JOURNAL OF SUSTAINABLE ENERGY VOL. 5, NO. 3, SEPTEMBER, 2014 ISSN 2067-5534 © 2014 JSE ANALYSIS ON THE ENERGY PERFORMANCES OF OTL TRAMS FELEA I.*, CSUZI IS.**, DAN F.*, CHIREA V.* * University of Oradea, University Street, No. 1, Oradea ** Oradea Public Transport Company, (OTL S.A.) ifelea@uoradea.ro Abstract - This paper summarizes the results obtained from measurements carried out on trams operated with DC motors at the request of Oradea Transport Company (OTL). It aims on achieving a comparative analysis electrically driven trams (EDT) with d.c. motors (DCM), in terms of energy performance, based on a defined synthetic indicator and evaluated in the paper. The paper is structured in four parts. After presenting the importance of this analysis, through the significant use of electric energy (EE) in urban public transport and a brief description of the system under analysis, the second part of the paper presents the workings and results with respect to 21 pieces of EDT- DCM. Comparative interpretation of the results and conclusions of the analysis are contained in Part three of the paper and in the last part is specified the need and how to further research this area. Keywords: trams, energy performance, power auditing. 1. INTRODUCTION Sustainable development is one of the dominant themes of globalisation. Transport and energy are two key challenges in the sustainable development strategy of the EU [1]. It is known that at the EU level, the power consumption in systems of transport is of about 30 % of all consumption, greenhouse gas emissions caused by the means of transport being as [2]. Therefore, it is clear that environmental concerns with regards to reduce energy consumption in the transport systems are very important and entered the main concerns to increase the social, economic and environmental performance of these systems [3,4]. Operating concept and targets on the sustainable development, for energy-intensive processes, including those of transport, results through the reduction of fossil fuel consumption in two ways: a) increasing the efficiency of energy processes; b) increasing the use of renewable energy sources. Targets and pathways to the action of the European Union are very clearly defined and regulated [5, 6] aimed essentially to the reduction by 2020 of the energy consumption from fossil fuels by 20% and increase the share of renewable sources by 20%. In Romania, energy efficiency is much lower than in other countries with top-of-the-line technology. Still, many processes and technology services exist. In Romania, these take place with energy intensity of [2 ÷ 3] times greater than similar processes modernised in the "flagship" countries under technological aspect. In the last period, legislative and financial efforts are made [7,8] for the alignment of the Romanian status to European standards, not only by the appearance of energy efficiency but also under the aspect of renewable resource usage. From perspective of sustainable development, it is essential that local official have to pay attention to: • Development takes priority over urban public transport (UPT), which will reduce auto traffic with all the implications; • Development of electrified UPT, transport system which is much cleaner, is relatively quiet and enhanced safety in circulation. Specific problems of urban public transport systems are reflected in literature on the subject. A significant part of work aims the performance of UPT systems, performance quantified by: efficiency, quality of service, impact to the environment. In [4,9] one identified factor which influence the application of the UPT with a particular focus, specially, on the quality service, and in [10] one proposed and exemplified a methodology applied in the preparation of studies of quality of the UPT system. Detailed methodology for the assessment of quality of the service of transport shall be made in [11,12], out using the deciding factors of impact such as: availability, comfort, and convenience. Availability of the transmission system is examined in terms of frequency of the service zone and service coverage. For a system of UPT with buses shall be analysed comfort and convenience. Effectiveness of concrete UPT systems is analysed for example in [12,13,14]. The authors work [12] analysed, compared, UPT with buses and trolleybuses, assuming that the variance of the UPT is a complex problem, dependent on many economical, technical and eco-friendly factors. Performed analysis show that the containing values obtained for the two variants, include specific consumption of energy, and are very close. Thus, in [13] one shall assess the effectiveness of the UPT systems of 12 cities in Europe and 7 in Brazil. On the basis of results obtained, the authors get to the conclusion that, in nine cities in Europe, and in one of Brazil UPT is effective; the inefficiency is due to social interferences. The energy efficiency of UPT with electric traction is presented in [14]. It aims at determining energy efficiency for locomotives and its impact to the optimization of the running lines parameters, the modernisation of the stations and optimal management of traffic.