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Various departments at a car manufacturing plant are suffering from regular process outages due to voltage dips. These dips are causing production losses in the Metal Operation, Spray Coating, and Assembly departments that directly affect the productivity of the plant. The cost of those losses is directly related to the profile of the voltage dip (duration and depth). Various options to reduce these costs are investigated, with particular emphasis upon the Spray Coating and Assembly departments. The following conclusions can be drawn: 1. The number and type of dips occurring at the point of connection of the plant is regular. It is similar to what is monitored at other medium voltage stations that have the same grid structure. 2. A detailed analysis of the spray coating process reveals that installing a 'restart on the fly' system on the large conditioning fans substantially reduces the related voltage dip losses. 3. A detailed analysis of the Assembly department shows that there are two main bottlenecks that determine the restart time after a dip (the 'Drive' sub-process and the 'Cockpit', 'Marking', and 'Transport chain' users). These bottlenecks can be removed by installing a Dynamic Voltage Restorer (DVR), which results in a payback time of 1.4 years. * 1 Introduction

Application of multi-criteria decision making to sustainable energy planning-A review S. D. Pohekar , and M. Ramachandran Birla Institute of Technology and Science (BITS), Pilani 333 031, India Received 1 December 2003;  accepted 19 December 2003.  Available online 31 January 2004. Abstract Multi-Criteria Decision Making (MCDM) techniques are gaining popularity in sustainable energy management. The techniques provide solutions to the problems involving conflicting and multiple objectives. Several methods based on weighted averages, priority setting, outranking, fuzzy principles and their combinations are employed for energy planning decisions. A review of more than 90 published papers is presented here to analyze the applicability of various methods discussed. A classification on application areas and the year of application is presented to highlight the trends. It is observed that Analytical Hierarchy Process is the most popular technique followed by outranking techniques PROMETHEE and ELECTRE. Validation of results with multiple methods, development of interactive decision support systems and application of fuzzy methods to tackle uncertainties in the data is observed in the published literature. Author Keywords: Author Keywords: Multi-objective optimization; Multi-criteria decision making; Decision support systems; Sustainable energy planning Article Outline 1. Introduction 2. Overview of multi-criteria decision making (MCDM) methods 2.1. Weighted sum method (WSM) 2.2. Weighted product method (WPM) 2.3. Analytical hierarchy process (AHP) 2.4. Preference ranking organization method for enrichment evaluation (PROMETHEE) 2.5. The elimination and choice translating reality (ELECTRE) 2.6. The technique for order preference by similarity to ideal solutions (TOPSIS) 2.7. Compromise programming (CP) 2.8. Multi-attribute utility theory (MAUT) 3. Multi-criteria decision making applications in energy planning 3.1. Multi-objective optimization 3.2. Decision Suppor

The RTI-developed solar cells were created using low-cost materials and processing techniques that reduce the primary costs of photovoltaic production, including materials, capital infrastructure and energy associated with manufacturing.   Prel...

The Energy Department today announced a new partnership between the Department's Challenge Home program and Passive House Institute US (PHIUS) on a voluntary certification process for homes that are so energy-efficient, they can offset most or al...

A recent study by Logan group at Penn State University also demonstrated similar findings in that the energy contained in hydrogen gas not only can offset the energy used for the desalination process but has surplus that can be used for downstream processing.

Several years ago even the mobile phones were very expensive, not to mention computers and airplane flights.

The example of mobile phones is of little relevance here, because cost reduction is driven by the scaling laws of microelectronics. However, the reducing cost of flights - in a way the ultimate energy application - offer a good benchmark. What will happen to flights though if commodity and energy prices go up in the long run?

Early comprehensive life cycle assessments (LCA's) that compared biofuels with fossil fuels already appeared in the beginning of the eighties. Since then the public, scientific and political interest in biofuels has continuously grown and the number of biofuels and assessed parameters has increased.At the same time, the methodology for this type of assessment has improved with certain aspects of the approach having come up by and by a process which still continues today. Several issues related to the land use currently stand in the centre of expert discussions. Keywords: Environmental assessment; Biofuels; Transport; Land use assessment; Fossil fuels Article Outline 1. Objective, scope and background 2. Procedure 3. Results: comparison of biofuels and fossil fuels 3.1. Biofuels from agriculture compared to fossil fuels and against each other 3.2. Biofuels from residues compared to fossil fuels and against each other 4. Results: land use aspects 5. Conclusions and outlook 5.1. Competing land use 5.2. Competing biomass usages

Sure, regenerative braking - the process that converts the energy typically wasted as heat when slowing down and storing it as electrical power in batteries - is a terrific energy saving solution. Many hybrid cars, such as the Prius, use regenerative braking and it's starting to appear aboard hybrid diesel/electric trains as well. But more efficient still is to maintain your momentum and dispense with a train's need to make stops

IBM and researchers from Harvard University launched a joint effort today to identify more efficient and lower-cost solar cell materials using distributed computing. Leveraging small amounts of computing power from potentially hundreds of thousands of personal computers, this latest addition to the company's World Community Grid platform will process more than 1 million configurations of atoms over the next two years in search of an organic molecule that can be used to make materials for an ultra-efficient plastic photovoltaic cell.

SB375 was a process that involved getting a wide range of issues on the table that included suburban and urban development, climate change, oil dependency, children's health, air quality, and transportation.

According to a study from Clarion University, Pennsylvania, USA each step in the current US process of building and running a nuclear plant, from mining the uranium ores to disposing of the wastes, contributes to greenhouse gas emissions. Indeed, the article states that for nuclear power to be a feasible alternative energy source the entire process would need to be more efficient. This study gives a view on nuclear power which includes long standing ideals. The paper seems to offer an intermediate review on issues around the subject of nuclear, in the wider energy debate.

REGENERATIVE BRAKING is widely practised, but there have to be other trains around to absorb the surplus power being fed back into the catenary or third rail. Processing the output from trains and pushing it back into the local grid is possible with an AC power supply, but very expensive with DC traction. Too often, power produced by traction motors in braking mode ends up heating resistor banks. The elegant alternative is to store the braking energy on the train. This not only avoids the electrical complications of regenerating through the traction power supply network. It reduces the rated power requirement of that network by lopping demand peaks during acceleration, saves energy by reducing losses in the catenary or conductor rail, and by limiting voltage drop it allows substations to be further apart. NiMH batteries have the necessary energy storage density in terms of kWh/kg, and are slightly more expensive, but their life in terms of charge/discharge cycles in no way matches the LRV requirement for 2million cycles over 10 years. Flywheels have been tried but never caught on for several reasons.

The European Commission is currently in the process of dreaming up an offshore wind power action plan and it's put a shout out for anyone with an opinion to come forward.

A new process for using aluminum alloys to generate hydrogen from water could make fuel-cell vehicles more practical,

The ECO2 process is a post-combustion CO2 capture process for conventional power plants. The technology is suitable for retrofit to the existing coal- fired, electric generating fleet as well as for new coal-fired plants.

Geothermal energy is in the dock in Germany, but some scientists are pleading for leniency. A government panel is investigating claims by the geological survey for the state of Rhineland-Palatinate that a geothermal plant triggered a magnitude-2.7 earthquake on 15 August in the town of Landau in the state. If the panel finds against the company that built the plant, Geo X of Landau, it could be shut down. Geothermal plants work by pumping water into hot rocks several kilometres down, forcing small cracks in the rock to expand. Steam escapes through the cracks to the surface, where it drives a turbine, producing clean energy. But critics say the process increases the risk of earthquakes. "Any process that injects pressurised water at depth into rocks will cause them to fracture and possibly trigger earthquakes," says Brian Baptie, an earthquake specialist at the British Geological Society.

The process, Current says, lets a utility more efficiently manage the distribution of electricity by allowing two-way communication between consumers and energy suppliers via the broadband network on the power lines. Based on data they receive from hundreds of homes, utilities can monitor usage and adjust output and pricing in response to demand. Consumers can be rewarded with reduced rates by cutting back on consumption during peak periods. And computerized substations can talk to each other so overloaded circuits hand off electricity to underused ones, helping to prevent blackouts.