1,721,549 research outputs found
Vapor Pressure of Hydrofluoroolefins: Critical Review of Experimental Data and Models
Full text linkThis paper critically reviews vapor pressure data and vapor pressure models for seventeen hydrofluoroolefins, including R1234yf and R1234ze(E), and presents Wagner-type vapor pressure correlations for the seventeen hydrofluoroolefins
LNG as vehicle fuel and the problem of supply: The Italian case study
No full textThe transport sector represents a major item on the global balance of greenhouse gas (GHG) emissions.
Natural gas is considered the alternative fuel that, in the short-medium term, can best substitute
conventional fuels in order to reduce their environmental impact, because it is readily available at a
competitive price, using technologies already in widespread use. It can be used as compressed gas (CNG)
or in the liquid phase (LNG), being the former more suitable for light vehicles, while the latter for heavy
duty vehicles. The purpose of this paper is to outline the potential of LNG as vehicle fuel, showing
positive and negative aspects related to its introduction and comparing the different supply options with
reference to the Italian scenario, paying particular attention to the possibility of on site liquefaction. The
analysis has highlighted that purchasing LNG at the regasification terminal is convenient up to a terminal
distance of 2000 km from the refuelling station. The liquefaction on site, instead, asks for liquefaction
efficiency higher than 70% and low natural gas price and, as liquefaction technology, the let-down plants
at the pressure reduction points along the pipeline are the best option to compete with direct supply at
the terminal
Air conditioning installaion with cooling storage
No full textEuropean Seminar on Advanced Systems of Passive and Active Climatisation, Barcelona, Spain, June 199
Indirect cooling for display cabinets
No full text2nd Plenary Meeting - EU Concerted Action on "The preservation of Frozen Food Quality and Safety throughout the Distribution Chain", Montpellier, France, March 199
Distributed generation and trigeneration: energy saving opportunities in Italian supermarket sector
No full textThis paper presents an analysis of the potential for introducing distributed generation systems in the
supermarket sector in the light of Italian legislation (inasmuch as concerns tax incentives and regulations)
with a view to arriving at some generally applicable criteria. The energy users in question are
characterized by a strong demand for energy for refrigeration for food preservation and for ambient
air-conditioning during the summer.
This makes supermarkets particularly suitable for trigeneration applications with the prime mover
coupled with absorption systems. This study analyses the feasibility of implementing trigeneration systems
for the combined production of electricity and ambient heating and air-conditioning energy or,
alternatively, for the combined generation of electrical energy and refrigeration for the preservation of
food. Finally, the hypothesis of combining trigeneration systems with photovoltaic systems aimed at
maximizing the energy saving achievable was also considered. This paper analyses the various technologies
from a technical, economic and environmental standpoint, enabling advantages and disadvantages
to be identified in relation to a real case
The impact of renewable energy systems on local sustainability
No full textThe purpose of the paper is to discuss and assess the impact of renewable energy, RE, generation on sustainable communities, with a specific focus on employment impact. In recent years, local authorities have been involved in the energy planning process due to the site-specific nature of renewable production and thanks to their nearer connection to citizens. Four small and medium-size sustainable communities belonging to Marche region, in central Italy, have been analysed. The work forecasts the employment generated by the RE capacity defined by two different energy scenarios: 1) the 'business as usual' scenario with a 20% CO2 emission reduction target by 2020, where all the energy policies suggested by Sustainable Energy Action Plans have been considered; 2) the 'potential' scenario with a 50% CO2 emission reduction target by 2050. Results show that the spreading of renewable energy, as expected, can increase local jobs, although the high investments required and problems connected to the impact on the grid have to be considered in the analysis of the global economic effect
A MULTI-CRITERIA DECISION APPROACH TO CHOOSING THE OPTIMAL BLANCHING – FREEZING SYSTEM
No full textThe aim of this paper is to propose a structured approach for identifying the best, most efficient combination of blanching–freezing
system. The analysis was based on the well-known analytical hierarchy process multi-criteria decision method and led to the definition of a general decision hierarchy, which was applied to two case studies concerning shrimps and peas. The decision hierarchy and the results obtained were validated by a panel of experts and are thus suitable for use as a tool for food-processing experts
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