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The Ballast Water Management Convention (BWMC) was introduced by the International Maritime Organization (IMO) and it aims at minimizing the transfer of pathogens micro-organisms to the sensitive ecological marine areas, through the ballast of the oceangoing ships. Although it is expected to be enforced worldwide, there are some concerns about the technical requirements of the BWMC and in particular, the application of the Ballast Water Treatment Systems (BWTS) onboard ships. Up to date, there is not sufficient data regarding the performance of existing BWTS making an obstacle to their approval requirement by some states. In this paper, the methodology which is proposed involves expert judgement, utilized for the selection of the BWTS by a ship operator. As an essential part of the research methodology, the TOPSIS and the Analytic Hierarchy Process (AHP) are combined, to determine a cost-benefit decision-making tool, which would be applicable for the ship operators. In this paper, a case study is carried out, showing the potentials of the methodology and evaluating the choice of a BWTS for ships, trading in the USA. [ABSTRACT FROM AUTHOR]

Data centers are estimated to have the fastest growing carbon footprint from across the whole information and communication technology (ICT) sector. Evaluating the performance of data centers in terms of energy efficiency and sustainability is becoming an increasingly important matter for organizations and governments (e.g., for regulation or reputation purposes). It nonetheless remains difficult to achieve such evaluation, as data centers imply to take into consideration a wide range of dimensions and stakeholders. Even though a wide range of sustainability performance indicators exist in the literature, there is still a lack of frameworks to help data center stakeholders (spanning from data center owners, governmental regulators to engineers/field operators) to evaluate and understand how a data center performs in terms of sustainable development/behavior. Our research work proposes such a framework, whose originality lies in the combination of state-of-the-art sustainability metrics with the biomimicry commandments of eco-mature system, which enables holistic sustainability assessment of data centres. From a theoretical perspective, the proposed model is designed based on a benefit-cost analysis using the Analytic Hierarchy Process (AHP) technique. This approach allows data center stakeholders for specifying their own preferences and/or expertise in the comparison process, whose practicability is demonstrated in this paper considering three data center candidates, which are respectively located in France, Germany and Sweden. • A new model for comparing data center sustainability performance is proposed. • The model makes use of state-of-the-art sustainability metrics together with biomimicry lessons. • The model is designed based on a benefit-cost approach using the AHP technique. • A comparison study is carried out with three distinct data center candidates. [ABSTRACT FROM AUTHOR]

Building intelligent system has become one of the standard configurations in a public building even in a residential building. Intelligent buildings are expected to provide high-efficient, convenient, comfortable and energy-saving built environment so as to bring additional benefits. However, problems like sensor faults and control strategy flaws may result in low performance and high energy consumptions and maintenance costs are needed as well. Thus it is needed to synthetically evaluate the costs and benefits of intelligent systems to help building investors to make decisions. This paper proposes a cost-benefit evaluation method for building intelligent systems. Life cycle net present value (NPV) of all the costs and benefits, including tangible and intangible, is used as an index to evaluate the performance of the building intelligent systems. The proposed method puts emphases on the quantitative evaluation of intangible benefits using Analytical Hierarchy Process (AHP) method to determine the weights of each aspects of intangible benefit. The building energy consumptions are taken as an another emphasis as well. The proposed method is applied to evaluate three actual buildings to check its feasibility and effectiveness. Sensitivity analysis of NPV to energy consumption of the case study buildings shows that the energy consumption increase or decrease caused by different performances of intelligent systems can influence the positive or negative of NPV, which implies the building intelligent systems are worth of investment or not. [ABSTRACT FROM AUTHOR]

In this paper, cost-benefit analysis is performed to compare eight different hydrogen production technologies using the classical analytic hierarchy process (AHP) and the Fuzzy AHP. The technologies considered are steam methane reforming, coal gasification, partial oxidation of hydrocarbons, biomass gasification, photovoltaic-based electrolysis, wind-based electrolysis, hydro-based electrolysis, and water splitting by chemical looping. For each of the hydrogen production technologies, five criteria are used for evaluation: greenhouse gas emissions, raw material and utilities consumption, energy efficiency, scalability, as well as waste disposal and atmospheric emissions. The results obtained for benefits category using AHP and Fuzzy AHP are plotted against the normalized equivalent annual costs of each technology. It is concluded that the fossil fuel based processes appear to have less beneficial qualities including greater environmental impacts, but are more cost-effective. On the other hand, the renewable based processes appear to have more benefits as well as being more expensive for hydrogen production. However, the cost-benefit analysis results imply that the process of water splitting by chemical looping among the renewable approaches is the most promising new technology. [ABSTRACT FROM AUTHOR]

Malaysia's renewable energy policies do not cover production from waste, including the generation of biogas from palm oil mill effluent. This paper combines life cycle cost-benefit analysis (LCCBA) and the analytical hierarchy process (AHP) to provide new insights into costs and benefits of technologies over the life cycles, and on the basis of this information, asks experts to rank different options to enhance policy. The results show that the continuous stirred tank reactor has a higher LCC of 0.63 Million USD/year, compared to a LCC value of 0.55 Million USD/year for the covered lagoon bio-digester. In terms of cost-benefit, the continuous stirred tank reactor has a higher net present value of 0.46 Million USD/year, higher return on investment of 10.11% and a shorter payback period of 9.9 years compared to the covered lagoon bio-digester system, which has a net present value of 0.22 Million USD/year, return on investment of 7.79% and a payback period of 12.8 years. The continuous stirred tank reactor system therefore emerges as more economically feasible compared to the covered lagoon bio-digester system. On providing this information to experts using AHP, the three top ranked policy options emerged as: i) providing detailed environmental guidelines, ii) standardising technical guidelines for biogas installation and iii) covering the open pond wall using lining. Economic insights and policy opportunities based on this research can be used to inform policy decision making in multiple contexts where biogas plant projects are under consideration, in both Malaysia and globally. • Life cycle cost-benefit analysis (LCCBA) on palm oil mill effluent treatment. • Analytical hierarchy process (AHP) ranks policy options. • Combining LCCBA and AHP offers insights linking economic analysis & policy options. [ABSTRACT FROM AUTHOR]