltaic performance under desert climatic conditions

The solar irradiation at the gulf Arabia is considered one of the highest in the world. However, this region is classified as a desert with high dust accumulation. Thus, the objective of this study is to analyze the effect of soiling and the photovoltaic (PV) tilt angle on the performance of 2.0 MWp of car park PV plant in Oman. Experimental measurements were taken and a model was developed for simulation. The power generation by the cleaned PV system was measured as 1460 kW around noon. After one week of operation, the power production (at the same irradiance level) reduced to 1390 kW due to soiling. It further reduced to 1196 kW and 904 kW after three and five weeks of operation, respectively. The results also show that a soiling-percentage of 7.5% reduced the monthly electricity generation (307 MWh) by 5.6% and a soiling-percentage of 12.5% reduced the generation by 10.8%. Furthermore, the increase in tilt is not recommended due to the duo-pitch canopy effect of the car park where the panels with 180° azimuth generate lower electricity than the panels with 0° azimuth. In addition, the part of the car park with 180° azimuth caused shading to the other part for high tilt angles

AC vs. DC distribution efficiency:Are we on the right path?

The concept of DC power distribution has gained interest within the research community in the past years, especially due to the rapid prevalence of solar PVs as a tool for distributed generation in DC microgrids. Various efficiency analyses have been presented for the DC distribution paradigm, in comparison to the AC counterpart, considering a variety of scenarios. However, even after a number of such comparative efficiency studies, there seems to be a disparity in the results of research efforts, wherein a definite verdict is still unavailable. Is DC distribution a more efficient choice as compared to the conventional AC system? A final verdict is absent primarily due to conflicting results. In this regard, system modeling and the assumptions made in different studies play a significant role in affecting the results of the study. The current paper is an attempt to critically observe the modeling and assumptions used in the efficiency studies related to the DC distribution system. Several research efforts are analyzed for their approach toward the system upon which they have performed efficiency studies. Subsequently, the paper proposes a model that may alleviate the shortcomings in earlier research efforts and be able to give a definite verdict regarding the comparative efficiency of DC and AC networks for residential power distribution

Advancements in Hydropower Design and Operation for Present and Future Electrical Demand

With current infrastructure, meeting the ever-growing demand for electrical energy across the globe is becoming increasingly difficult. The widespread adoption of both commercial and residential non-dispatchable renewable energy facilities, such as solar and wind, further taxes the stability of the electrical grid, often causing traditional fossil fuel power plants to operate at lower efficiency, and with increased carbon emissions. Hydropower, as a proven renewable energy technology, has a significant part to play in the future global electrical power market, especially as increasing demand for electric vehicles will further amplify the need for dispatchable energy sources during peak charging times. Even with more than a century of proven experience, significant opportunities still exist to expand the worldwide hydropower resources and more efficiently utilize existing hydropower installations. Given this context, this Special Issue of Energies intended to present recent developments and advancements in hydropower design and operation. This Special Issue includes five articles, authored by international research teams from Japan, Pakistan, Sweden, Norway, the United States, and China. The authors bring the collective expertise of government research laboratories, university professors, industry research engineers, computer scientists, and economists. The articles explore advancements in hydroturbine and pump-turbine design, power plant operation, auxiliary equipment design to mitigate environmental damage, and an exploration of community-owned small hydropower facilities

Progress in research and technological developments of phase change materials integrated photovoltaic thermal systems : The allied problems and their mitigation strategies

The efficiency of solar cells and photovoltaic (PV) panels are lacking significantly due to its surface overheating by the incident solar radiation. Indeed, the generated heat energy is harnessed by integrating a thermal system into PV panel, which introduces a photovoltaic thermal (PVT) system. Phase change materials (PCM)s are a class of energy material that is intended to facilitate thermal regulations of photovoltaic (PV) panel. Despite, PVT systems are allied with numerous problems like, integration technique, increase in overall weight of the system, dust accumulation, complication of tracking etc., which are of utmost importance to be resolved. The foremost aim of the review is to analyze the current technologies and allied problems of PVT system, the impact of the overall weight of the system on the PVT systems, detailed assessment of recent advancements in soil mitigation techniques, and the economic benefit of the PVT systems. Also, this review article is specifically intended to discuss on a) concerns allied with PV and PVT system integrated with PCM for thermal regulation; b) framework intimidating the performance of PCM-integrated PVT system; and c) mitigation techniques to resolve the problems and enhanced the performance of PCM integrated PVT system. A elaborative technical exploration on common issues associated with both PV and PVT systems in terms of surface cleaning towards dust mitigation via advanced mechanisms and futuristic technologies is comprehensively presented. A new possible sustainable solution towards enhancing the performance of PV and PVT systems is also provided. A summary of numerous research works conducted on enhancing the performance of PVT system integrated with PCM at different global locations is summarized. Furthermore, this review also discusses the economic analysis of PVT system integrated with PCM along with a summary of technical challenges and future outlook of PCM integrated PVT system to boost sustainable development