Search results for " Energy Systems"
showing 10 items of 21 documents
Achieving maximum power transfer in a multi-source renewable system
2014
Investigating Potential Alignments between Modelica Standard Library and SAREF Ontologies
2021
International audience; Simulation tools based on the Modelica language provide comprehensive modelling and simulation approaches for building energy systems. However, the simulation and optimisation of such systems are data-driven processes, lacking a common understanding of information structure within the process. This paper investigates the possible semantic alignments of the Smart Appliances REFerence (SAREF) ontology and its extension for building domain, SAREF4BLDG, with the Modelica Standard Library (MSL). Using the MSL, a residential heating system has been modelled in OpenModelica, an open-source modelling and simulation environment. Then, SAREF and its extension SAREF4BLDG semant…
Flexibility Services to Minimize the Electricity Production from Fossil Fuels. A Case Study in a Mediterranean Small Island
2019
The design of multi-carrier energy systems (MESs) has become increasingly important in the last decades, due to the need to move towards more efficient, flexible, and reliable power systems. In a MES, electricity, heating, cooling, water, and other resources interact at various levels, in order to get optimized operation. The aim of this study is to identify the optimal combination of components, their optimal sizes, and operating schedule allowing minimizing the annual cost for meeting the energy demand of Pantelleria, a Mediterranean island. Starting from the existing energy system (comprising diesel generators, desalination plant, freshwater storage, heat pumps, and domestic hot water st…
Exergoeconomic analysis as a tool for supporting the design and operation of multiple chiller systems in air conditioning applications.
2019
Multiple-Chillers systems represent viable solutions for medium/large-scale air conditioning applications. In these systems, however, design and energy savings are highly affected by the configuration and operation strategies adopted. For instance, when considering multiple chillers of same size, “symmetric” or “sequential” load sharing strategies are two viable options. Conversely, when considering chillers of different sizes, a wide combination of chillers cooling capacities may be adopted. It is apparent that an integrated analysis of the design and operation of these systems should be carried out in order to achieve profitable energy saving. With this respect, Exergoeconomics, which res…
Environmental Assessment of a Hybrid Energy System Supporting a Smart Polygeneration Micro-grid
2022
To support the global transition towards a climate-neutral economy by 2050, countries all over the world are implementing low carbon and energy effi ciency policies. This is leading to a rapid increase in the installations of distributed generation technologies. A hybrid system consisting of two or more energy sources could provide a more reliable supply of energy and mitigate storage require ments. In this context, this paper develops an environmental early analysis by the employment of a simplified Life Cycle Assessment approach. The above mentioned approach is used to investigate the environmental performances of the hybrid energy system of the smart polygeneration micro-grid of the Univ…
Analysis of the effects of climate change on the energy and environmental performance of a building with and without onsite generation from renewable…
2020
Climate Change is a priority, due to the large variety of implications and importance that it may cause in the next decades. In this context, the building sector is a significant contributor to greenhouse gas emissions. For this reason, buildings should be designed in such a way that they are responsible for fewer GHG emissions. In this context, the paper analyses the potential impact of climate change on the energy performances of buildings, with and without onsite generation from renewable energy, using a prototype building located in Messina (Italy) as case study. The analysis is based on Intergovernmental Panel on Climate Change RCP scenarios and the results confirm the already known ov…
The interaction between intermittent renewable energy and the electricity, heating and transport sectors
2012
In a global perspective, it is essential that the world transfers from fossil fuels to renewable energy sources in order to minimise climate change effects. As a part of such transition energy savings are also important, as they can decrease production costs effectively. The nature of such a change is that it has to be implemented on a local level. Energy saving technologies are placed with the demand decrease and renewable energy is typically distributed where the resources are. In some parts of the world, energy savings have resulted in a stabilisation of the energy demands, however in the world as such, demands are still increasing in buildings, transport and industry. Although the deman…
DC Grids for Supporting AC Power System during Failure Events: Experimental Testing of a Urban Case Study
2022
AC power systems and their devices can be subjected to different failure events due to thermal, environmental, and aging phenomena. In this context, DC grids intervention could mitigate customers black-out by adequately controlling their internal resources (renewable generators and storage systems). In this paper, failure events concerning HV/MV transformer are considered. Possible actions to support the AC grid to avoid interruption in load areas are analyzed and experimentally validated. Tests campaigns are carried out taking advantage of a research nanogrid infrastructure available at ENEA Centre of Portici. It consists of indoor equipment able to emulate actual generation, load and stor…
Numerical and experimental investigation of a cross-flow water turbine
2016
ABSTRACTA numerical and experimental study was carried out for validation of a previously proposed design criterion for a cross-flow turbine and a new semi-empirical formula linking inlet velocity to inlet pressure. An experimental test stand was designed to conduct a series of experiments and to measure the efficiency of the turbine designed based on the proposed criterion. The experimental efficiency was compared to that from numerical simulations performed using a RANS model with a shear stress transport (SST) turbulence closure. The proposed semi-empirical velocity formula was also validated against the numerical solutions for cross-flow turbines with different geometries and boundary c…
Sustainable integration of Renewable Energy Systems in a Mediterranean island: a case study
2013
Starting from a previous technical and economical feasi-bility study, this paper analyzes the integration of Renewable Energy Sources into an existing territory with specified features of the natu-ral landscape and of the built environment. The work puts into evi-dence that territories development must use suitable tools and rules based on integrated knowledge, since technical feasibility studies do not assess the sustainability of the proposed infrastructures within the built environment and landscape. The studied system is in the is-land of Pantelleria situated between Sicily and northern Africa.