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Abstract: Increasing pressures from energy price and environmental directive force the manufacturing enterprises to consider and initiate the implementation of energy assessment and energy quota practices to improve both their economic benefit and environmental performance. Against this background this paper presents an integrated method to evaluate energy efficiency in machining workshop. The integrated features of the assessing method are reflected in three aspects: (1) In this evaluation system, the energy profile of machining workshop is viewed from the machine tool layer, manufacturing unit layer, task layer and workshop layer to reveal the energy performance inside the workshop completely. (2) The assessing indexes for each layer include both effective energy indicator and Specific Energy Consumption (SEC) indicator. (3) An integrated calculation method of energy indexes is introduced, which combines off-line experiments with theoretical formulas. To verify its feasibility and validity, the assessment method is applied to a small machining workshop. The assessing results showed that the assessment method is helpful in providing support for machining scheme selection, energy saving discovery and energy quota allocation in plant, which has significance in practice. [Copyright &y& Elsevier]

Abstract: The vegetable oil industry is considered as one of the major industries contributing to energy consumption in Iran. Despite the increasing need to improve energy efficiency in this industry, previous studies show that energy-efficient technologies have not been applied in most plants and other energy efficiency measures have not yet been adopted. Accordingly, this paper addresses the implementation of energy efficiency measures in the vegetable oil industry. Using a data envelopment analysis (DEA), the relative efficiency of plants in the vegetable oil industry is compared at different stages of the implementation of energy efficiency measures. The most effective indices for improving energy efficiency were identified and a model was designed to implement energy efficiency measures in industrial plants. In the model, the implementation process consisted of 5 stages, each of which had its own inputs and outputs. A multi-stage DEA model was employed to evaluate the performance of vegetable oil plants at each individual stage as well as the aggregate efficiency of each plant. After estimating the total efficiency of all plants and evaluating performance at the individual stages for each plant, the plants with ideal conditions for implementing energy efficiency measures were identified. These plants can serve as a benchmark for other plants. Estimation of the average efficiency across plants at each stage indicated that the plants suffered from poor performance in the first and fourth stages. Therefore, the results of this study indicate a need to develop new strategies for improving energy efficiency at these two stages. [Copyright &y& Elsevier]