561 research outputs found
A new method to energy saving in a micro grid
Optimization of energy production systems is a relevant issue that must be
considered in order to follow the fossil fuels consumption reduction policies and CO2 emission
regulation. Increasing electricity production from renewable resources (e.g., photovoltaic
systems and wind farms) is desirable but its unpredictability is a cause of problems for the
main grid stability. A system with multiple energy sources represents an efficient solution,
by realizing an interface among renewable energy sources, energy storage systems, and
conventional power generators. Direct consequences of multi-energy systems are a wider
energy flexibility and benefits for the electric grid, the purpose of this paper is to propose
the best technology combination for electricity generation from a mix of renewable energy
resources to satisfy the electrical needs. The paper identifies the optimal off-grid option
and compares this with conventional grid extension, through the use of HOMER software.
The solution obtained shows that a hybrid combination of renewable energy generators at
an off-grid location can be a cost-effective alternative to grid extension and it is sustainable,
techno-economically viable, and environmentally sound. The results show how this innovative
energetic approach can provide a cost reduction in power supply and energy fees of 40%
and 25%, respectively, and CO2 emission decrease attained around 18%. Furthermore, the
multi-energy system taken as the case study has been optimized through the utilization of
three different type of energy storage (Pb-Ac batteries, flywheels, and microâCompressed Air
Energy Storage (C.A.E.S.)
Improving building energy efficiency: case study
The main purpose of this study was to conduct a study for improving energy efficiency of an important building in Rome, the Headquarters of the Italian State Monopoly. The study was conducted by comparing conventional analysis tools with innovative ones, in order to evaluate the possible solutions, both structural and plant, aimed at the use of renewable sources and at energy saving. After making a thermo graphic survey, the first and useful step for a good energy audit, conduct building energy was simulated, at first in steady state by the use of a software widely used at the professional level, then in transient state by the use of TRNSYS, a finite difference method software which is able to simulate more accurately conduct building energy. The next step was to propose possible redevelopment of a structural and energy plant that promotes the building energy rating higher, finding the right balance between the energetic and economic aspect. Among the interventions plant, two possible workarounds have been proposed and designed in detail:
- installation of a photovoltaic system;
- installation of a solar cooling system.
Both solutions lead to a reduction of electricity consumption with a significant impact in economic and environmental term
Solar cooling: a case study
Throughout the years various methods for heat prevention and indoor temperatures control in
the summer have been used. The alternative cooling strategies are based on various passive and low
energy cooling technologies for protection of the buildings via design measures or special components
to moderate the thermal gains, or to reject the excess heat to the ambient environment. All these
techniques aim to reduce summer cooling loads and electricity demand for air conditioning. During
the summer the demand for electricity increases because of the extensive use of heating ventilation air
conditioning (HVAC) systems, which increase the peak electric load, causing major problems in the
electric supply. The energy shortage is worse during âdryâ years because of the inability of the
hydroelectric power stations to function and cover part of the peak load.
The use of solar energy to drive cooling cycles for space conditioning of most buildings is an
attractive concept, since the cooling load coincides generally with solar energy availability and
therefore cooling requirements of a building are roughly in phase with the solar incidence. Solar
cooling systems have the advantage of using absolutely harmless working fluids such as water, or
solutions of certain salts. They are energy efficient and environmentally safe.
The purpose of this paper is to describe a Solar Cooling System to be installed on the roof of a
building in Rome, the headquarters of the State Monopoly. The medium size power plant is composed
of the following components:
â Solar Collectors;
â Thermal Storage Tank;
â Absorption Chiller;
The plant design is based on a dynamic simulation in TRNSYS, a dynamic simulation tool used
by engineers all over the world to make energy calculations in a transient state
Energy study of a non-residential and historic building in transient conditions
The purpose of this manuscript is to analyse the interventions of energy retrofit
of a non-residential and historic building, through dynamic simulation by the use
of the TRNsys code. The study is made up of some steps:
- the analysis of the building and utility data, including study of the
installed equipment and analysis of energy bills;
- the survey of the real operating conditions;
- the selection and the evaluation of energy conservation measures;
- the identification of interventions of energy retrofit;
- TRNsys simulation of the effects of these interventions on the energy
behaviour of the building.
The present paper aims to present the results of the study, to discuss the expected
energy behaviour of the building and to comment on the options for introducing
energy conservation technique
Alien Registration- Romagna, Virginia (Portland, Cumberland County)
https://digitalmaine.com/alien_docs/25405/thumbnail.jp
Copyright Law in a Social Media World
There is no denying that social media has taken over our society. Even those who are not well versed in social media have a basic understanding of what it does and how it operates. With this emergence of social media, each industry has had to adapt practices and policies in order to comply with social media and to âkeep up with the timesâ and with the law. The legal world is one that is still trying to navigate through the waters of social media, and they have done so by creating âsocial media lawâ. These laws directly effect copyright law, as many things posted on the internet now face the question of whether or not they are protected by traditional copyright laws or whether they fall under fair use standards.
This post was originally published on the Cardozo Arts & Entertainment Law Journal website on March 13, 2017. The original post can be accessed via the Archived Link button above
A new tri-generation system: thermodynamical analysis of a micro compressed air energy storage
There is a growing interest in the electrical energy storage system, especially for matching intermittent sources of renewable
energy with customersâ demand. Furthermore, it is possible, with these system, to level the absorption peak of the electric network
(peak shaving) and the advantage of separating the production phase from the exertion phase (time shift). CAES (compressed air
energy storage systems) are one of the most promising technologies of this field, because they are characterized by a high reliability,
low environmental impact and a remarkable energy density. The main disadvantage of big systems is that they depend on geological
formations which are necessary to the storage. The micro-CAES system, with a rigid storage vessel, guarantees a high portability of the
system and a higher adaptability even with distributed or stand-alone energy productions. This article carries out a thermodynamical
and energy analysis of the micro-CAES system, as a result of the mathematical model created in a Matlab/SimulinkÂź environment.
New ideas will be discussed, as the one concerning the quasi-isothermal compression/expansion, through the exertion of a biphasic
mixture, that will increase the total system efficiency and enable a combined production of electric, thermal and refrigeration energies.
The exergy analysis of the results provided by the simulation of the model reports that more than one third of the exergy input to the
system is lost. This is something promising for the development of an experimental device
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