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Environmental restrictions get every day more demanding; therefore, energy policies focus on reducing greenhouse gas emissions, setting clear targets relative to the renewable energy contribution in meeting electricity demand. Thus, the global tendency towards fossil fuel replacement by renewable energy sources (RES) is progressively sharpening. Sustainability of power systems with high renewable energy penetration rates is a topic of major interest, especially considering the intermittency of RES production and the actual growing trend of energy consumption. Addressing such a complex concept requires particular designs approaches, taking into account several points of view (technical, economic, social). In accordance with the established objective (certain performance or quality indexes), multiple criteria should be selected and assessed so that the final project achieves long term sustainability. In the context previously described, design, operation and control of power systems are Multi-Criteria Decision Making (MCDM) processes and follow particular algorithms. This paper presents first a brief introduction, followed by a description of the most used MCDM algorithms for RES integration in power systems. Further, a case study is detailed, applying the above-mentioned algorithms to a small-scale system, comprising RES generating components and storage elements. Results are compared and discussed in the Conclusions section, highlighting also the different weights of each criterion in the final result. [ABSTRACT FROM AUTHOR]

The topic addressed in this paper is related to two waste management (poultry manure) objectives: reducing environmental impact through combustion, and energy generation. Poultry industry waste is produced in large amounts and cannot be always used as a fertilizer. Its storage needs large sites, but if they are improperly designed could affect the phreatic groundwater. The paper is organized as it follows. The first part presents the energy characteristics the waste samples analyzed (they come from a poultry farm, which beds the floor with cereal straw or sawdust; relatively to the waste mass, the bedding represents about 5% to 15%). The samples are taken from an intermediate warehouse located between the production halls and the central warehouse of a large capacity poultry farm. Regarding the location, the poultry farm is placed in the center of the historical region of Moldova, in Romania. From an exclusively energetic point of view, differences between the two beddings are not significant, since they both belong to the biomass class; if the biomass bedding lacks (very rare), the energy characteristics of the poultry manure get worse. The second part introduces a technology suitable for this kind of waste combustion. Starting from the energy properties, thermal conditions for ignition and flame support are investigated. The boiler types adequate for the process are specified, appropriate thermal power range is indicated. Considering the very difficult manipulation of this particular waste, its use is recommended for thermal energy production. Local utilization is taken into consideration, especially for heating purposes, for instance of the production halls. According to the results of this study, boilers equipped with mobile grate combustion installations and using gaseous or liquid hydrocarbons fuel aid are expected to have good yields for energetic valorization of poultry waste. [ABSTRACT FROM AUTHOR]

This paper addresses the possibility of using poultry manure pyrolysis to obtain energy- efficient products. Poultry manure pyrolysis is the intended technology of combustion for both ecological and energy generation purposes, obtaining coke and gas fuel. The waste subjected to pyrolysis had a behaviour very close to that of the inferior coal. This is also confirmed by the elemental analysis; high moisture value raising issues when direct combustion is used. The combustion of the poultry manure through various technologies, including pyrolysis, using also another fuel, is a secondary result. Waste management represents a current major concern, especially for modern society who faces the pressing problem of their storage. Thermal treatment is a solution adopted in several circumstances. The results obtained show that waste behavior is very close to that of inferior coal. Power consumption for pyrolysis process falls within satisfactory limits; bellow the heat obtained by burning pyrolysis products. Pyrolysis fuel products, represented by semi-coke and coke, are likely to be used to produce energy. The paper presents a practical way of economic and ecological exploitation of the garbage from the poultry farms. [ABSTRACT FROM AUTHOR]