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Metsähakkeen mittausmenetelmät ovat kehittyneet 2010-luvulla tiedonkäsittelykapasiteetin kasvaessa ja erilaisten mittausratkaisujen yleistyessä. Konkreettisia esimerkkejä hankintaketjun alku- ja loppupäistä ovat metsäkuljetuksen yhteydessä tapahtuva kuormainvaakamittaus ja voimalaitoksen polttoainekuljettimella suoritettava hakepatjan jatkuvatoiminen mittaus. Tässä tutkimuksessa analysoitiin röntgentekniikkaan perustuvan jatkuvatoimisen mittauslaitteen tuottamaa aineistoa metsähakkeen kosteudesta ja arvioitiin kosteuden tuntemisen merkitystä hankintaketjun eri vaiheissa sekä taloudelliset että ympäristönäkökulmat huomioiden. Tutkimuksen ensimmäisessä osassa jatkuvatoimisen mittauslaitteen tiedot luokiteltiin ja analysoitiin hankintaketjuista saatujen olosuhdetietojen perusteella. Toisessa osassa tienvarsihaketusjärjestelmää simuloitiin kahdella vaihtoehtoisella hakkuutähteen varastointiin liittyvällä päätösfunktiolla. Tutkimuksen tulosten perusteella useimmat tienvarsihaketukseen perustuvat hankintaketjut onnistuvat polttoaineen laadun parantamisessa palsta- ja tienvarsivarastoinnin aikana. Syksyllä korjatun hakkuutähteen kuivumispotentiaali kuitenkin menetetään usein, jos hakkuutähde varastoidaan tienvarteen hyvin pian hakkuun jälkeen. Tienvarren varastokasan peittämisellä saavutetaan varsin usein tavoiteltu 30-40 %:n toimituskosteus voimalaitoksella. Kuorman sisäiseen kosteusvaihteluun ei varastokasan peittämisellä havaittu olevan vaikutusta. Sen sijaan havaittiin, että isoilta tienvarsivarastoilta toimitetun hakkeen kosteus vaihteli selvästi vähemmän kuin pieniltä varastoilta toimitetuissa kuormissa. Simulointimallinnuksen tuloksista havaittiin, että hankintaketjujen ohjaaminen tienvarsivaraston tiedetyn kosteuden perusteella laskisi hakkeen keskimääräistä toimituskosteutta ja vähentäisi hakkeen kuljetussuoritetta verrattuna nykykäytännön mukaiseen toimintaan. Erot tuloksissa olivat merkittäviä etenkin silloin, kun mallinnuksen olosuhdetietoina käytettiin polttoaineen kuivumisen kannalta hankalien säävuosien tietoja. Tutkimus toteutettiin aikana, jolloin jatkuvatoimisen laitteen mittaustietoa oli vielä varsin vähän saatavilla. Tietoaineisto kuitenkin kasvaa jatkuvasti. Voimalaitoksen saamien suorien hyötyjen lisäksi jatkuvatoimisen mittauksen tuottamalla tiedolla on vielä käyttämätöntä hyödyntämispotentiaalia toimitusorganisaatioille, jotka voivat tietojen avulla kehittää omia polttoainetoimituksiaan myös pienemmille laitoksille, joilla jatkuvatoimista mittausta ei ole. The measurement methods of forest chips have developed during the 2010’s, while data processing capacity has increased and different solutions for biomass measurement have become popular in the supply chain. Crane-scale measurement in forwarders and continuous measurement of chips on the power-plant’s fuel conveyor are concrete examples from both ends of the supply chain. In this study, fuel-moisture data produced by an X-ray based continuous measurement device was analyzed. Furthermore, the importance of awareness of moisture in different parts of the forest-fuel supply chain was evaluated from economic and environmental point of view. In the first part of the study, the measurement data was classified and analyzed according to the fuel suppliers’ supply-chain data. In the second part, a roadside chipping based supply system was simulated with two alternative decision procedures concerning intermediate storing of harvest residues at roadside. The results indicate that most roadside-chipping supply chains succeed in upgrading of fuel quality during the stand-storage and roadside-storage phases. The drying potential of harvest residues is, however, often lost in the autumn if the residues are forwarded to the roadside storage very soon after the harvest. A desired delivery moisture of 30-40% at the power plant is usually achieved when the roadside stacks have been covered during the storage. Covering of stacks did not seem to equalize moisture variation within the truckloads. Instead, the moisture variation was found to be higher in truckloads departed from small roadside storages than the ones departed from large roadside storages. The results of the simulation experiments suggest that utilization of the known roadside-storage moisture in supply-chain management would decrease the average delivery moisture at the power plant and reduce the annual haulage of chip trucks in comparison with the conventional decision procedure. Significant differences between the procedures were found especially when weather data from difficult years (from biomass-drying point of view) were used as background variables. The availability of data from continuous measurement device was limited when this research was carried out. Nevertheless, new data is produced all the time. In addition to the direct benefits in heat and power generation, the fuel suppliers have good opportunities to benefit from the data and develop their own forest-fuel deliveries, also to smaller plants where continuous measurement is not used. Publishers version

Terminals are needed to balance temporal differences of supply and demand over time in the supply chain. In biomass logistics, the need for terminals is the highest when the peak seasons of heating and harvests are short and non-simultaneous. Terminal solutions are casedependent and based on different factors.

The profitability of a biomass terminal can be analysed as an individual cost pool in biomass logistics by static calculations, but they can be also complemented by simulation studies. The dynamic simulation approach accounts for temporal factors, whose impacts on the sizing and resource needs of the terminal can be substantial. They can also have economic reflections on the supply system outside the terminal. This paper presents a simulation model and an experiment simulating operations in a large feed-in terminal with different solutions of biomass deliveries. The results indicate that, in typical Nordic circumstances, biomass terminals based on stemwood processing have relatively high storage size and resource need in the winter and underutilization of terminal space in the remaining seasons. Adjustment of the optimal number of resources for each period of the operational year guarantees the fluency of operations at the terminal without significant delays for inbound and outbound truck deliveries., Proceedings of the 25th European Biomass Conference and Exhibition, 12-15 June 2017, Stockholm, Sweden, pp. 48-51

Dry matter losses can be a remarkable cost factor and emission source in biomass supply for energy and biorefining. Roundwood is not sensitive for dry matter losses and that is why storing along a supply chain and in terminals should be focused on roundwood, if possible. Within harvesting residues and comminuted material, dry matter loss of 1% per month is an appropriate figure to be used in inventory calculations. In worst cases, dry matter losses can be close to 3% per month. The measurement of dry matter losses is challenging and despite of serious efforts, the predicting of losses and their biological and physical processes are not known wellenough.

The natural changes in moisture content of energy wood stockpiles can now be forecasted by models, which are using weather statistics, material characteristics, time and location as an input. Models help energy wood supply companies to manage their material flow and improve the efficiency of their deliveries. Models are done for logging residues and for delimbed energy wood. Some companies have implemented models already and experiences are very positive.

Field studies were conducted to gather information on well-functioning terminals, their machines, logistics and infrastructure. Based on the survey, work studies and cost calculations of different terminal functions, supply costs of woody biomass through terminals were defined. Finally, the most effective terminal supply chains were compared with direct supply chains from forest to plant.

Biomass terminals in Finland and Sweden were surveyed in order to learn what kind of biomass terminals there are in these countries. They were also localised and the main characteristics were compared.