Monitoring energy poverty in Northern Greece: the energy poverty phenomenon

The last two decades’ scientists have become increasingly interested in the aspects of energy poverty. In order to study the dynamics of energy poverty in Northern Greece a field study was carried out. The evidence presented is based on a comprehensive study of 350 questionnaires mainly for Western (47%) and Central Macedonia (45%), in Northern Greece. The questionnaire focused on the household’ and users’ characteristics, allowing for regional specific effects. Additionally, in an effort to study and quantify the relation between households’ net-income and the most common indicators of energy poverty a Chi-square test was estimated. At the same time six temperature and humidity loggers have been distributed to selected participants to record real-time data. Overall, the results of the survey unveiled that various characteristics of the domestic demand for heating are linked with the household’s net-income.     

Building envelope design for climate change mitigation: a case study of hotels in Greece

This paper presents results of a study of the impact of future climate change scenarios as developed by the Intergovernmental Panel on Climate Change and implemented in weather files for specific future time slices (2020, 2050 and 2080) for the three climatic regions of Greece on the design of the external envelope of a hotel building in Greece. The impact of climate change on the hotel is assessed via hourly simulations of a calibrated model developed using the software TRNSYS. Additionally, the paper aims to identify optimal refurbishment strategies, given the constraints of the existing case-study building when transposed to the three different climatic zones in Greece. Two modes of the hotel building were studied: ‘all year’ and ‘seasonally’ operated. It was found that different external envelope energy-efficient strategies can be applied depending on the climatic zone and whether the hotel is all-year or seasonally operated.     

Economic growth,energy conservation and emissions reduction: A comparative analysis based on panel data for 8 Asian-Pacific countries

This study was conducted to evaluate the causality between energy consumption, GDP growth and carbon emissions for eight Asia-Pacific countries from 1971 to 2005 using the panel data. The results indicate that there are long-run equilibrium relationships between these variables. Additionally, causality from energy consumption to CO₂ emissions was observed generally, but there were some opposite relationships also. Parameter estimations of the panel data model indicate that there are great differences in the carbon emissions, the efficiencies of energy use, carbon emissions of unit GDP and unit energy consumption between developed and developing countries. The base carbon emissions, per capita energy consumption and efficiency of energy use in developing countries are far lower than in developed countries; however, the CO₂ emissions per unit of energy use is higher. Although developing countries may reduce their CO₂ emission per unit energy use, total energy consumption will rise rapidly with economic development. Thus, developing countries must determine how to undergo economic growth while conserving energy and reducing emissions. To respond to global climate change, it is necessary to develop innovative technology for energy use, transform the energy structure and conduct the clean development mechanism.     

A mathematical programming framework for energy planning in services’ sector buildings under uncertainty in load demand: The case of a hospital in Athens

The aim of this paper is to provide an integrated modeling and optimization framework for energy planning in large consumers of the services’ sector based on mathematical programming. The power demand is vaguely known and the underlying uncertainty is modeled using elements from fuzzy set theory. The defined fuzzy programming model is subsequently transformed to an equivalent multi-objective problem, where the minimization of cost and the maximization of demand satisfaction are the objective functions. The Pareto optimal solutions of this problem are obtained using a novel version of the ε-constraint method and represent the possibly optimal solutions of the original problem under uncertainty. In the present case, in order to select the most preferred Pareto optimal solution, the minimax regret criterion is properly used to indicate the preferred configuration of the system (i.e. the size of the installed units) given the load uncertainty. Furthermore, the paper proposes a model reduction technique that can be used in similar cases and further examines its effect in the final results. The above methodology is applied to the energy rehabilitation of a hospital in the Athens area. The technologies under consideration include a combined heat and power unit for providing power and heat, an absorption unit and/or a compression unit for providing cooling load. The obtained results demonstrate that, increasing the degree of demand satisfaction, the total annual cost increases almost linearly. Although data compression allows obtaining realistic results, the size of the proposed units might be slightly changed.     

A multiple objective decision making model for energy generation portfolio under fuzzy uncertainty: Case study of large scale investor-owned utilities in Florida

The objective of this paper is to present a methodology to evaluate the viability of developing solar photovoltaic projects for large investor-owned utilities. By taking into account the trade-off between the cost per kWh of electricity generation and total risk for an investor-owned utility, a multi-objective model of the energy generation portfolios is developed. The decision making model can determine the proportion of different energy generation sources in an investor-owned utility portfolio that reduces risk while providing the lowest cost per kWh of electricity generation possible. In order to measure the risk of the investor-owned utility for energy portfolio selection, an investigation of possible dangers and failures of energy generation portfolios is made and 9 main failure modes are identified. The failure mode and effects analysis is employed to calculate the risk priority numbers for each risk. To deal with the uncertainties of the levelized cost of electricity and risk levels of failure modes, the fuzzy method is introduced and an equivalent crisp model is derived which is then solved by employing a multiple objective particle swarm optimization algorithm. The analysis for four large scale investor-owned utilities in Florida is presented to highlight the performance of the developed optimization method.     

The role of hydrogen in the road transportation sector for a sustainable energy system: A case study of Korea

This study analyzes the impact of the introduction of hydrogen as fuel in the road transportation sector of Korea. Since this sector is completely dependent on petroleum and alternative technologies such as fuel cell vehicles, hydrogen is one alternative fuel that could meet the challenges that Korea is facing due to rising oil prices. This study uses a scenarios-based energy economic model including the hydrogen path way as a sub-energy system to explore the energy system of Korea through 2044. This study also constructs six scenarios consisting of three government policies concerning carbon dioxide reduction and two oil price scenarios in order to assess the impact on hydrogen as fuel in the road transportation sector. The results of this study show that in a particular case (high Btu tax and oil prices) the share of hydrogen would reach 76% of the road transportation sector, and hydrogen would be produced mainly from renewable and nuclear resources via electrolysis facilities. It is also revealed that hydrogen is effective at reducing carbon dioxide, improving energy efficiency and contributing to the energy security of Korea.