INTEGRATED DESIGN OF ALTERNATIVE ENERGY OPTIONS - A MULTICRITERIA APPROACH

Energy planning has come a long way during the 20th century from an intuitive approach to a full-scale discipline, incorporating technological and economic dimensions. The latter include both the micro- and the macro- level, whereas the technological framework covers energy, technology, thermodynamics and thermo-economic approaches. It is only during the last two decades that the environmental aspects of energy conversion has started to assume the gravity that it should have been assigned perhaps from the start, with the deterioration of the environment, e.g. acid rain, urban pollution, global warming, etc. and the depletion of resources becoming issues of outmost importance. The emergence of the renewable energy technologies as a reliable substitute of conventional fossil fuels gave promises that were only partially fulfilled as they never assumed the role that society had entrusted on them in the beginning. The alternative energy options, both on the technological and the resource level, revealed the complex nature of energy planning, where energy production and conversion should be addressed in tandem with energy demand and consumption and the particular preferences of the individuals. In both cases the spatial elements should be carefully analyzed and taken into consideration. Today’s energy planning asks for a complex approach which must includes the technological, economic, environmental and social design, accounting for the multitude of facets that interweave in the analysis and successful implementation of energy policies and projects. The aforementioned four dimensions must in turn be decomposed in a number of attributes in order for a quantitative and qualitative estimation to be realized. For the identification of an appropriate solution, a multi-criteria analysis seems to be the logical framework since it allows for a multitude of elements to be incorporated, and at the same time it can include a variety of stakeholders, with conflicting perhaps interests. In this paper we present the new approach for energy planning with the technological, economic, environmental and social design dimensions integrated in a new platform together with the necessary decomposition analysis. The whole new framework is presented via theoretical and practical examples and will hopefully pave the way towards a new under transition, energy future.

Sustainable Design of Energy Systems - The Case of Geothermal Energy

Geothermal energy is one of the renewable energy resources with a vast potential. It is extended spatially in many areas, isolated from urban areas and direct uses, whereas its utilisation when it is not for electricity production is many times hampered due to lack of a proper development framework. In this work we present a design framework for sustainable geothermal systems incorporating modules covering the various aspects of exploration, utilisation, end-use and management. The overall framework consists of the following sub modules: a. geophysical model of the assessment of the geothermal reservoir capacity b. model for the management of the geothermal wells, pumping and re-injection c. model for the distribution network d. model for the various end-uses, e. environmental model for sustainable operation The overall framework incorporates the basic axes of sustainable development, i.e. resources, economy, environment, energy, technology, society. The theoretical framework is applied to an existing geothermal reservoir which at the current is being underutilized, from an energy, environmental and economic perspective. The search for an optimum design includes the formulation of different scenarios and the multi-criteria decision analysis of them.

Transition towards decarbonisation for islands: Development of an integrated energy planning platform and application

This paper presents REACT-DECARB, an energy planning decarbonisation platform employing renewable energy sources coupled with storage for islands. The paper implements the energy scenario creation and economic evaluation steps of the platform on eight geographic islands in seven countries within the EU. Twenty-one technologically feasible energy scenarios, applicable to the specific conditions of each island, are specified and their economic assessment via a levelized cost of energy (LCOE) calculation is then performed. The main aim of this application is to verify the noted steps of the platform as well as to test its flexibility across geographically, socially and dimensionally disparate islands with various scenario generation methods. The results of the economic analysis show a wide variation of LCOE depending primarily on whether full island autonomy is assumed. In some cases the islands’ scenarios’ costs approach current market prices but are never below them; some scenarios are, however, below the current price of the island’s thermal generation. The sensitivity and uncertainty of the economic performance results’ and the variables used to calculate them are evaluated and discussed for two of the islands. The overall analysis and application has shown that the REACT-DECARB platform is suitable for different islands, regardless of location and size and can be useful for island energy planners

Future perspectives on sustainable tribology

AbstractThis paper highlights the future perspectives of sustainable tribology by examining the economic, environmental and social impact of three tribological case studies. One case study examines the sustainability and durability of micro-CHP systems looking the tribological phenomena generated within a scroll expander system. The scroll is the main part of a specific micro-CHP system and experiences wear and cavitation damage. The tribological optimization of the scroll expander improves the sustainability of the micro-CHP unit while it has a serious economic and environmental impact to the consumers and to the society in general. Another case study is focused on friction and wear performance of lifeboat launch slipways. The causes of high friction and wear during the RNLI's lifeboat launches along an inclined slipway are investigated with a view to reducing the environmental impact due to slipway panel wear and lubricant release into the marine environment. The project encompasses the sustainable design of slipway panels using design modifications based on tribological investigations to double their lifespan, while environmental and economic impact was significantly reduced by the use of biodegradable greases and water as lubricants. The final case study involves an investigation of recycled plastic materials to replace polyurethane used on skateboard wheels, scooters and similar applications. Polyurethane (PU) is difficult to recycle. With the dwindling resources and environmental problems facing the world today, recycling for both waste reduction and resource preservation has become an increasingly important aspect of sustainability. The tribological results showed that recycled polycarbonate plastic can effectively act as a substitute to polyurethane wheels. Moreover, sustainability considerations showing the environmental benefits of the use of recycled plastics over PU include reducing the CO2 footprint by 50% and the energy consumed by 60%, among other benefits. These case studies emphasise the importance of sustainable tribology in our epoch showing that increased sustainability performance can be achieved through tribology to a significant extent in many cases, providing stability to our world and more viable long term growth to our societies

Social impacts as a function of place change

This paper argues that both impacts felt by and attitudes to tourism are a function of place change. Destinations are comprised of three types of place: tourism, non-tourism and shared. It is believed attitudes are generally positive when stasis exists among the three types, but deteriorate during periods of rapid place change. Likewise, impacts are felt when place changes, especially when non-tourism place is transformed into either shared or tourism place. This proposition is tested through a meta-analysis of more than 90 journal articles examining social impacts of tourism. Nine types of place change were identified as well as a relationship between place change and lifecycle stage

Integration of the environmental management aspect in the optimization of the design and planning of energy systems

The increasing concerns regarding the environmental pollution derived from anthropogenic activities, such as the use of fossil fuels for power generation, has driven many interested parties to seek different alternatives, e.g. use of renewable energy sources, use of “cleaner” fuels and use of more effective technologies, in order to minimize and control the quantity of emissions that are produced during the life cycle of conventional energy sources. In addition to these alternatives, the use of an integrated procedure in which the environmental aspect will be taken into account during the design and planning of energy systems could provide a basis on which emissions reduction will be dealt with a life cycle approach. The work presented in this paper focuses on the examination of the possibilities of integrating the environmental aspects in the preliminary phase of the conventional design and planning of energy systems in conjunction with other parameters, such as financial cost, availability, capacity, location, etc. The integration of the environmental parameter to the design is carried out within a context where Eco-design concepts are applied. Due to the multi-parameter nature of the design procedure, the tools that are used are Life Cycle Analysis and Multi-criteria Analysis. The proposed optimization model examines and identifies optimum available options of the use of different energy sources and technologies for the production of electricity and/or heat by minimizing both the financial cost and the environmental impacts, with regard to a multiple objective optimization subject to a set of specific constraints. Implementation of the proposed model in the form of a case study for the island of Rhodes in Greece revealed that an optimized solution both cost and environmental-wise, would be an almost balanced participation of renewables and non-renewable energy sources in the energy mix

The Monetary Transmission Mechanism

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Tourism\u27s Perceived Social Impacts: The Case of Samos

This study investigates the impacts of tourism, as perceived by the residents of Pythagorion, a well-established tourism destination on the Greek island of Samos. Interviews conducted with heads of households revealed that residents not only supported the current magnitude of the tourism industry but also favored its expansion. Despite this, the respondents identified a number of negative tourism impacts, which, in their opinion, affected the town. These impacts included high prices, drug addiction, vandalism, brawls, sexual harassment and crimes. The study reconfirmed that those respondents who were economically dependent on tourism had more positive attitudes towards the industry than those who were not dependent on it

Tourism\u27s Perceived Social Impacts: The Case of Samos

This study investigates the impacts of tourism, as perceived by the residents of Pythagorion, a well-established tourism destination on the Greek island of Samos. Interviews conducted with heads of households revealed that residents not only supported the current magnitude of the tourism industry but also favored its expansion. Despite this, the respondents identified a number of negative tourism impacts, which, in their opinion, affected the town. These impacts included high prices, drug addiction, vandalism, brawls, sexual harassment and crimes. The study reconfirmed that those respondents who were economically dependent on tourism had more positive attitudes towards the industry than those who were not dependent on it