FI127804B - Method for transporting biofuel at the right time - Google Patents

Abstract

The invention relates to a method for optimizing the timing of transport and / or use of biofuels. In the process, the moisture content of the biofuel stored in a storage location is measured, one or more properties of the storage location's surroundings are measured, the measurement result of the moisture content and the surrounding environment's property is fed to a mathematical model that estimates the biofuel's energy content and a mathematical model is used to determine the biofuel energy content. Further, the invention relates to a system for optimizing the timing of transport and / or use of biofuel, and a method for optimizing the timing of transport and / or use of biofuel, in which system a mathematical model is created.

Description

METHOD FOR THE TIMELY TRANSPORT OF BIOFUELS

Object of the invention

The invention relates to a method for the timely transport of biofuel.

Background of the Invention

The supply of biofuels, such as logging residues, small trees and strains, has increased significantly as new biofuel-fired power plants are being built. Biofuel is a unique material that is particularly heterogeneous. It is typically not mechanically dried, although it is desirable to use the dry solids content of the harvest time15, but it typically dries in its heaps under the influence of heat (sun) and / or wind. Often the biofuel storage facility is located near the material harvesting area, in the terrain. There are several storage locations and the composition and size of each warehouse varies. The duration of the biofuel supply chain varies from weeks to several years.

Comprehensive management of the biofuel supply chain poses many challenges. The supply chain management and inventory accounting elements of traditional wood (log, pulp) are only partially applicable to the management of the biofuel supply chain. The main differences are the effects of the time of birth, the time and date of storage on the properties of the material in stock. Over time, both desired and undesirable changes typically occur in biofuels. The desired change is, for example, drying of the material. Biofuel properties may also be altered through biological mechanisms such as unwanted decay. However, the so-called fermentation, for example, in the wood chips is not typical for energy wood.

From the point of view of the efficiency of a power plant, the most important characteristic of biofuel is its energy content, for which 35 known methods are available. However, it has proved challenging to know how much energy is stored in each existing one

20115696 prh 08 -02-20199 biofuel storage. It is possible to provide a very general estimate of the amount of energy available from stock biofuel, which is typically based on the average energy content of the product. Typically, for example, it can be assumed that about 1 m ^{3 of} small wood contains about 5 2 MWh of energy. In addition, the energy content of biofuel stores can be corrected computationally, for example, by estimating the potential increase in energy content as a result of dehydration, which in practice increases the amount of energy content by a certain constant amount, such as 10% per year. However, this estimate corresponds to the actual situation typically raised. Usually, biofuel deliveries are tracked and paid for in terms of volume (m ³ ) and / or weight (kg), as well as '' total '' energy (MWh) for each type of product.

Energy content can also be measured, which in practice typically occurs by taking a sample, i.e. a certain amount of the product being measured, and measuring the moisture content of that product. However, this method is laborious and uncertain and typically does not provide an estimate of the energy content of the entire biofuel storage because the sample seldom matches the material distribution and conditions of the entire storage.

With prior art biofuel supply chain management, for example, the effect of long storage on biofuel, regardless of storage conditions, does not affect the value of the biofuel, although the actual quality of biofuel and energy from the biofuel will change during storage. As a result, the value of the purchased product and its characteristics may change during storage in an unpredictable manner.

BRIEF SUMMARY OF THE INVENTION

It is an object of the present invention to provide a novel solution for optimizing the time and / or time of transport of biofuel. One embodiment of the example is intended to provide a solution for evaluating and utilizing the amount of biofuel stored in the biofuel storage to optimize the time of transport and / or use of the biofuel.

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In one embodiment of the invention, it is determined how the additional need for biofuel can be predicted. This involves estimating how much energy is stored in the biofuel storage at each point in time and how much additional energy is needed, for example, to reach the target energy level within a predetermined time period.

A method for optimizing the transport and / or use time of a biofuel according to the invention is set forth in claim 1. The system for optimizing the transport and / or use time of a biofuel according to the invention is set forth in claim 12.

According to a preferred example, the solution of the present invention first simulates the behavior of biofuel during storage, which can be accomplished by creating a mathematical model using a computer program 15. In this case, it is most appropriate to take into account the different conditions which vary from one storage site to another and from biofuel sources.

According to one example, the method of the invention measures previously modeled data by one or more measuring devices, such as variable variables in the immediate vicinity of a biofuel and / or biofuel storage site. Preferably, the solution of the invention for optimizing the time of transport and / or use of the biofuel utilizes off-road technology for performing measurements.

In one example, measurable variables in the immediate vicinity of the biofuel storage site are air temperature and / or air humidity. An example of a biofuel variable factor is the moisture content of the biofuel. According to a preferred example, one or more measuring devices are connected to the biofuel repository and / or its immediate vicinity, which measure both the biofuel humidity and the air humidity and / or temperature from the biofuel repository's immediate vicinity. According to a preferred example, the solution according to the invention optimizes the time of transport and / or use of the biofuel, utilizing spatial information, i.e. conditions related to the location of the biofuel storage.

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The method of optimizing the time of transport and / or use of the biofuel according to the invention preferably comprises at least the following steps:

- Measure the moisture content of the biofuel stored at the storage site.

- Measuring one or more characteristics of the vicinity of the storage site.

- Entering the moisture content measurement and the surrounding property measurement result into a mathematical model for estimating the energy content of the biofuel.

- Perform a mathematical model to determine the energy content of the biofuel.

The invention can achieve several advantages. By means of the invention, the properties of the biofuel storage, such as moisture and environmental properties, can be measured in such a way that it is possible to take into account the measurement results in such a way that the energy content of the biofuel can be estimated at any given time.

Time is a key factor in optimizing the transport and / or use time of a biofuel, as over time the biofuel may be exposed to varying conditions such as humidity, temperature fluctuations, wind effects, etc., which can affect the biofuel's properties. In general, the drier the biofuel material is, the better it is for energy production. Therefore, the time needed to dry the material may become a critical factor in considering the cost effectiveness of the power plant 25. In addition, the purity of the biofuel material is a decisive feature of usability.

In one embodiment of the invention, the information estimated from the measurements of the energy content of the biofuel at that time is used at various stages of the process, most preferably from the moment the biofuel storage is created to the power plant. The invention makes it possible to utilize storage accounting in such a way that the amount of storage, that is, the energy content MWh obtained from the biofuel, is taken into account under changing conditions. The method may utilize one or more mathematical models 35 and / or different optimization methods.

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The method according to the invention can be used to measure and evaluate the energy content of biofuel, which has not been done in the past, since the methods used to determine the energy content of conventional wood (log, pulp) are not suitable for determining the energy content of biofuel material.

With the method of the invention, information on the amount of energy contained in energy stores can be updated, for example, based on actual weather, storage time and time, so that changes in material properties under such conditions can be taken into account.

The method according to the invention enables the optimization of the supply of bioenergy and the operation of the power plant by taking into account the properties and availability of biofuel energy storage facilities. The invention can also make it possible to predict the "storage behavior" of bioenergy so that it can be determined how, for example, the amount of energy from the energy wood will change during storage and when transportation and combustion are worthwhile.

An advantage of the invention is the optimization of the storage time and / or the time of transport of the biofuel and thus the avoidance of the transport and / or burning of the excess amount of water 20 contained in the biofuel. The invention thus makes it possible to transport and / or use bioenergy in a timely manner, i.e. without having to be "stored" in storage, i.e. after the product has dried sufficiently. Nevertheless, the invention makes it possible to ensure that the product is not introduced too early in terms of energy efficiency and / or transport costs, for example, when the moisture content of the product is still unnecessarily high. Thanks to the optimization, it may be possible to produce more energy from the same amount of biofuel as a result of the solution of the invention.

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Description of the drawings

The invention will now be described in more detail with reference to the accompanying drawings, in which Figure 1 schematically illustrates a method for optimizing the transport and / or utilization time of a biofuel, Fig. 2 schematically illustrates a biofuel delivery and / or utilization and Figure 4 illustrates a control device according to a preferred embodiment of the invention.

Detailed Description of the Invention

In this application, the term "biofuel" or "biofuel material" refers to any material of biological origin suitable for use in the production of biofuel or as a boiler fuel. Biofuel is typically virgin material and / or waste material from plants such as trees. In particular, biofuel comprises wood-based materials. forest fuel. Forest fuels include, for example, wood, bark, chips, logging residue from thinning, clearing and harvesting of wood, small trees, stumps, twigs and twigs. In this application, instead of the term '' forest fuel '', 30 terms energy wood are also used, both terms having the same meaning in this application.

As used in this application, the term "non-combustible material" refers to all non-combustible materials in normal combustion boilers, such as 35 metals and mineral materials (e.g., rock, sand, gravel, and clay).

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The term '' biofuel storage facility '' means biofuel stored in a storage site, such as a forest, field, roadside or storage area such as a terminal storage facility.

The term "immediate vicinity of a biofuel storage facility" means an environment within a radius of 2 km, 1,5 km or 1 km of a biofuel storage site, more preferably within a radius of 800 m or 600 m, preferably within 500 m, or within 250 m or 100 m of the biofuel storage, and preferably within a maximum of 70 m of the biofuel storage.

The determination of the energy content in the prior art does not allow the whole supply chain to operate in a cost-effective and / or reliable manner and with sufficient accuracy in the supply of biofuels. Therefore, incorrect data and / or assumptions unnecessarily burden the entire biofuel supply chain. The invention departs from the prior art thinking that substantially the same amount of energy is obtained at the power plant from the same cubic volume of certain timber. Instead, the idea has been changed to better reflect reality.

According to a preferred example, the invention employs one or more predetermined parameter gauges in combination with a predictive mathematical model to estimate the amount of energy contained in a particular biofuel storage at each time point in the modeling. According to one of the 25 preferred examples, at least 50% accuracy in estimating said amount of energy is achieved, and more preferably about 80% accuracy in estimating said amount of energy. It has been found that modeling with up to 50% accuracy represents a significant improvement in current practice by significantly increasing the cost-effectiveness of biofuel procurement. As a result, the process of the invention makes it possible to substantially increase the profitability of the biofuel chain.

The solution according to the invention evaluates the energy content of the biofuel storage at a given time and / or period, which may be present and / or a certain period in the past and / or a certain period in the future. Additionally, one or more biofuel stores are preferably maintained

20115696 prh 08 -02-20199 energy content as a function of time. Estimated energy content of the biofuel storage is used to optimize the time of transport and / or use of the biofuel, such as to determine the optimal time of transportation of the biofuel in a particular biofuel storage and / or 5 optimal use times in the power plant. The measurements according to the invention can be carried out with measuring devices according to the prior art.

In a preferred example, a mathematical model for estimating the true energy content of the biofuel is created. At least the same measurements as in the method for optimizing the time of transport and / or use of biofuel are carried out in the creation of the mathematical model. Thereafter, said mathematical model is used in conjunction with one or more of the measurements included in the model to estimate the true energy content of one or more biofuel stores over time.

Figures 1 and 2 schematically illustrate a system for optimizing the time of transport and / or use of a biofuel according to an embodiment. The figures illustrate how biofuel measurements 2, biofuel location information 3, and / or biofuel 20 near-stock measurements 1 can be used to estimate the energy content of a biofuel over a given time and to use the biofuel optimum and transport time. Figure 2 shows a first gauge 1 for environmental measurements, a second gauge 2 for biofuel measurements, biofuel location information 3, a control system 4 containing a mathematical model block, and information for optimizing biofuel transport and / or time 5 control signal.

Figure 3 shows the energy content curve of an example biofuel as a function of time. In addition, the book value of the prior art relative to the actual energy content is illustrated.

The graph in Figure 3 shows three different concepts of energy content35. Model A typically represents an in-use model that assumes that the energy content of the biofuel stays the same at the time of storage.

20115696 prh 08 -02-20199 until the warehouse is operational. Model B is another commonly used model that attempts to correct Model A's energy content of the biofuel storage by disposing it of a constant factor. This standard change, for example + 10%, can be made, for example, once a year, from the time the inventory is created until the point of use. Model C illustrates a novel solution of the invention that determines the energy content of a warehouse over time based on measurements and a mathematical model.

Fig. 4 shows a control block 40 according to a preferred embodiment of the present invention in a reduced block diagram. The control system 40 preferably comprises a control block 41, such as a processor or the like, whose operation can be controlled by program instructions. The control system further comprises means for receiving data, such as measurement results, 42 for receiving data from, for example, first and / or second measuring devices 1, 2, and memory 43 for storing data. The control system 40 may further include a display 45 for displaying information so that the control system user can monitor, for example, changes in the energy content curve of the biofuel over time, and a keypad 46 for entering information, control commands, etc. into the control system. The data defined in the control block may also be stored, for example, in the control system memory 43, or in the memory of another device (not shown). The control system 40 may further comprise e.g. data transmitting means 44 for forwarding the information defined in the control block to, for example, a power generating plant.

For example, a computer program containing program instructions for controlling the operation of the control system 40 may be used to create and implement the mathematical model of the invention so as to generate the necessary input data from the measurement data, such as said biofuel energy content curve. The computer program, program instructions, and mathematical model 30 may be stored, for example, in control system memory 43. This is represented by block 47 in Figure 4.

According to one example, the method generates a mathematical model using at least the following measurement results:

the moisture content of the biofuel stored at the storage site, at measured times, and

20115696 prh 08 -02-20199 one or more properties of the immediate vicinity of the storage site at the time points measured.

Preferably, the method then feeds to the computer program said moisture content measurement results and said one or more ambient property measurement results to generate a mathematical model for estimating the energy content of the biofuel, and generating a mathematical model for determining the energy content of the biofuel.

In the solution of the invention, to optimize the time of transport and / or use of biofuel, measurements are made such that at least one second measuring device 2 measures at least one property of biofuel in the biofuel storage, preferably the moisture content of the biofuel. In addition, one or more features related to the location of the biofuel storage facility and / or other external features of the biofuel are taken into account. In practice, one or more first and / or second measuring devices 1, 2 can then be attached to the immediate vicinity of the biofuel storage and / or to the biofuel. The second measuring device 2 may be based on one of the following measurement methods: infrared, radiometric, impedance, capacitive, microwave or supercouple magnetic resonance (NMR) measurement. Kos20 can be measured either by chipping a biofuel sample and measuring it from chips, or by measuring moisture directly from the biofuel material.

According to a preferred example, at least one first measuring device 1 per one biofuel storage is used to measure external conditions that may have an effect on the biofuel. These measurements of the immediate vicinity of the biofuel storage facility shall be made at each of the storage sites concerned or in the immediate vicinity. This improves the reliability of the measurements, since external conditions can change substantially due to the shape of the terrain, even in adjacent areas. In other words, the microclimate 30 and its possible changes can be essential factors in estimating the energy content of a biofuel and in creating and / or using a mathematical model for estimating the energy content of the biofuel. In this case, the mathematical model used according to a preferred example takes into account the location and environmental conditions of the biofuel storage facility with sufficient accuracy, which may include, for example, terrain and / or soil type. General, for example, municipal, weather information is typically not

20115696 prh 08 -02-20199 not sufficient when using a mathematical model to optimize the time of transport and / or use of biofuel. Measuring devices may be located in the immediate vicinity of the biofuel storage facility, for example during the biofuel harvesting and / or storage and / or local transportation phase.

According to one example, when estimating the energy content of small-size biofuel stores to optimize the supply of the biofuel store, it may in some cases be cost-effective to determine the energy content of a biofuel store simply by following a mathematical model. 10 Typically, however, for biofuel storage facilities, it is advantageous to use measuring instruments alongside a mathematical model to assure the energy content of the storage.

According to one example, the solution of the invention for optimizing the transport and / or use time of the biofuel includes a control system 40.

According to one example, the measuring device transmits measurement results from a biofuel storage facility or its immediate vicinity, which can also occur to your wireless !, control system 4, 40, whereby data transfer can take place in real time or substantially in real time. In addition or instead of this, the stored data may be transmitted periodically to the control system. The control system 4 then preferably combines one or more measurement results and / or one or more harvest and storage area data (e.g., soil, storage location, time of harvest) and / or one or more weather data and combines said data with the mathematical model used. It is then possible 25 to estimate the energy content of said biofuel storage at that time and / or to predict the evolution of the energy content of said biofuel storage. According to a preferred example, the system for optimizing the transport and / or use time of the biofuel optimizes the best transport time to the power plant or to the so-called terminal depot located near the power plant, per biofuel material storage.

Preferably, the invention utilizes at least one remotely readable measuring device and / or at least one recording first and / or second measuring device 1, 2. The same measuring device 1, 2 can serve as both a recording device and a remote readable measuring device. 35 The transfer of the measurement results from the measuring device to the control system 4, 40 and / or other storage unit may be carried out, for example, several times.

20115696 prh 08 -02-20199 daily, once a day, some times a week, once a week, 1-4 times a month, or less frequently.

According to one example, the method according to the invention uses at least one recording first and / or second measuring device 1,2. The results of the measurements made by the measuring device are then recorded and read and / or transmitted at desired intervals. The recording and / or reading interval of the results of the recording instrument may be up to several months. According to one example, the method of the invention uses at least one remotely readable measuring device 10 which is a recording measuring device. Thus, according to a preferred example, one or more cars, such as a biofuel delivery vehicle, have a reading device for said readable measuring device, wherein, according to a preferred example, the readings measured by the measuring device are arranged

According to one example, the mathematical model used to estimate the energy content of a biofuel storage is updated on the basis of a relatively accurate measurement obtained from a power plant and / or a biofuel 20 material measuring device, such as an energy meter. In this case, the said mathematical model can be subjected to adjustments if necessary.

When assessing and / or predicting the energy content of a biofuel, one or more of the following factors shall be taken into account, as appropriate:

weather information, evaporation, tree growth conditions,

- timing of forest transports, time of harvesting of biofuel, type of harvesting, quality of storage, information on the biofuel storage35 and / or its surroundings measured by one or more measuring instruments 1,2, type of energy,

20115696 prh 08 -02-20199 biofuel type, soil type of harvesting site and / or storage site, geographic location / climatic conditions of the storage site, topography, geographic information available (Geographic Information, Gl), and time of delivery of the biofuel dry, for example, in the felling area when spread (typically drying slows down in a large pile).

These are most appropriately considered for predefined periods of time in the immediate vicinity of the bio10 fuel storage.

For example, weather information includes one or more of the following:

- rainfall,

- humidity,

air temperature, and

- wind speed.

Evaporation is a calculated value influenced by e.g. weather and density of trees at that location.

The growth conditions of wood are influenced by e.g. forest management and other vegetation.

The effect of the timing of forest transportation is based on, for example: storage time. In addition, it is good to consider the surrounding conditions during the storage period.

Biofuel harvesting time refers to e.g. the season and the circumstances surrounding it, such as the weather during that season.

Warehouse quality refers to eg. how efficient the biofuel is. This is influenced by e.g. whether the biofuel storage is covered by rain cover.

Energy types refer to whether the biofuel comprises, for example, logging residue, small wood, stumps, twigs, or some other type of energy. According to one of 35 examples, biofuel comprises material and energy tree strains. In this case, said strains may be pre-crushed and / or crushed before storage

20115696 prh 08 -02-20199 and / or during storage, which is best taken into account when assessing the energy content of the biofuel. Crushing of strains typically affects properties affecting its energy content, such as changes in moisture content, and can also affect the amount of non-combustible material in the strains.

Biofuel types include: the type of wood. For example, a small tree dries differently depending on whether it is spruce, pine, birch, aspen or some other species of wood. When using energy wood, wood species matter because, for example10, the stump of a fir tree is different in energy from that of a pine tree.

Wood species differ, for example, in that the moisture content of different wood species may be different and the drying method of different wood species may also be different.

Information on the soil type or soil type may be available as spatial information. Country15 species include, for example, mineral soils and organic soils. The soil types can be refined with additional attributes that tell how the soil types differ from their basic type. Mineral soil types include quarry and rock, gravel, till, sand, sand, gravel and clay. Organic soils include, for example, silt and mulch, as well as humus, which is a type of mulch or 20 peatlands.

The type of soil can play an important role, for example, in the presence of impurities (non-combustible material) in biofuels, especially in energy wood. If the biofuel harvest is carried out, for example, in finely divided soil with dry air, the soil will be removed, for example, from small trees and branches.

Likewise, when stumps are lifted, the soil is easily detached from the roots. Instead, when executed in fine soil with moist air, non-combustible material is typically trapped in biofuel, such as tree roots. In this case, said non-combustible material can be removed after 30 drying. If biofuel harvesting is carried out on gravelly soil, gravel usually drips out of the biofuel, regardless of moisture. When performing biofuel harvesting in, for example, peatland, there is e.g. in energy terms, the better the amount of peat that is trapped in, for example, the energy tree. Thus, there is no attempt to remove peat from the energy wood.

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Both the mathematical model and the at least one first and / or second measuring device are used to predict the amount of energy in the energy wood. One or more of the above variables is suitably selected for the mathematical model. The mathematical model is most suitably implemented by taking into account the measurement results of both 5 biofuels and the environment. In addition, it is most appropriate to take into account factors which generally do not change significantly over time (during the storage of biofuel), such as information on the location of the biofuel storage, such as soil type and / or landforms and / or geographical location.

The invention makes it possible to optimize the storage time and / or the time and / or the time of use of the biofuel. In other words, the invention can optimize the drying and energy content of the biofuel by delivering the biofuel from storage sites to the power plant at the best possible time and even so that the composition and quality of the biofuel entering the power plant produce the best possible amount of energy. In this case, it is possible to reduce the amount of water contained in the biofuel to be burned and thus obtain more energy from the same amount of biofuel in the power plant, since less energy is needed to heat the water than when using a wetter biofuel. In addition, it is possible to reduce the amount of water transported with the biofuel and thus to reduce the cost of transporting the biofuel.

The invention is not limited to the examples set forth in the figures and in the foregoing description, but may be modified within the scope of the appended claims.

Claims (10)

Claim: 1. Procedure for transporting biofuels at the right time, the procedure first comprising: 5 - Creating a mathematical model to estimate the biofuel energy content using at least the following measurement results: • the moisture content of biofuel stored in a storage location at measurement times, and • one or more properties of the storage environment's proximity, comprising 10 at least one weather task, at measurement times, and which method, in the creation of the mathematical model, comprises - input said results from moisture content measurements and said results from measurements of one or more properties of the surrounding environment in a computer program, to create the mathematical model for estimating the biofuel energy content, and - creation of the mathematical model to determine an estimate of the biofuel energy content, and then - measurement · Of at least one characteristic of the storage location's proximity, comprising at least one weather report, with a first measuring device (1), and • of the moisture content of the biofuel stored in the storage location, with a second measuring device (2), At least one of said first and / or second measuring means (1, 2) is a remote readable measuring device and / or a recording measuring device, - at least the second measuring device (2) of said measuring device is located in the biofuel or in the immediate vicinity of the biofuel storage, the method comprising - measuring the moisture content of the biofuel stored in the storage location, directly from the biofuel material, with the second measuring device (2), and - input the result from the measurement of said one or more properties of the local environment, comprising at least one weather data, in said mathematical model to estimate the biofuel energy. 35, in the computer program, to estimate the energy content of the biofuel, 20115696 prh 08 -02 2019 - further input of the result from the measurement of the moisture content of said mathematical model to estimate the energy content of the biofuel, in the computer program, - optimization of the timing of transport of biofuel with computer- Using the estimated energy content of the biofuel, the method comprising - estimation of the optimal time for the transport of biofuel contained in said biofuel storage location, and the procedure further comprises 10 - transport of biofuel at the right time according to the estimated optimal time of transport. Method according to claim 1, characterized in that said weather information is selected from: 15 - air temperature, - humidity, - wind speed, and - Precipitation. 20 Method according to claim 1 or 2, characterized in that in the said mathematical model the geographical location of the biofuel storage location is also entered. Method according to any of the preceding claims 1-3, characterized in that the method comprises - optimization of the best time for transporting said biofuel to a power plant or so-called. terminal layer. Process according to any of the preceding claims 1-4, characterized in that said biofuel is energy-rich. Process according to any of the preceding claims 1-5, characterized by the transport and / or use of biofuel at the correct time by means of the optimized time. Process according to any of the preceding claims 1-6, characterized by the use of said mathematical model for estimating the energy content of the biofuel as a function of time. 5 Method according to claim 7, characterized by the use of said mathematical model for estimating the energy content of the biofuel for a certain period of time that is in the future. Process according to any of the preceding claims 1-8, characterized by optimizing the timing of transport and / or use of the biofuel using the estimated energy content of the biofuel by minimizing the water content of the biofuel to be burned. Method according to any of the preceding claims 1-9, characterized by updating the mathematical model used to estimate the energy content of the biofuel storage based on measurement results from the power plant and / or the biofuel measuring device.