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In this paper, the concept ‘green approaches’ already used in aviation is applied to cargo transportation at sea. Instead of anchoring outside a port waiting for berth, ships can adjust their speed to arrive just in time for berthing. With improved incentives for reducing speed and shared information about berthing times, green approaches instead of anchoring can be a way to reduce fuel consumption and emissions without increasing the transit times of goods. The present study estimates the benefits to society as a whole for the EU ports in the Baltic Sea with Automatic Identification System data applying a new method using data collected in real time. Data consists of all anchored ships awaiting berth on 40 different occasions in 2015 and are subsequently extrapolated to a year. Fuel consumption by the individual ships, emissions and values are calculated from the detailed data with established models and estimates of unit values. The potential benefits are estimated at 27 million euros per year in the scenario where the near 15,000 anchorings by ships annually awaiting berth may instead start a green approach 12 h prior to arrival and may reduce speed by 25%, using the middle unit values for fuel and emissions. The methodology used in the paper can be applied to estimate the benefits of green approaches in other areas with anchored vessels. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we report the global fuel energy consumption in heavy-duty road vehicles due to friction in engines, transmissions, tires, auxiliary equipment, and brakes. Four categories of vehicle, representing an average of the global fleet of heavy vehicles, were studied: single-unit trucks, truck and trailer combinations, city buses, and coaches. Friction losses in tribocontacts were estimated by drawing upon the literature on prevailing contact mechanics and lubrication mechanisms. Coefficients of friction in the tribocontacts were estimated based on available information in the literature for four cases: (1) the average vehicle in use today, (2) a vehicle with today׳s best commercial tribological technology, (3) a vehicle with today׳s most advanced technology based upon recent research and development, and (4) a vehicle with the best futuristic technology forecasted in the next 12 years. The following conclusions were reached: [•] In heavy duty vehicles, 33% of the fuel energy is used to overcome friction in the engine, transmission, tires, auxiliary equipment, and brakes. The parasitic frictional losses, with braking friction excluded, are 26% of the fuel energy. In total, 34% of the fuel energy is used to move the vehicle. [•] Worldwide, 180,000 million liters of fuel was used in 2012 to overcome friction in heavy duty vehicles. This equals 6.5millionTJ/a; hence, reduction in frictional losses can provide significant benefits in fuel economy. A reduction in friction results in a 2.5 times improvement in fuel economy, as exhaust and cooling losses are reduced as well. [•] Globally a single-unit truck uses on average 1500l of diesel fuel per year to overcome friction losses; a truck and trailer combination, 12,500l; a city bus, 12,700l; and a coach, 7100l. [•] By taking advantage of new technology for friction reduction in heavy duty vehicles, friction losses could be reduced by 14% in the short term (4 to 8 years) and by 37% in the long term (8 to 12 years). In the short term, this would annually equal worldwide savings of 105,000 million euros, 75,000 million liters of diesel fuel, and a CO2 emission reduction of 200 million tones. In the long term, the annual benefit would be 280,000 million euros, 200,000 million liters of fuel, and a CO2 emission reduction of 530 million tonnes. [•] Hybridization and electrification are expected to penetrate only certain niches of the heavy-duty vehicle sector. In the case of city buses and delivery trucks, hybridization can cut fuel consumption by 25% to 30%, but there is little to gain in the case of coaches and long-haul trucks. Downsizing the internal combustion engine and using recuperative braking energy can also reduce friction losses. [•] Electrification is best suited for city buses and delivery trucks. The energy used to overcome friction in electric vehicles is estimated to be less than half of that of conventional diesel vehicles. Potential new remedies to reduce friction in heavy duty vehicles include the use of advanced low-friction coatings and surface texturing technology on sliding, rolling, and reciprocating engine and transmission components, new low-viscosity and low-shear lubricants and additives, and new tire designs that reduce rolling friction. [Copyright &y& Elsevier]

Abstract: This study presents calculations on the global fuel energy consumption used to overcome friction in passenger cars in terms of friction in the engine, transmission, tires, and brakes. Friction in tribocontacts was estimated according to prevailing contact mechanisms such as elastohydrodynamic, hydrodynamic, mixed, and boundary lubrication. Coefficients of friction in the tribocontacts were estimated based on available information in the literature on the average passenger car in use today, a car with today’s advanced commercial tribological technology, a car with today’s best advanced technology based upon recent research and development, and a car with the best technology forecasted in the next 10 years. The following conclusions were reached: [•] In passenger cars, one-third of the fuel energy is used to overcome friction in the engine, transmission, tires, and brakes. The direct frictional losses, with braking friction excluded, are 28% of the fuel energy. In total, 21.5% of the fuel energy is used to move the car. [•] Worldwide, 208,000 million liters of fuel (gasoline and diesel) was used in 2009 to overcome friction in passenger cars. This equals 360 million tonne oil equivalent per year (Mtoe/a) or 7.3millionTJ/a. Reductions in frictional losses will lead to a threefold improvement in fuel economy as it will reduce both the exhaust and cooling losses also at the same ratio. [•] Globally, one passenger car uses on average of 340l of fuel per year to overcome friction, which would cost 510 euros according to the average European gas price in 2011 and corresponds to an average driving distance of 13,000km/a. [•] By taking advantage of new technology for friction reduction in passenger cars, friction losses could be reduced by 18% in the short term (5–10 years) and by 61% in the long term (15–25 years). This would equal worldwide economic savings of 174,000 million euros and 576,000 million euros, respectively; fuel savings of 117,000 million and 385,000 million liters, respectively; and CO2 emission reduction of 290 million and 960 million tonnes, respectively. [•] The friction-related energy losses in an electric car are estimated to be only about half those of an internal combustion passenger car. Potential actions to reduce friction in passenger cars include the use of advanced coatings and surface texturing technology on engine and transmission components, new low-viscosity and low-shear lubricants and additives, and tire designs that reduce rolling friction. [Copyright &y& Elsevier]

Abstract: Calculations on the global energy consumption used to overcome friction in paper machines in terms of friction in motors, transmissions, pumps, blowers, agitators, pipes and the roll systems are presented. The following was concluded: [–] The energy consumed to overcome friction in a paper mill is in the range 15–25%. [–] Globally there were 8525 paper and paperboard machines in operation in 2012. One paper machine uses on an average 140TJ of electrical energy per year. Of this 32% is consumed to overcome friction, 36% is used for the paper production and mass transportation and 32% is other losses. [–] The friction losses in an average paper machine are in total 44.8TJ per year, and they are distributed as 32% due to friction in water-lubricated sliding in seals, doctor blades and fabric/support contacts, 23% due to friction in elastohydrodynamic rolling contacts, 22% due to friction in elastohydrodynamic rolling–sliding contacts, 15% due to friction in oil-lubricated seals and 8% due to friction in hydrodynamically lubricated contacts. [–] Worldwide 105,000GWh electrical power was used in 2009 to overcome friction in paper machines. This equals to 381,000TJ of annual energy consumption. [–] By taking advantage of new technology for friction reduction in paper machines, friction losses could be reduced by 11% in the short term (about 10 years), and by 23.6% in the long term (20–25 years). This would equal to annual worldwide economic savings of 2000 million euros and 4200 million euros; electricity savings of 36,000 and 78,000GWh; and CO2 emission reduction of 10.6 million and 22.7 million tonnes. Potential mechanisms to reduce friction in paper machines include the use of low-friction and highly durable coatings, surface engineering including texturing, low-viscosity and low-shear lubricants and fluids, novel additives, new materials in seals, doctorblades and fabrics, as well as new designs. [Copyright &y& Elsevier]

Segmented coaxial HPGe (High Purity Germanium) detectors have recently been shown to be feasible for Gamma Emission Tomography (GET). This type of detector allows for a combination of high efficiency and high energy resolution in gamma spectrometry of irradiated nuclear fuel. The ultimate aim of developing segmented HPGe for GET measurements is to achieve a high spatial resolution to facilitate imaging of rod-internal features and interrogation of smaller irradiated fuel samples. In this work, we present the optimisation of a segmented HPGe detector through a simulation study using the Monte Carlo particle transport code MCNP. Constraints to each dimension of the detector were identified, from manufacturing limitations and requirements arising from the use of a finite-sized collimator slit. In particular, a relationship between the minimum inner radius of the coaxial detector and the segments azimuthal dimension was derived based on the identified constraints. Segment azimuthal and radial dimensions have been varied (based on the derived relationship between the azimuthal and radial dimension) and the full energy efficiency and misidentification rate were evaluated to obtain the optimal dimensions. The optimal ranges of the segment dimensions were determined. [ABSTRACT FROM AUTHOR]