Life Cost Analysis Research Articles

Design of Electrical System for Offshore Wind Power Plant (OWPP)

The paper proposes a novel Optimum Frequency AC (OFAC) transmission system for reducing investment and operational cost of Electric System (ES) - integrating Offshore Wind Farm (OWF) to the onshore grid. Optimum operational frequency for ES is an inherent characteristic of the trade-off between its investment and operational cost. The paper presents a comprehensive methodology for the design of ES based on Life Cost Analysis using a Generic Algorithm. For the given offshore wind farm, alternative designs for ES are generated for different operational frequencies. Power system components of standard ratings are used for the designs. All the designs are evaluated in terms of~Net Present Values (NPV) and the design with maximum NPV is selected as the optimum solution. For 200 MW OWF, optimum operational frequencies are obtained as 50, 35, 25, and 50/3 Hz for offshore distances of 50, 100, 150, and 200 km, respectively. The results show that for 200 MW the feasible range for OFAC is 100-150 km and provides the saving of 5-10% as compared to High Voltage AC (HVAC) and Low-Frequency AC (LFAC). The results further indicate that for large-scale wind farms the saving increases substantially and the feasible range is reduced. It concludes that OFAC is an economical alternative to HVAC and LFAC for integrating large-scale OWF to the onshore grid and provides a new dimension for promoting Offshore Wind Power Plant (OWPP).

Techno-Economic Comparisons of HVAC and Simultaneous AC-DC Transmission

Electric power consumption has been increasing rapidly across the globe; this increase specially accelerated in the last decade. Consequently, existing transmission lines are becoming overloaded beyond their power transfer capability. The inadequacy of the transmission lines has contributed to power interruptions and instability of the power system. Construction of new transmission lines can be a solution to mitigate these problems. However, to build the whole structure of a new transmission line, a huge investment is required. Besides this, environmental concerns would create further barriers that delay the accomplishment of the project. Therefore, the effective and quickest solution to tackle this problem is enhancing the power transfer capability and stability margin of existing transmission lines. This paper studied the techno-economic feasibility of converting an existing HVAC line into a simultaneous AC-DC power transmission system to enhance power transfer capability as well as to improve power system stability. Using the proposed method, the loadability of Tana Beles to Addis Ababa 400 kV, 476.2 km AC line has increased to more than double which is from 1091.66 MW to 2196.85 MW. The active power loss and corona loss evaluation of the two systems ensured that simultaneous AC-DC system is more efficient than HVAC system. It is also shown that the instability can be effectively improved by simultaneous AC-DC power transmission with fast DC power modulation. From the economic point of view, rather than constructing new HVAC line, converting existing HVAC line into simultaneous AC-DC transmission system has a price reduction of about 107,984,968.56 USD or 32.46% of the new HVAC line cost. Considering a 35-year project life cost analysis, it is observed that the life cycle cost of the simultaneous AC-DC transmission system is about 29.2% lower than the life cycle cost of a new 400 kV HVAC line. Thus, the designed simultaneous AC-DC power transmission system has better technical performance and also is less costly than constructing a new HVAC line.

Urban Flood Risk and Economic Viability Analyses of a Smart Sustainable Drainage System

Urban drainage systems are in transition from functioning simply as a transport system to becoming an important element of urban flood protection measures providing considerable influence on urban infrastructure sustainability. Rapid urbanization combined with the implications of climate change is one of the major emerging challenges. The increased concerns with water security and the ageing of existing drainage infrastructure are new challenges in improving urban water management. This study carried out in the Seixal area in Portugal examines flood risk analyses and mitigation techniques performed by computational modelling using MIKE SHE from the Danish Hydraulic Institute (DHI). Several scenarios were compared regarding flood risk and sustainable urban drainage systems (SuDS) efficiency. To obtain a more accurate analysis, the economic viability of each technique was analyzed as well through (i) life cost analysis and (ii) taking into account the damages caused by a certain type of flood. The results present that the best scenario is the one that will minimize the effects of great urbanization and consequently the flood risk, which combines two different measures: permeable pavement and detention basin. This alternative allows us to fully explore the mitigation capacity of each viable technique, demonstrating a very important improvement in the flood mitigation system in Seixal.

Comparing the Cost of Rigid and Flexible Aircraft Pavements Using a Parametric Whole of Life Cost Analysis

The construction and maintenance costs, as well as the residual value, were calculated for structurally equivalent rigid and flexible airfield pavements, for a range of typical commercial aircraft, as well as a range for typical subgrade conditions. Whole of life cost analysis was performed for a range of analysis periods, from 40 years to 100 years. For the standard 40-year analysis period and a residual value based on rigid pavement reconstruction, the rigid pavements had a 40% to 105% higher whole of life cost than equivalent flexible pavements, although this comparison is limited to the pavement compositions and material cost rates adopted. However, longer analysis periods had a significant impact on the relative whole of life cost, although the rigid pavements always had a higher cost than the flexible pavements. The assumed condition of the rigid pavement at the end of the design life was the most influential factor, with a 60-year service life resulting in the rigid pavements having a lower whole of life cost than the flexible pavements, but assuming a requirement for expedient rigid pavement reconstruction resulted in the rigid pavements costing approximately 4–6 times the cost of the flexible pavements over the 40-year analysis period.

Qualitative approach in improving the market penetration and justifying the potential viability of solar water heaters for sanitary water heating in Dimbaza in South Africa

The study focused on the economic life cost analysis of implementing a solar water heater (SWH) in a building with an electric geyser for water heating and the employing of a methodology that account for the market uptake of SWHs. The study involves the performance monitoring of the electrical energy consumed in a residence with first a 200 L, 4 kW geyser and later a 200 L, 2kW SWH. Secondly, the administering of survey questionnaires to 50 residences in Dimbaza on their perception of switching from a geyser to a SWH (based on the monetary saving inserted on the labelled of the product, the sensitization of the target population on the awareness of the SWHs). The findings show that by replacing the geyser with a SWH, the electrical energy saving on hot water heating can be reduced by 40% and the net present value payback period was 4.44 years. The interest of the selected household representatives to switch to SWHs increased from 27 to 42, in the case when only the monetary saving strategy was used and when both the money saving and awareness campaign strategy was adopted. The study can assist both the service providers of solar water heaters and the policy makers in promoting the market penetration of the SWHs. It also justified the economic viability of SWHs. .

Evaluation of Cost Competitiveness of Electric Vehicles in Malaysia Using Life Cycle Cost Analysis Approach

The need to mitigate CO2 emissions from the transportation sector has necessitated the adoption of electric vehicles (EVs) and other forms of alternative vehicles. Despite the global rise of EVs demand as a complementary means of green transportations, the level of adoption in Malaysia is still not encouraging. Therefore, this study aimed to investigate the cost competitiveness of EVs in comparison with Hybrid Electric Vehicles (HEVs) and an Internal Combustion Vehicle (ICV) based on Malaysia scenarios. Using the existing data in Malaysia, life cost analysis (LCC) of two EVs was computed and compared with HEVs and ICVs. The study shows that Nissan leaf and BMW i3s EVs with LCC of $1.75 and $2.5 per km are not cost-competitive based on prevalent data available in Malaysia compared to the HEVs and ICV. Based on the sensitivity analysis, changes in the components of the operating costs significantly influence the accumulated cost of ownership of the EVs whereas the cost of ownership of the HEVs and ICVs did not experience any significant influence. The findings from this study could serve as bases for policymakers to formulate appropriate policies and strategies to improve the competitiveness of EVs in Malaysia.

Comparative assessment of insulated concrete wall technologies and wood-frame walls in residential buildings: a multi-criteria analysis of hygrothermal performance, cost, and environmental footprints

ABSTRACT Utilizing appropriate materials and assemblies in building envelope components could lead to energy savings, increased durability, and sustainability gains. This study aims at providing an integrated assessment framework to compare three different types of exterior wall systems: wood frame, insulated concrete forms (ICFs), and pre-cast insulated concrete panel (PICP). The focus will be on building envelope performance, cost efficiency, and environmental impacts of these technologies. Such an assessment contributes to decisions on design characteristics of exterior walls as well as the selection of required materials. First, the exterior wall technologies will be compared in terms of hygrothermal performance according to ASHREA standards and other relevant literature. Then, a whole life cost analysis is conducted in order to establish the cost profile of each technology in buildings including capital costs as well as space heating costs over their service life. Finally, we will turn to assessing the environmental footprints of each technology and its components through life cycle assessment (LCA). The proposed framework incorporates multiple performance assessment criteria including well-being aspects, hygrothermal performance, life cycle assessment (LCA), and life-cycle cost (LCC). A multiple criteria decision-making framework is proposed to rank the alternative exterior wall technologies for a case study building.

Energy and life cost analysis of a wet wall solar still with various pump working conditions

In this study, a basin type solar still is investigated whose enclosure walls are soaked with a periodic injection. The equipment was tested under the climatic conditions in Semnan, Iran. Two enclosures were manufactured for this purpose. One of them enjoyed a pump to soak the enclosure walls, while the other one was a conventional system with no such pump. In active chamber, effects of pump's working and off durations were investigated before being compared with those of a passive one. The results showed that the efficiency could be enhanced 7% and the rate of output fresh water could be increased ∼75% with the wet walls. © 2016 American Institute of Chemical Engineers Environ Prog, 36: 532–538, 2017

Railway infrastructure asset management: the whole‐system life cost analysis

Delivering the railway infrastructure whose functionality is sustainable and uncompromised in terms of safety and availability under ever decreasing budget constraints is a great challenge. The successful accomplishment of this task relies on the effective management of individual assets within a wider whole system perspective. This is a highly complex decision-making task where mathematical models are required to enable well-informed choices. In this study, a novel modelling framework is proposed for performing the whole system lifecycle cost analysis. The framework is based on two models: railway network performance and costs. Using the former model investigations of the effects of decisions can be carried out for the individual asset and the whole system. A Petri net modelling technique is used to construct the model. A form of Monte Carlo simulation is then used to obtain model results. The infrastructure performance model is then integrated with the cost model to perform the lifecycle cost analysis. A superstructure example is presented to demonstrate the application of the approach. The results show that taking into account interdependencies among the intervention activities greatly influences, not only the performance of the infrastructure, but also its lifecycle costs and thus should be included in the cost analysis.

Intelligent Transport System – RRUKA Special Issue ‐ Editorial

The Rail Research UK Association (RRUKA) was formed in 2010 with the aim of providing a forum in which industry and academia can come together to identify and deliver fundamental research which will benefit the whole railway system. There are currently 51 institutional members and over 300 RRUKA researchers who have the expertise and skills to develop new concepts to address long standing issues and explore emerging opportunities that the industry is keen to exploit. The association fulfils its objectives through a number of activities, including networking events, conferences, thematic workshops, and facilitating the delivery of academic research. This IET Intelligent Transport System Special Issue presents a selection of research papers presented at the third RRUKA annual conference held in London in 2014. The conference showcased the activities of the members, who presented their latest work both in the plenary speaking sessions, and also in the Blue Sky Village where industry and academic colleagues exchanged ideas and concepts for the next generation of cutting edge solutions. Mark Carne, Chief Executive of Network Rail, set out in his keynote to address the challenges facing the railway, and outlined the future vision of an entirely digitally- enabled railway system. In this future vision the railway system will fully embrace and adopt emerging digital technology in all aspects of its operation, delivering benefits for the passenger, operators, maintainers, and renewals and upgrades. The papers published in this issue cover a broad spectrum of research within the scope of ITS. System wide issues are addressed by the papers on: the whole-system life cost analysis method for railway infrastructure management; the geospatial safety risk model; and electromagnetic compatibility between rolling stock and the surrounding systems. Optimisation of the railway system and its operation is tackled in papers which address: the turnaround arrangements at terminal stations; delay management with minimal energy consumption; and the use of remote condition monitoring for improved wheelset management. The paper examining how passengers have dealt with the increased amount of counter-terrorism measures which are now implemented within stations, and also the paper which addressed how the system is coping with an aging passenger population, particular relating to slips trips and falls, provide relevant research into human factors. Some of the most interesting and creditable work that is undertaken by RRUKA members and supported by industry partners is published in this issue. We hope that you find the papers of value. More information on the association and how you can engage can be found on our website www.rruka.org.uk.

Energy Analysis of Roof Integrated Solar Collector for Domestic Heating & Cooling Under Local Conditions of Pakistan

Household utilization of energy represents the 46% of Pakistan total energy. This situation requires that new energy model & alternates of energy should be developed for the household utilization of energy. Solar Energy is one of the best available options for this problem. Many designs of solar roof have been developed in the last half century to utilize solar energy from the roof. The previous designs are feasible but their design is complex and their performance. A model of Roof Integrated Solar collector is designed & fabricated. The dimensions of collector are 5 feet long, 4 feet wide & 0.5 feet height. Experimental readings are taken at various times of the day. The effect of orientation is also studied experimentally. Economic analysis is performed for different scheme of solar collector using linear economical approach. Energy Analysis shows that Roof Integrated Solar collector has a very healthy potential for solar thermal application as it has almost 37 % efficiency. The major loss occurs in solar collector. The life cost analysis shows that the cost of Roof Integrated Solar collector is very economical as compared to electric water heater, gas water heater or solar thermal water heater. Energy distribution analysis shows that 37% energy is transferred to water, 32 % is reflected back & 22 % is transferred to the atmosphere through collector walls & base & the rest of 9% is absorbed by the collector surface.

Farklı dış duvar yapıları için optimum ısı yalıtım kalınlığı tespitinin ekonomik analizi

In the countries which supply big amount of their energy needs by import like Turkey using the energy economically is important. Thermal insulation technologies in buildings are the main method for using energy economically. But choosing the thickness of the insulation material redundant causes high insulation costs. For this reason, an optimum point which provides the highest price in insulation applications is the subject. In this study, different building materials (horizontal perforated brick and gas concrete), and isolated forms of insulation (exterior insulation and insulation sandwich) was a model of a building exterior wall. The study determined that the wall and the heat loss through the life-cost analysis, according to the present calculations (LCCA), the optimum thickness of insulation, energy savings and payback periods were determined.

Industrial applications of natural fibres advanced composites: environmental effects and comparative Life Cycle Analysis

Natural fibres composite materials can have an important role for the planet sustainability. The use of such materials involves the following considerations: complete biodegradability; no toxic agents; no fabrication energy consumption (very low emissions). The purpose of this paper is to evaluate the Life Cost Analysis (LCA) of natural fibres composites for industrial applications, for making a comparison with those relative to steel, aluminium and glass fibres production. The comparison shows all the important advantages that we can obtain by the (partial) substitution of such materials with the new natural fibres composites, depending on the applications.

Cost benefit analysis aspects related to long-life pavements

To provide a totally comprehensive Europe-wide cost benefit analysis for the adoption of long-life pavements (LLPs) is not a straightforward task. This paper proposes a methodology to compare the results of the cost benefit assessment of determinate life pavements with that of LLPs. This approach is relevant but nevertheless raises certain issues such as the determination of residual life. Existing models which are available for the economic evaluation of LLPs are presented but none of them take into account all of the significant parameters, for example, environmental costs. In addition, other parameters may be difficult to assess with sufficient accuracy due to the specific behaviour of LLPs such as the lack of deterioration in the structural layers. An example whole life cost analysis of a part of the UK network suggests the large potential benefits to be obtained from the adoption of the LLP design principles on a heavily trafficked road network even before considering the potential environmental benefits of such an approach.

Whole life cost analysis in concrete bridge tender evaluation

In the UK large sums of money are spent annually on the repair and maintenance of structures. To avoid this problem in future construction, many government and private agencies responsible for asset management have recommended that designers should develop schemes that seek to minimise whole life costs, namely construction plus maintenance costs, rather than just initial construction costs. Currently there is no standard procedure for evaluating tenders in terms of whole life costs and therefore no way of checking that this recommendation is being fully implemented. This paper describes a straightforward model that can be used to assess the whole life costs of concrete bridges exploiting alternative durability options and shows how this model could be incorporated in the tendering process.

Whole life cost analysis in concrete bridge tender evaluation

In the UK large sums of money are spent annually on the repair and maintenance of structures. To avoid this problem in future construction, many government and private agencies responsible for asset management have recommended that designers should develop schemes that seek to minimise whole life costs, namely construction plus maintenance costs, rather than just initial construction costs. Currently there is no standard procedure for evaluating tenders in terms of whole life costs and therefore no way of checking that this recommendation is being fully implemented. This paper describes a straightforward model that can be used to assess the whole life costs of concrete bridges exploiting alternative durability options and shows how this model could be incorporated in the tendering process.