Computer-implemented method for controlling a plurality of sites of a distributed energy storage system

Abstract

According to an embodiment, a computer-implemented method (100) for controlling a plurality of sites of a distributed energy storage system, each site comprising at least one battery unit and telecommunication equipment, comprises: providing (101) a mobile virtual network operator service using the telecommunication equipment of the plurality of sites; obtaining (102) criteria for an emergency mode of the mobile virtual network operator service; obtaining (103) abnormal event information; determining (104) a geographical area by comparing the abnormal event information and the criteria for the emergency mode, wherein the abnormal event information fulfils at least one of the criteria for the emergency mode in the determined geographical area; selecting (105) at least one site from the plurality of sites, wherein the at least one selected site is located within the determined geographical area; and activating (106) the emergency mode for the at least one selected site.

Description

COMPUTER- IMPLEMENTED METHOD FOR CONTROLLING A PLURALITY OF SITES OF A DISTRIBUTED ENERGY STORAGE SYSTEMTECHNICAL FIELD

[0001] The present disclosure relates to distributed energy storage systems , and more particularly to a computer-implemented method for managing a plurality of sites of a distributed energy storage system, a computing device , a distributed energy storage system, and a computer program product .BACKGROUND

[0002] A distributed energy storage ( DES ) system can comprise a plurality of sites and each site can comprise at least one battery unit . The DES system can be used for, for example , participating in power grid frequency balancing . For example , when working in national frequency reserve markets , the market operator can require each participant to deliver a selected amount of frequency balancing capacity for the market during the time of resource activation .SUMMARY

[0003] This summary is provided to introduce a selection of concepts in a s implif ied form that are further described below in the detailed description . This sum-mary is not intended to identify key features or essential features of the claimed subj ect matter, nor is it intended to be used to limit the scope of the claimed subj ect matter .

[0004] It is an obj ective to provide a computer-implemented method for managing a plurality of sites of a distributed energy storage system, a computing device , a virtual power plant , and a computer program product . The foregoing and other obj ectives are achieved by the features of the independent claims . Further implementation forms are apparent from the dependent claims , the description and the figures .

[0005] According to a first aspect, a computer-implemented method for controlling a plurality of sites of a distributed energy storage system, each site comprising at least one battery unit and telecommunication equipment , comprises : providing a mobile virtual network operator service using the telecommunication equipment of the plurality of sites ; obtaining criteria for an emergency mode of the mobile virtual network operator service ; obtaining abnormal event information ; determining a geographical area by comparing the abnormal event information and the criteria for the emergency mode , wherein the abnormal event information fulfils at least one of the criteria for the emergency mode in the determined geographical area; selecting at least one site from the plurality of sites , wherein the at least oneselected site is located within the determined geographical area ; and activating the emergency mode for the at least one selected site .

[0006] In an implementation form of the first aspect , the activating the emergency mode for the at least one selected site comprises increasing a charging limit of the at least one battery unit of the at least one selected site .

[0007] In another implementation form of the first aspect , the method further comprises participating in power grid balancing using the plurality of sites and the activating the emergency mode for the at least one selected site comprises decreasing participation of the at least one selected site in the power grid balancing .

[0008] In another implementation form of the first aspect , the abnormal event information comprises weather forecast information .

[0009] In another implementation form of the first aspect , the method further comprises : determining a time range for the emergency mode by comparing the abnormal event information and the criteria for the emergency mode ; and activating the emergency mode for the at least one selected site for the time range .

[0010] In another implementation form of the first aspect , the determining the time range for the emergency mode further comprises : estimating a charging time of the at least one battery unit of the at least one selected site ; and including the charging time in the time range .

[0011] In another implementation form of the first aspect , the estimating the charging time of the at least one battery unit of the at least one selected site comprises : obtaining a target state of charge of the at least one battery unit ; estimating a remaining state of charge of the at least one battery unit ; obtaining a charging power of the at least one battery unit ; and estimating the charging time of the at least one battery unit based on the target state of charge of the at least one battery unit , the remaining state of charge of the at least one battery unit , and the charging power of the at least one battery unit .

[0012] In another implementation form of the first aspect , the remaining state of charge of the at least one battery unit compri ses a remaining state of charge of the at least one battery unit at an end of a power grid frequency balancing period .

[0013] In another implementation form of the first aspect , the criteria for the emergency mode comprises at least one of : a forecasted wind gust speed greater than a wind gust speed threshold; a forecasted continuous wind speed greater than a continuous wind speed threshold; a forecasted snow fall amount greater than a snow fall amount threshold; and / or an estimated impact value of weather on mobile network infrastructure greater than a threshold impact value .

[0014] In another implementation form of the first aspect , the method further comprises participating in power grid balancing using the plurality of sites andthe activating the emergency mode for the at least one selected site comprises adj usting a discharging limit of the at least one battery unit of the at least one selected site .

[0015] In another implementation form of the first aspect , the method further comprises participating in power grid balancing using the plurality of sites and the activating the emergency mode for the at least one selected site comprises selecting a preferred balancing service for power grid balancing for the at least one selected site .

[0016] In another implementation form of the first aspect , the activating the emergency mode for the at least one selected site comprises reducing telecommunication traffic via the telecommunication equipment of the at least one selected site .

[0017] In another implementation form of the first aspect , the mobile virtual network operator service comprises a public protection and disaster relief service .

[0018] According to a second aspect , a computing device compri ses at least one processor and at least one memory including computer program code , the at least one memory and the computer program code being configured to , with the at least one proces sor, cause the computing device to perform the method according to the first aspect .

[0019] According to a third aspect, a distributed energy storage system comprises the computing device according the second aspect and a plurality of sites coupled to a power grid .

[0020] According to a fourth aspect , a computer program product comprises program code configured to perform the method according to the first aspect when the computer program product is executed on a computer .

[0021] Many of the attendant features wil l be more readily appreciated as they become better understood by reference to the following detailed description considered in connection with the accompanying drawings .DESCRIPTION OF THE DRAWINGS

[0022] In the following, example embodiments are described in more detail with reference to the attached figures and drawings , in which :

[0023] Fig . 1 illustrates a flow chart representation of a method according to an embodiment ;

[0024] Fig . 2 illustrates a schematic representation of a site according to an embodiment ;

[0025] Fig . 3 illustrates a schematic representation of battery unit state of charge according to an embodiment ;

[0026] Fig . 4 illustrates a schematic representation of a computing device according to an embodiment ; and

[0027] Fig . 5 illustrates a schematic representation of a distributed energy storage system according to an embodiment .In the following, like reference numerals are used to designate like parts in the accompanying drawings .DETAILED DESCRIPTION

[0028] In the following description, reference is made to the accompanying drawings , which form part of the disclosure , and in which are shown, by way of illustration, specific aspects in which the present disclosure may be placed . It is understood that other aspects may be utilised, and structural or logical changes may be made without departing from the scope of the present disclosure . The following detailed description, therefore , is not to be taken in a limiting sense , as the scope of the present disclosure is defined by the appended claims .

[0029] For instance , it is understood that a disclosure in connection with a described method may also hold true for a corresponding device or system configured to perform the method and vice versa . For example , if a specific method step is described, a corresponding device may include a unit to perform the described method step, even if such unit is not expl icitly described or il lustrated in the f igures . On the other hand, for example , if a specific apparatus is described based on functional units , a corresponding method may include a step performing the described functionality, even ifsuch step is not explicitly described or illustrated in the figures . Further, it is understood that the features of the various example aspects described herein may be combined with each other, unless specifically noted otherwise .

[0030] Fig . 1 illustrates a flow chart representation of a method according to an embodiment .

[0031] According to an embodiment , a computer-implemented method 100 for control ling a plurality of s ites of a distributed energy storage system, each s ite comprising at least one battery unit and telecommunication equipment , comprises : providing 101 a mobile virtual network operator service using the telecommunication equipment of the plurality of sites .

[0032] A mobile virtual network operator (MVNO) can use the MVNO service to provide telecommunication services to users of the MVNO while the MVNO may not operate the physical network infrastructure , such as the plurality of sites and telecommunication equipment in the plurality of sites . The plurality of sites and the telecommunication equipment in the plurality of sites can be operated by a mobile virtual network enabler (MVNE ) .

[0033] Herein, a site may also be referred to as a physical site , a node , a unit , a distributed energy resource , an asset , a battery site , or similar .

[0034] For example , each site or at least some of the sites may be embodied in a base station of a telecommunication network .

[0035] The distributed energy storage ( DES ) system may also be referred to as a virtual power plant (VPP) , a virtual power plant system, or similar .

[0036] The telecommunication equipment may comprise any equipment used for providing the MVNO service . For example, the telecommunication equipment may comprise a computing device comprising at least one processor and at least one memory including computer program code , the at least one memory and the computer program code configured to , with the at least one processor, cause the computing device to provide the MVNO service . The tel ecommunication equipment may further comprise , for example , antennas , digital-to-analog converters , analog- to-digital converters , mixers , filters , amplifiers , modulators / demodulators , detectors , and / or any combination thereof . At least some of these components may be implemented in software and / or hardware .

[0037] The method 100 may further comprise obtaining 102 criteria for an emergency mode of the mobile virtual network operator service .

[0038] The obtaining the criteria for the emergency mode of the MVNO service may comprise , for example , obtaining the criteria from a database or any other data storage , such as memory . The criteria may be implemented as , for example , parameter values . In some embodiments , the criteria may be configured in program code of a computer program and stored in random-access memory (RAM) and / or in a cache memory when the computer program is executing .

[0039] The method 100 may further comprise obtaining103 abnormal event information .

[0040] The abnormal event information may comprise , for example , weather forecast information, information about maintenance work, information about information warfare , information about a security threat , information about heighted risk of blackouts due to cyberattacks , information about hybrid influencing, information about terrorism, and / or any other information that may affect the operation of at least some sites in the plurality of sites .

[0041] An abnormal event may refer to any event that may negatively affect the operation of at least some sites in the plurality of sites .

[0042] For example , weather forecast information may be provided by a commercial weather forecast service or any other party providing weather forecasts . The weather forecast information may comprise , for example , any information relating to weather forecasts , such as forecasted wind speeds , forecasted find gust speed, forecasted rain fall , forecasted snow fall , warnings , etc . Other types of abnormal event information may be provided by various services and / or parties .

[0043] The method 100 may further comprise determining104 a geographical area by comparing the abnormal event information and the criteria for the emergency mode , wherein the abnormal event information fulfils at least one of the criteria for the emergency mode in the determined geographical area .

[0044] The criteria for the emergency mode of the MVNO service may comprise any criteria for the abnormal event information . For example , the one of the criteria may be a wind speed greater than a threshold wind speed and the weather forecast may indicate the wind speed for a speci fic area, such as a country or a state . In such a case , the determined geographical area may comprise all areas where the wind speed forecasted by the weather forecast information is greater than the threshold wind speed .

[0045] The method 100 may further comprise selecting 105 at least one site from the plurality of sites , wherein the at least one selected site is located within the determined geographical area .

[0046] For example , the location of each s ite in the plurality of sites may be stored in a database . By comparing the location of each s ite to the determined geographical area, sites that are within the determined geographical area can be selected . The location of each site may be stored, for example , in the form of an address , coordinates , region, or similar . Each site in the plurality of sites may be associated with a site identifier ( ID) .

[0047] For example , in some embodiments , the weather forecast information may indicate that the weather forecast is applicable to specific geographical regions . In some embodiments , the weather forecast information may be updated and the applicable geographical regions may change .

[0048] In some embodiments , regions can be selected manually from, for example, a dropdown list or a graphical map user interface . The sites in the affected area can be determined based on map and site locations .

[0049] The method 100 may further comprise activating 106 the emergency mode for the at least one selected site .

[0050] In some embodiments , the emergency mode may comprise a plurality of steps / phases . For example , the plurality of steps / phases may comprise a preparation step / phase during which the at least one selected s ite is prepared for the abnormal event . The plurality of steps / phases may further comprise an abnormal event step / phase during which the abnormal event is occurring . For example , the abnormal event information may indicate that extreme weather, during which for example , power may not be available from the power grid, will be affecting geographical areas of the at least one selected site . The preparation step / phase may comprise preparing the at least one selected site for the extreme weather and during the abnormal event step / phase the extreme weather may be occurring .

[0051] Different steps / phases in the plurality of steps / phases may have different time requirements . For example , if the preparation step / phase comprises increasing the state of charge ( SOC) of the at least one battery unit in the at least one selected site , this charging may require some specific amount of time .

[0052] The emergency mode may comprise , for example , any configuration that makes the at least one selected site more robust against the abnormal event , such as adverse weather conditions . For example , the emergency mode may improve the ability of the at least one selected site to operate without power from the power grid .

[0053] The activating the emergency mode may comprise , for example , reconfiguring the operation of the at least one selected site in a manner that makes the at least one selected site more robust against the abnormal event , such as adverse weather conditions . For example , the emergency mode can decrease the power consumption of a site and / or increase the amount of energy stored in the at least one battery unit when adverse weather conditions start . For example , each site may comprise battery capacity to reach, for example , 24 to 36 hours of operation without power from the power grid .

[0054] According to an embodiment , the activating the emergency mode for the at least one selected site comprises increas ing a charging limit of the at least one battery unit of the at least one selected site .

[0055] A charging limit and increasing the charging limit of the at least one battery unit of the at least one selected site can be implemented in various ways . In some embodiments , the charging limit and increasing the charging limit may be implemented directly using the SOC in, for example , percentages . In other embodiments , the charging limit and increasing the charging limit may be implemented via the charging voltage of the at leastone battery unit . The charging voltage of the at least one battery unit may also be referred to as a reference charging voltage or similar .

[0056] The charging limit of the at least one battery unit may indicate a maximum SOC the at least one battery unit should be charged to . The charging limit of the at least one battery unit may be indicated, for example , as a percentage or as a voltage .

[0057] For example , if the at least one battery unit is used for power grid frequency balancing, the SOC may be around 60 - 65% , lowest SOC in practice may be about 40 % and highest 95% during normal operation . For the emergency mode , it can be beneficial to increase the charging limit to , for example 100 % or substantially 100 % , in order to have large amounts of energy available for the site during the emergency mode .

[0058] According to an embodiment , the method further comprises participating in power grid balancing using the plurality of sites and the activating the emergency mode for the at least one selected site comprises decreasing participation of the at least one selected site in the power grid balancing .

[0059] For example , the participating in power grid balancing may comprise performing power grid frequency balancing using the plurality of sites . The decreasing participation of the at least one selected site in the power grid balancing may comprise decreasing participation of the at least one selected site in the power grid frequency balancing .

[0060] According to an embodiment , the method further comprises participating in an energy market using the plurality of sites and the activating the emergency mode for the at least one selected site comprises decreasing participation of the at least one selected site in the energy market . For example , the participating in the energy market may comprise performing intraday trading in the energy market . Intraday trading may be used to help secure the necessary balance between supply and demand in the power grid .

[0061] For example , in some embodiments , in response to receiving abnormal even information for the determined geographical area and time , sites within the determined geographical area are not used for power grind frequency balancing for the time and the at least one battery unit of the sites is fully charged .

[0062] The decreasing participation of the at least one selected site in the power grid balancing may comprise , for example , configuring the at least one selected site not to participate in the power grid balancing . Alternatively, the decreasing participation of the at least one selected site in the power grid balancing may comprise , for example , committing only some part , such as a percentage , of the charge capacity of the at least one battery unit to the power grid balancing .

[0063] The power grid frequency balancing may comprise up regulation and / or down regulation . Up regulation can comprise a site feeding power to the power grid by, forexample , increasing power production of the site and / or decreasing power consumption of the site . Alternatively, the site can be taken off the power grid so that the site does not consume power from the power grid . Down regulation can comprise a site taking power from the power grid by, for example, decreasing power production of the site and / or increasing power consumption of the site .

[0064] For example , during performing power grid frequency balancing, at least some of the plurality of sites can be activated for power grid frequency balancing in response to receiving an activation signal for power grid frequency balancing . For example, a controller of the DES system can receive the activation signal for power grid frequency balancing and transmit control signals to the plurality of sites .

[0065] The activation signal may be provided by, for example , a grid operator . When working in national frequency reserve markets , the grid operator can require each participant to deliver a selected amount of frequency balancing capacity for the market during the time of resource activation . The activated frequency balancing capacity is usually not allowed to fluctuate significantly from its intended setpoint , and the participants can be sanctioned in case the participant is not able to deliver steady frequency balancing capacity for the market .

[0066] Frequency balancing of a power grid may be arranged for example using automatic Frequency RestorationReserve ( aFRR) capacity market . aFRR is a centrali zed automatically activated reserve . Its activation is based on a power change signal calculated on the base of the frequency deviation in a synchroni zed area, such as the Nordic synchroni zed area . Its purpose is to return the frequency of the power grid to the nominal value .

[0067] There is also a new energy market , Picasso , where the activation signal in the aFRR market is based on energy bids , not capacity bids . Capacity bids are used as an incentive to bid energy because once a participant bids capacity they should bid the same amount also in energy .

[0068] Frequency balancing of electric grid may also be arranged using, for example , Frequency Containment Reserve for Normal Operation ( FCR-N) or Frequency Containment Reserve for Disturbances ( FCR-D) that are active power reserves that are automatically controlled based on the frequency deviation . Their purpose is to contain the frequency during normal operation and disturbances . FCR is an active power reserve that is automatically controlled based on the frequency deviation . FCR may be Frequency Containment Reserve for Normal Operation, FCR-N, or Frequency Containment Reserve for Disturbances , FCR-D . Their purpose is to contain the frequency during normal operation and disturbances .

[0069] According to an embodiment , the method further comprises participating in power grid balancing using the plurality of sites and the activating the emergencymode for the at least one selected site comprises adj usting a discharging limit of the at least one battery unit of the at least one selected site .

[0070] The discharging limit may refer to a SOC limit above which a site can be used for power grid balancing and below which site cannot be used for power grid balancing . For example, each site can be configured to not participate in power grid balancing when the SOC of the at least one battery unit is below the discharging limit .

[0071] The adj usting the discharging limit of the at least one battery unit of the at least one selected site may comprise , for example , increasing the discharging limit .

[0072] The adj usting a discharging limit of the at least one battery unit of the at least one selected site can be performed based on, for example , backup reserve and capacity for participation in grid balancing .

[0073] In normal DES operation, a backup SOC limit may be set to , for example , 30 % of maximum SOC of the at least one battery unit so that the at least one battery cannot be discharged below 30 % in normal DES operation . This limit may be due to regulations , for example . The discharging limit may be increased to, for example , 85% during the emergency mode which would prevent usage of the at least one battery unit for power grid balancing below this limit during the emergency mode . Power grid balancing usage would still be possible above the limit and while still providing enough battery capacity tosupport the MVNO service during the emergency mode . For example , the supervisor of the DES system can adj ust the discharging limit to the higher value and the DES system could be used for market participation in the range 85% to 100 % SOC, for example . For example , services like FCR-N which can be semi energy intense could benefit from this .

[0074] According to an embodiment , the method further comprises participating in power grid balancing using the plurality of sites and the activating the emergency mode for the at least one selected site comprises selecting a preferred balancing service for power grid balancing for the at least one selected site .

[0075] A balancing service may refer to, for example, FCR-D, FCR-N, or any other service the DES system can participate in to perform power grid balancing .

[0076] For example , some of the sites can be used for low energy services , such as FCR-D, during normal MVNO service operations . FCR-D up regulation may not significantly affect the MVNO service . In some embodiments , the at least one battery unit can be charged to , for example , around 95% instead of 100 % , during the preparation phase in order to provide FCR-D down regulation services even during the emergency mode .

[0077] Energy capacity forecasting can be done on all sites and the sites that exceed the backup SOC limit requirements significantly can be altered to either have a target SOC or a backup SOC limit or both . I f a sitehas one of such limits, the site may be included in part of the normal DES operations, such as FCR-N or FCR-D.

[0078] When there is an abnormal event, some sites can move for example to the FCR-D pool because the upper 85% increased backup SOC limit is enough energy for e.g. FCR-D. Some site with very limited energy compared to power cannot join the FCR-D pool and must be used for the MVNO service exclusively.

[0079] For example, the backup time of each site in the at least one selected site can be estimated. The backup time can be estimated based on, for example, the total SOC of the site and historical power consumption of the site. The estimated backup time can be compared to a required backup time for MVNO service operations. If the required backup time is reached by a site, the site can be selected for low energy use cases, such as FCR-D. For example, the required backup time may be 24 hours. Thus, if the estimated backup time of a site is 30 hours, the site may be used for low energy use cases.

[0080] A site-specific minimum SOC for the low-energy use case can be calculated. For example, if a site is estimated to provide 30 hours of backup time and only 24 hours is required for MVNO service operations, the minimum SOC can be 90% for the site. Thus, the site can be used for low-energy use cases between 90% and 100% SOC. Such sites can be placed, for example, in a low- energy use case pool, such as an FCR-D pool. Sites that do not reach the required backup time can be placed ina MVNO service pool and may be used only for the MVNO service .

[0081] In some embodiments , in preparation for the emergency mode , such as a day before an expected storm, the market commitment mix of the DES system can be changed towards "flexible commitments" , such as intraday instead of day-ahead trading for procurement optimi zation, FCR-D instead of aFRR as FCR-D has later market commitment time gate , and / or only partial capacity to aFRR capacity market even if in aFRR energy market we can continue to be active . That way the transition from normal operations to the emergency mode can be made more continuous .

[0082] According to an embodiment , the abnormal event information comprises weather forecast information .

[0083] According to an embodiment , the activating the emergency mode for the at least one selected site comprises disabling at least one site load in the at least one selected site . For example, in some embodiments , in case of a grid power outage , all non-critical loads in the at least one selected site may be switched off .

[0084] According to an embodiment the activating the emergency mode for the at least one selected site comprises reducing telecommunication traffic via the telecommunication equipment of the at least one selected site .

[0085] The reducing telecommunication traffic may al so be referred to as throttling or limiting telecommunication traffic .

[0086] For example , the telecommunication traffic via the telecommunication equipment of the at least one selected site can be reduced if the site has been allocated for the MVNO service and there is a grid power outage in the determined geographical area .

[0087] The reducing telecommunication traf fic can be performed on at least two levels . It is possible to reduce the transmiss ion power on the cell level and it is possible to reduce the network traffic . This can require coordination between the DES system and the radio access network (RAN) system .

[0088] The amount of telecommunication traffic can affect the electricity consumption of the s ite by, for example , about 20 % . In exceptional circumstances power supply for the site has can interrupted and reserve power can be used . Data traffic for such a site could be limited using one or more of the following : change the parameters of the s ite radio so that civi l traf fic is transferred to alternative service provided by another base station capable of serving the traffic and / or transfer speeds of data subscriptions remaining at the site can be throttled to a low level . Restrictions can be lifted once the power supply has been restored .

[0089] For example , the reducing telecommunication traffic via the telecommunication equipment of the at least one selected site may comprise determining whether traff ic of each s ite in the at least one selected s ite should be reduced base at least one of : a priority ofthe traffic ; a parameter defining an amount of low priority traffic allowed; and / or a dynamic parameter defining a traffic limiting constant .

[0090] For example , the priority of the traffic can define whether the traf fic is high or low priority . In other embodiments , there may be finer grained categorization of the traff ic priority . For example , high priority traffic may not be limited / throttled while low priority traffic may be limited / throttled . The traffic limiting can be dynamically altered over time .

[0091] The traffic limiting can be stopped, for example , when the abnormal event ends and / or if the sites are signalled to return to normal operations .

[0092] In some cases , it may not be possible to select what site loads are shut down during a power outage since this may be hardwired in the rectifier .

[0093] In some embodiments disclosed herein, some functionality may be disclosed in terms of a three-layer VPP architecture . This architecture is only a non-limiting example and the functionality disclosed herein may also implemented in various other ways and / or using various other architectures .

[0094] A first control layer of the three-layer VPP architecture may be referred to as a planner and may be configured to determine in advance an operating plan for the DES system for a plurality of time slots of a first time period based on aggregated properties of the DES system, wherein the operating plan comprises allocationof aggregated capacity of the DES system for the plurality of time slots , and convey the operating plan to a second control layer .

[0095] The second control layer of the three-layer VPP architecture may be referred to as a supervisor and may be configured to determine rules for selecting sites of the DES system for obtaining the allocated aggregated capacity of the operating plan, monitor operation of the DES system in real time and responsively adj ust the rules ; and convey the rules to the third control layer .

[0096] A third control layer of the three-layer VPP architecture may be referred to as a controller and can be configured to execute selection and activation of individual sites of the VPP system in accordance with the rules .

[0097] According to an embodiment , the mobile virtual network operator service comprises a public protection and disaster relief ( PPDR) service .

[0098] PPDR networks , such as state security networks , have been previously built as entire private networks . State security networks can be used by public protection and disaster recovery officials and by organi zations ensuring the proper functioning of critical infrastructure . For example , repair work on electricity distribution systems can require continuous communication between repair teams and the distribution network operating centre . For example , the Finnish Virve mobile service can be used to provide data and communication service to such organi zations .

[0099] The PPDR operator acting as a MVNO operator while leasing capacity from a commercial mobile network operator can provide cost effective model for producing critical communication services . However, commercial mobile networks can have less cell site overlapping coverage and have a smaller reserve battery capacity on cell sites than a typical state security network . Further, climate change can cause more extreme weather and the power distribution network can be susceptible to power cuts due to , for example, trees or branches falling on the power lines . Short circuits on the power lines can cause sections of the network to be disconnected unti l a repair team has been dispatched and has removed the cause of the short circuit . During heavy storms or severe icing conditions , hundreds of base stations may be out of the main power network and, therefore , a large area may be rendered without mobi le coverage if power is not restored during the window that the on-site reserve power lasts . Repair work and restoring power is a coordinated effort that may involve emergency response power distribution repair teams , mobile operator facilities operating teams , and teams transporting and maintaining portable power generators . The longer the reserve power and the more accurate forecast of the remaining duration, the more effective power restoration work will be and the less the actual unavai labi lity of the mobile network wi ll affect both of ficials and the general population .

[0100] According to an embodiment , the criteria for the emergency mode comprises at least one of : a forecasted wind gust speed greater than a wind gust speed threshold; a forecasted continuous wind speed greater than a continuous wind speed threshold; a forecasted snow fall amount greater than a snow fall amount threshold; and / or an estimated impact value of weather on mobile network infrastructure greater than a threshold impact value .

[0101] For example , the continuous wind speed threshold may be 15 meters per second (m / s ) , 20 m / s , 25 m / s , or 30 m / s .

[0102] For example , the wind gust speed threshold may be 15 m / s , 20 m / s , 25 m / s , or 30 m / s .

[0103] For example , the snow fall amount threshold may be 15 centimetres ( cm) , 20 cm, 25 cm, or 30 cm . The forecasted snow fall amount and / or the snow fall amount threshold may be measured, for example , per hour, per three hours , per six hours , per 12 hours , or per 24 hours .

[0104] In some embodiments , the criteria for the emergency mode may comprise crown snow-load warning and / or thunderstorm warning . Crown snow-load may refer to snow and hard rime that accumulates on tree crowns in cold climates . Crown snow-load may also accumulate onto above-ground power lines and thus affect power distribution .

[0105] In some embodiments , the criteria for the emergency mode may comprise a forecasted crown snow-loadamount greater than a threshold crown snow-load amount. The crown snow-load amount may be measured, for example, as a depth. For example, the threshold crown snow-load amount may be 15 centimetres (cm) , 20 cm, 25 cm, or 30 cm. The forecasted crown snow-load amount and / or the threshold crown snow-load amount may be measured, for example, per hour, per three hours, per six hours, per 12 hours, or per 24 hours.

[0106] In some embodiments, the criteria for the emergency mode may comprise the combination of a forecasted wind gust speed greater than a wind gust speed threshold and power distribution using above-ground cables. In some embodiments, the criteria for the emergency mode may comprise the combination of forecasted continuous wind speed greater than a continuous wind speed threshold and power distribution using above-ground cables. With above-ground cables, high wind speed can be more likely to cause power outages in the sites due to, for example, fallen trees.

[0107] Any of the threshold values disclosed herein can be adjusted to greater values if, for example, the DES system is not used for power grid frequency balancing and the number of sites observing power outages in the power grid is a single region is greater than a threshold number, such as 10.

[0108] Any of the threshold values disclosed herein can be adjusted to smaller values if, for example, the DES system is not used for power grid frequency balancing and the number of sites observing power outages inthe power grid is a single region is greater than a threshold number, such as 10 .

[0109] Adj ustment of the threshold values may be performed, for example , periodically, such as yearly, based on regional analysis of regional power supply statistics or using a statistical analysis of all sites in the DES system to identify sites with a high risk of power outage .

[0110] In some embodiments , the method 100 may further comprise providing a user interface . The user interface may comprise , for example , at least one of : a site power status indicator, a site remaining energy indicator, an indication of which sites are in critical path in view of power outage . The user interface could be used to , for example , prioriti ze and allocate mobile backup power, such as a portable generator, and / or service tickets / actions to restore power .[01 1 1 ] The user interface can be provided, for example , as a part of a cyber security and service operations center (CSOC) or a similar system . Such a system can be used to , for example , monitor the performance of various services , lead troubleshooting and repair measures , and take care of internal and external communication of service disruptions . In some embodiments , such a system can also be one source for providing abnormal event information, such as a high risk of blackouts due to cyberattacks , hybrid influencing, and / or terrorism, and trigger the emergency mode .

[0112] According to an embodiment, the abnormal event information comprises a security threat indication . For example, the security threat indication may be obtained from a user . Sending the security threat indication may require authenticating the user . The security threat indication may indicate which sites and for what time interval the emergency mode should be activated .[01 1 3] According to an embodiment , the method 100 further comprises receiving updated abnormal event information ; determining an updated geographical area by comparing the updated abnormal event information and the criteria for the emergency mode , wherein the updated abnormal event information fulfi ls at least one of the criteria for the emergency mode in the determined updated geographical area ; reselecting at least one site from the plurality of sites , wherein the at least one reselected site is located within the determined updated geographical area ; and activating the emergency mode for the at least one reselected site .

[0114] According to an embodiment , the method 100 further comprises receiving updated weather forecast information ; determining an updated geographical area by comparing the updated weather forecast information and the criteria for the emergency mode , wherein the updated weather forecast fulfils at least one of the criteria for the emergency mode in the determined updated geographical area ; reselecting at least one s ite from the plurality of sites , wherein the at least one reselectedsite is located within the determined updated geographical area ; and activating the emergency mode for the at least one reselected site .[01 1 5] At least some embodiments disclosed herein may improve reliability of MVNO services for, for example , public authorities and / or other critical operators of national security . Especially exceptional situations may cause challenges and outages to PPDR networks . Such challenges should be solved as quickly as poss ible and outages minimi zed .

[0116] At least some embodiments disclosed herein may provide better optimi zation between power grid frequency balancing and emergency preparedness .[01 1 7] At least some embodiments disclosed herein may provide more effective management of power grid restoration work .

[0118] Fig . 2 illustrates a schematic representation of a site according to an embodiment .

[0119] Each site 200 can compri se at least one power source 201 . The power source 201 can be , for example , electrically coupled to the power grid . For example , the at least one power source 201 may comprise a rectifier . Alternatively or additionally, the power source 201 may comprise some other type of power source , such as at least one renewable energy power source . For example , the power source 201 may comprise at least one solar panel , at least one wind turbine , and / or similar .

[0120] In some embodiments , each site 200 in the plurality of sites may comprise a rectifier for chargingthe at least one battery unit 203 using power from the power grid and / or each site 200 in the plurality of sites comprises an inverter 206 for feeding power to the power grid from the at least one battery unit 203 .1 . For example , if the site 200 comprises a direct current ( DC ) system, such as in the embodiment of Fig . 2 , the at least one power source 201 can comprise at least one rectifier for converting the alternating current (AC) to DC compatible with the site 200 . For example , the at least one recti fier can convert 230 -volt AC to 48 -volt DC . In other embodiments , the at least one battery unit 203 may use have higher voltages , such as 350 - 800V, and the rectifier can be used to step up the voltage from the power grid . The at least one power source 201 can be used to drive a site load 202 . The at least one power source 201 can al so be used to provide power to the at least one battery unit 203 .

[0121] In other embodiments , the at least one battery unit 203 may comprise alternatively or additionally, for example, a capacitor, a supercapacitor, and / or similar .

[0122] According to an embodiment , the at least one battery unit comprises at least one battery and / or at least one supercapacitor .

[0123] For example , in the embodiment of Fig . 2 , the at least one battery unit 203 comprises a main battery204 and a secondary battery 205 . The secondary battery205 can be connected, for example , in parallel with the main battery 204 for bi-directional charging . However, the secondary battery 205 and the main battery 204 maynot be connected electrically paral lel in the traditional sense . Rather, the secondary battery 205 may have its own DC-DC converter and the current between the batteries may be AC . When the secondary battery 205 is connected, it can provide additional current to the site 200 on demand to meet the site load 202 or inverter 206 requirements .

[0124] The rectifier can be "partly" used if the terminal voltage of the rectifier is set slightly lower than the battery voltage . In such a configuration, some current is drawn to the site load 202 from the rectifier and some from the at least one battery unit 203 .

[0125] In sites operating on AC, the rectifier may be replaced with another type of component and the site load 202 can operate using AC . However, the at least one battery unit 203 typically operates using DC and the inverter 206 can be used between the at least one battery unit 203 and the site load 202 . Other components , such as DC-DC converters may also be utili zed .

[0126] The at least one battery unit 203 can be used to drive the site load 202 when being controlled to , and to receive charge from the power source 201 during recharge periods .

[0127] The site load 202 can comprise , for example , various equipment consuming power, the type of the equipment can be essentially anything consuming electricity . I f the power source 201 is partly pushing cur-rent to the site load 202 , the frequency balancing capacity for up regulation of the site 200 may not be equal to its power consumption but less .

[0128] For example , the telecommunication equipment may function as the site load 202 . For example , the site 200 may be embodied in a base station of a telecommunication network . The telecommunication equipment may consume power in order to provide the MVNO service and / or other telecommunication services via the base station . The at least one battery unit 203 can be used for power redundancy and / or load shifting of the base station in addition to power grid frequency balancing .

[0129] The site 200 can further comprise at least one inverter 206 that can be electrically coupled to the at least one battery unit 203 and to the power grid . The at least one inverter 206 can be used to feed electricity back to the power grid from the at least one battery unit 203 .

[0130] Fig . 3 illustrates a schematic representation of battery unit state of charge according to an embodiment .

[0131] According to an embodiment , the method 100 further comprises : determining a time range for the emergency mode by comparing the abnormal event information and the criteria for the emergency mode ; and activating the emergency mode for the at least one selected site for the time range .

[0132] The emergency mode may need to be activated only for the time range . For example , the weather at thelocation of a site may cause issues due to , for example , high wind speeds only during the time range . Further, in some embodiments , the time range for the emergency mode may further comprise the time during which the at least one selected site is preparing for the abnormal event .

[0133] The time range for the emergency mode may comprise a plurality of steps / phases if the emergency mode comprises plurality of steps / phases .

[0134] The time range for the emergency mode may also be referred to as a time interval for the emergency mode or similar .

[0135] According to an embodiment , the determining the time range for the emergency mode further comprises : estimating a charging time of the at least one battery unit of the at least one selected site ; and including the charging time in the time range .

[0136] In the embodiment of Fig . 3 , a SOC of the at least one battery unit of a s ite at dif ferent times is illustrated . Based on a current SOC 301 and estimated usage of the site , a remaining SOC 302 can be estimated .

[0137] The charging of the at least one battery unit of the at least one selected site may be a preparation step / phase of the emergency mode .

[0138] According to an embodiment , the estimating the charging time of the at least one battery unit of the at least one selected site comprises : obtaining a target state of charge of the at least one battery unit ; estimating a remaining state of charge of the at least onebattery unit ; obtaining a charging power of the at least one battery unit ; and estimating the charging time of the at least one battery unit based on the target state of charge of the at least one battery unit , the remaining state of charge of the at least one battery unit , and the charging power of the at least one battery unit .

[0139] According to an embodiment , the estimating the charging time of the at least one battery unit of the at least one selected site comprises : obtaining a target state of charge of the at least one battery unit ; estimating a remaining state of charge of the at least one battery unit ; obtaining a maximum charge capacity of the at least one battery unit ; obtaining a charging power of the at least one battery unit ; and estimating the charging time of the at least one battery unit based on the target state of charge of the at least one battery unit , the remaining state of charge of the at least one battery unit , the maximum charge capacity of the at least one battery unit , and the charging power of the at least one battery unit .

[0140] The charging power of the at least one battery unit may be limited by, for example, the charging power the rectifier installed to a site can provide .

[0141] For example , in the embodiment of Fig . 3 , a full SOC target SOC 303 may be needed at the start of the abnormal event . Based on the remaining SOC 302 of the at least one battery unit , the charging power of the at least one battery unit , and the full SOC target SOC 303 , the charging time 304 of the at least one batteryunit can be estimated . The charging time 304 of the at least one battery unit may correspond to a preparation step / phase of the emergency mode .

[0142] Based on the charging time 304 and a proj ected time when the abnormal event is forecasted to reach the site , a latest time by which the charging should start can be estimated .

[0143] The charging time 304 may al so be referred to as a preparation step / phase , since typically the target SOC 303 should be reached before the abnormal event , such as adverse weather conditions , reaches the site . The preparation step / phase may be short if a large rectifier power is available for charging the at least one battery unit . For example , rural sites can have 2 -3 kilowatts of site load consumption and 12 kilowatts of rectifier power . Thus , approximately 10 kilowatts of rectifier power may be usable for charging the at least one battery unit and the preparation step / phase may be 3-4h in practice . On larger sites in suburban areas where the telecommunication equipment is used to provide , for example , many multiple-input and multipleoutput (MIMO) cells and many technologies have been installed, the preparation step / phase can be in the range of 6- 10h .

[0144] In some embodiments , site specific SOC balancing can be performed instead of operating on SOC average of the full DES system .

[0145] In some embodiments , the charging time of the at least one battery unit can be estimated more accurately based on technical characteristics of the DES system . The technical characteristics of the DES system may comprise , for example , the actual battery capacity of the at least one battery unit of a site , which can change over the lifetime of the battery unit , capabilities of the rectifier, the need to heat the at least one battery unit , ambient temperature , and / or temperature of the at least one battery unit .

[0146] With the more accurate estimate of the charging time of the at least one battery unit , the charging time of the at least one battery unit , even from a low SOC, to the required SOC can be optimi zed in order to perform the charging in time for the emergency mode . This can enable , for example , the sites to be used in normal DES operation as long as possible and / or optimi zing charging to optimal hours but sti ll be ready for the emergency mode in time .

[0147] In some embodiments , charging time of the at least one battery unit can be optimi zed and the charging time can be used to determine how low the remaining SOC 302 can be allowed to go whi le the target SOC 303 can still be reached within the available charging time . For example , the target SOC 303 may need to be such that the site has a specified amount of reserve time . This can be performed by taking into account the real ( relatively current ) capacity of the site ( as it changes over time ) , si ze of the rectifier, the temperature of the site , andpossibly the battery temperature . Site specific data can be used .

[0148] After the target SOC 303 has been reached, the at least one selected site may be used for the emergency mode for some time period 306 , such as for time the abnormal event occurs . This may be referred to as the abnormal event step / phase of the emergency mode . At the end of the emergency mode , the SOC 305 of the at least one battery unit may depend on how the at least one battery unit was used during the emergency mode . For example , if a large amount of energy was consumed during the abnormal event , the SOC 305 may be low .

[0149] In the embodiment of Fig . 3 , the total time period 307 of the emergency mode may comprise the preparation step / phase 304 and the abnormal event step / phase 306 .

[0150] According to an embodiment , the remaining state of charge of the at least one battery unit comprises a remaining state of charge of the at least one battery unit at an end of a power grid frequency balancing period .

[0151] Sites may need to be committed to the power grid frequency balancing for specific periods and these commitments may start and end at specific times . For example , the capacity offered to the balancing power market may need to be committed by nine in the morning on the previous day . Thus , for example , in the embodi ment of Fig . 3 , the remaining SOC 302 of the at least one battery unit may be estimated for end of the currentcommit period, since the charging to the target SOC 303 may be started at the end of the commit period . Similarly, after the emergency mode has ended, the selected at least one site may be usable for power grid frequency balancing at the start 308 of the next commit period . Thus , the total time 309 for which the participation of the at least one selected site to the power grid balancing is reduced may be longer than the total time period 307 of the emergency mode .

[0152] According to an embodiment , the method further comprises : determining an updated time range for the emergency mode by comparing the updated abnormal event information and the criteria for the emergency mode ; and activating the emergency mode for the at least one selected site for the updated time range .

[0153] According to an embodiment , the method further comprises : determining an updated time range for the emergency mode by comparing the updated weather forecast information and the criteria for the emergency mode ; and activating the emergency mode for the at least one selected site for the updated time range .

[0154] Fig . 4 illustrates a schematic representation of a computing device according to an embodiment .

[0155] According to an embodiment , a computing device 400 comprises at least one processor 401 and at least one memory 402 including computer program code , the at least one memory 402 and the computer program code configured to , with the at least one processor 401 , cause the computing device 400 to perform the method 100 .

[0156] The computing device 400 may comprise at least one processor 401. The at least one processor 401 may comprise, for example, one or more of various processing devices, such as a co-processor, a microprocessor, a digital signal processor (DSP) , a processing circuitry with or without an accompanying DSP, or various other processing devices including integrated circuits such as, for example, an application specific integrated circuit (ASIC) , a field programmable gate array (FPGA) , a microprocessor unit (MCU) , a hardware accelerator, a special-purpose computer chip, or the like.

[0157] The computing device 400 may further comprise a memory 402. The memory 402 may be configured to store, for example, computer programs and the like. The memory 402 may comprise one or more volatile memory devices, one or more non-volatile memory devices, and / or a combination of one or more volatile memory devices and nonvolatile memory devices. For example, the memory 402 may be embodied as magnetic storage devices (such as hard disk drives, magnetic tapes, etc.) , optical magnetic storage devices, and semiconductor memories (such as mask ROM, PROM (programmable ROM) , EPROM (erasable PROM) , flash ROM, RAM (random access memory) , etc.) .

[0158] The computing device 400 may further comprise other components not illustrated in the embodiment of Fig. 4. The computing device 400 may comprise, for example, an input / output bus for connecting the computing device 400 to other devices.

[0159] When the computing device 400 is configured to implement some functionality, some component and / or components of the computing device 400 , such as the at least one processor 401 and / or the memory 402 , may be configured to implement this functionality . Furthermore , when the at least one processor 401 is configured to implement some functionality, this functionality may be implemented using program code comprised, for example , in the memory .

[0160] The computing device 400 may be implemented at least partially using, for example , a computer, some other computing device , or similar .

[0161] Fig . 5 illustrates a schematic representation of a distributed energy storage system according to an embodiment .

[0162] According to an embodiment , a distributed energy storage system 500 comprises the computing device 400 and a plurality of sites 200 coupled to a power grid 501 .

[0163] Each site 200 in the plurality of sites may be electrically coupled to the power grid 501 . For example , each site 200 may feed power to the power grid 501 and / or take power from the power grid 501 .

[0164] Each site 200 in the plurality of sites may be coupled to the computing device 400 . Each site 200 in the plurality of sites may be communicatively coupled to the computing device 400 . For example , each site 200 may be configured to communicate with the computing device 400 via the internet or any other telecommunicationnetwork . The computing device 400 may be conf igured to control each site 200 in the plurality of sites according to the method 100 .

[0165] The computing device 400 may be communicatively coupled to information sources 502 . For example , the computing device 400 may be configured to communicate with the information sources 502 via the internet or any other telecommunication network . The information sources 502 may provide , for example , the abnormal event information to the computing device 400 . The information sources 502 may further comprise other information to the computing device 400 , such as locations of sites , electricity priding information, power grid frequency balancing information, information on special operations to be performed in the sites etc .

[0166] Each site 200 in the plurality of sites may be located at a different geographical location .

[0167] Any range or device value given herein may be extended or altered without losing the effect sought . Also any embodiment may be combined with another embodiment unless explicitly disallowed .

[0168] Although the subj ect matter has been described in language specific to structural features and / or acts , it is to be understood that the subj ect matter defined in the appended claims is not necessarily limited to the specific features or acts described above . Rather, the specific features and acts described above are disclosedas examples of implementing the claims and other equivalent features and acts are intended to be within the scope of the claims .

[0169] It will be understood that the benefits and advantages described above may relate to one embodiment or may relate to several embodiments . The embodiments are not limited to those that solve any or all of the stated problems or those that have any or all of the stated benefits and advantages . It wil l further be understood that reference to ' an ' item may refer to one or more of those items .

[0170] The steps of the methods described herein may be carried out in any suitable order, or simultaneously where appropriate . Additionally, individual blocks may be deleted from any of the methods without departing from the spirit and scope of the subj ect matter described herein . Aspects of any of the embodiments described above may be combined with aspects of any of the other embodiments described to form further embodiments without losing the effect sought .

[0171] The term ' comprising ' is used herein to mean including the method, blocks or elements identified, but that such blocks or elements do not comprise an exclusive list and a method or apparatus may contain additional blocks or elements .

[0172] It will be understood that the above description is given by way of example only and that various modif ications may be made by those ski lled in the art . The above specification, examples and data provide acomplete description of the structure and use of exemplary embodiments . Although various embodiments have been described above with a certain degree of particularity, or with reference to one or more individual embodiments , those skilled in the art could make numerous alterations to the disclosed embodiments without departing from the spirit or scope of this specification .

Claims

CLAIMS :

1. A computer-implemented method (100) for controlling a plurality of sites of a distributed energy storage system, each site comprising at least one battery unit and telecommunication equipment, the method comprising : providing (101) a mobile virtual network operator service using the telecommunication equipment of the plurality of sites; obtaining (102) criteria for an emergency mode of the mobile virtual network operator service; obtaining (103) abnormal event information; determining (104) a geographical area by comparing the abnormal event information and the criteria for the emergency mode, wherein the abnormal event information fulfils at least one of the criteria for the emergency mode in the determined geographical area; selecting (105) at least one site from the plurality of sites, wherein the at least one selected site is located within the determined geographical area; and activating (106) the emergency mode for the at least one selected site.

2. The computer-implemented method (100) according to claim 1, wherein the activating (106) the emergency mode for the at least one selected site comprises increasing a charging limit of the at least one battery unit of the at least one selected site.3 . The computer-implement method ( 100 ) according to claim 1 or claim 2 , wherein the method further comprises participating in power grid balancing using the plurality of sites and the activating the emergency mode for the at least one selected site comprises decreasing participation of the at least one selected site in the power grid balancing .4 . The computer-implement method ( 100 ) according to any preceding claim, wherein the abnormal event information comprises weather forecast information .5 . The computer-implemented method ( 100 ) according to any preceding claim, wherein the method further comprises : determining a time range for the emergency mode by comparing the abnormal event information and the criteria for the emergency mode ; and activating the emergency mode for the at least one selected site for the time range .6 . The computer-implemented method ( 100 ) according to claim 5 , wherein the determining the time range for the emergency mode further comprises : estimating a charging time of the at least one battery unit of the at least one selected site ; and including the charging time in the time range .7 . The computer-implemented method ( 100 ) according to claim 6 , wherein the estimating the charging time of the at least one battery unit of the at least one selected site comprises : obtaining a target state of charge of the at least one battery unit ; estimating a remaining state of charge of the at least one battery unit ; obtaining a charging power of the at least one battery unit ; and estimating the charging time of the at least one battery unit based on the target state of charge of the at least one battery unit , the remaining state of charge of the at least one battery unit , and the charging power of the at least one battery unit .8 . The computer-implemented method ( 100 ) according to claim 7 , wherein the remaining state of charge of the at least one battery unit comprises a remaining state of charge of the at least one battery unit at an end of a power grid frequency balancing period .9 . The computer-implemented method ( 100 ) according to any preceding claim, wherein the criteria for the emergency mode comprises at least one of : a forecasted wind gust speed greater than a wind gust speed threshold; a forecasted continuous wind speed greater than a continuous wind speed threshold;a forecasted snow fall amount greater than a snow fall amount threshold; and / or an estimated impact value of weather on mobile network infrastructure greater than a threshold impact value .10 . The computer-implemented method ( 100 ) according to any preceding claim, wherein the method further comprises participating in power grid balancing using the plurality of sites and the activating the emergency mode for the at least one selected site comprises adj usting a discharging limit of the at least one battery unit of the at least one selected site .11 . The computer-implemented method ( 100 ) according to any preceding claim, wherein the method further comprises participating in power grid balancing using the plurality of sites and the activating the emergency mode for the at least one selected site comprises selecting a preferred balancing service for power grid balancing for the at least one selected site .12 . The computer-implemented method ( 100 ) according to any preceding claim, wherein the activating the emergency mode for the at least one selected site comprises reducing telecommunication traffic via the telecommunication equipment of the at least one selected site .

13. The computer-implemented method (100) according to any preceding claim, wherein the mobile virtual network operator service comprises a public protection and disaster relief service.

14. A computing device (400) comprising at least one processor (401) and at least one memory (402) including computer program code, the at least one memory (402) and the computer program code configured to, with the at least one processor (401) , cause the computing device (400) to perform the method (100) according to any preceding claim.

15. A distributed energy storage system (500) comprising the computing device (400) according to claim 14 and a plurality of sites (200) coupled to a power grid (501) .

16. A computer program product comprising program code configured to perform the method (100) according to any of claims 1 - 13 when the computer program product is executed on a computer.

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