Tag Archives: transport

596-603 D. Marčev, M. Růžička, M. Lukeš and M. Kotek
Energy consumption of commuting from suburban areas
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Energy consumption of commuting from suburban areas

D. Marčev*, M. Růžička, M. Lukeš and M. Kotek

¹University of Life Sciences Prague, Faculty of Engineering, Department of Vehicles ang ground transport, Kamýcká 129, CZ16521 Prague, Czech Republic; *Correspondence: marcev@tf.czu.cz

Abstract:

The process of suburbanization begun half a century later in the Czech Republic in comparison to Western Europe. It has given rise to similar changes in the individual behaviour of potential residents, resulting in different land use and the emergence of new requirements involving technical and transport infrastructures. Many factors that characterize suburban land use, e.g., density of population (households), free access to public facilities, availability of transport modes, etc., are closely associated with energy consumption, specifically in transport. Suburban development affects not only transportation inside expanding suburban municipalities but also their surroundings, e.g., the cumulative effect of traffic intensity increasing on roads radially oriented towards the city centre has been observed in recent years. The construction of manufacturing facilities, logistic and commercial complexes, entertainment centres, etc. continues within the suburban areas and it tends to significantly increase traffic movements (e.g., in tangential directions towards the core of the city). The current capacity of transport infrastructures does not correspond to the increased vehicle intensity (even not only during peak hours) and it does not guarantee an adequate quality for transport operation. The results of performed traffic surveys proved that morning traffic intensity (during peak hours) on the roads (of 2nd. or 3rd. class) leading to the city centre has doubled in the last five years. These results mean that transport energy consumption has increased enormously. Transport energy consumption is higher than usually expected in these cases. The energy consumption (fuel consumption) determined according to a vehicle’s homologation does not take into account the conditions that may affect driving style in a negative manner, e.g., slow driving, traffic congestions road, vertical alignment and tortuous roads. The mean consumption was 9.2 (l 100 km-1) on the selected trail sections –that is 1.66 more than the combined consumption figure presented by car producers. The selected sections make up 54% of the total trail length. This ‘local consumption’ is linked with higher emission production, details are available below. The author compared specific fuel consumption per 100 km and found that real consumption is evidently always higher than the quantities claimed to be correct by car producers in view of mixed modes. The same has been found by, e.g. Marique & Reiter, 2012 and other authors. The conclusions of the research are potentially relevant and should be used in a spatial planning or decision making processes to prevent ‘urban sprawl’ and the accompanying high energy consumption. Suburban development should go hand in hand with the construction of new transport infrastructures and high-quality public transport.

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529-532 A. Pasila
Changes, challenges and opportunities in the wood energy supply chain
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Changes, challenges and opportunities in the wood energy supply chain

A. Pasila

Seinäjoki University of Applied Sciences, School of Agriculture and Forestry,Ilmajoentie ⁵²⁵, ⁶0⁸00 Ilmajoki, Finland;
e-mail: antti.pasila@seamk.fi

Abstract:

One of the biggest challenges in using bioenergy has been the problem of logistics;that is how, in many cases, to process and transport these low density and bulky raw materials.Finnish  forestry  technology  is  advanced  and  the  same  machinery  which  is  used  in  timberharvesting is often used in energy wood harvesting.A  change  in  the  forest  industry  has  however  caused  some  new  expectations  concerning  thewood  energy  supply  chain.  One  of  the  basic  requirements  for  woodchips  is  low  moisturecontent. In the transportation of wood chips high moisture content, and therefore a high weight,may limit the carrying capacity of vehicles and roads. Also in syngas and charcoal productiondry raw material is needed to be able to control the combustion process.The reduction of moisture content under natural drying conditions means an extended storagetime. With Finnish climate conditions this normally means a storage period of at least one year.The  various  types  of  energy  wood:  stems,  whole  tree  harvested  stems,  logging  residues  orstumps are piled in storage sites and covered. The raw material is chipped or crushed at theseintermediate storage sites and after that transported to bio-refineries.In  the  measurement  of  the  energy  wood’s  quality  and  quantity  there  are  some  differencescompared  to  timber  measurements.  Normally  the  timber  measurements  are  based  on  solidvolume in cubic metres. The forest harvesters are equipped with on-line measurement systems.This  on-line  measurement  is  more  complicated  to  carry  out  in  the  case  of  energy  wood.Especially difficult are the volume measurements in whole tree and stump harvesting. A newmethod used in the measurement of energy wood is weight.

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