GB2588260A

GB2588260A - Controlling energy flow within a subnetwork

Info

Publication number: GB2588260A
Application number: GB2005230.4A
Authority: GB
Inventors: Tomlinson Clive; Price Anthony; Mutch David
Original assignee: SWANBARTON Ltd
Current assignee: SWANBARTON Ltd
Priority date: 2020-04-08
Filing date: 2020-04-08
Publication date: 2021-04-21
Anticipated expiration: 2040-04-08
Also published as: GB202005230D0; GB2588260B

Abstract

Optimising the transfer of energy within a subnetwork having an input/output 100 in order to reduce the demand placed on existing transformers and/or substations. Flexible generation and/or consumption equipment 400 may be called upon to consume/generate in response to demand, but only after reconciliation of the inflexible generation/consumption 300; in this way, the flexible equipment may not artificially affect the energy balance by encouraging unnecessary demand. Reconciliation of flexible generation/consumption is performed later, after reconciliation of the inflexible generation/consumption. Energy monitors 200 associated with each generator/consumer produce equipment energy data for a first time period and at a portion of this is matched with a source/sink selected from the other energy monitors based on the equipment energy data.

Description

CONTROLLING ENERGY FLOW WITHIN A SUBNETWORK

The present invention relates generally to a method of controlling energy flow within a subnetwork and finds particular, although not exclusive, utility in controlling electrical energy flow within a low voltage subnetwork, more particularly in an electrical network isolated by a transformer and/or substation handling a power of below approximately 5MW. It is envisioned that the present invention may be applied to flow of other fuels, consumables or other products.

In conventional centralised grid topologies, long-distance flows of electrical energy from generation sites to end users lose a substantial amount of energy as heat.

Historically, this has been accepted in the field. 'I. o minimise this, power is transferred long distances at high voltage, and is stepped down to lower voltages on reaching an end user. In particular, in urban areas, electricity transformers/substations may be found spaced apart by approximately 500m, with each transformer/substation supplying power to a group of end users via low voltage feeders or low voltage feeder cables.

The amount of energy generation and energy storage equipment connected to centralised grids by end users is expected to increase in the future. Energy generation equipment may include fuel cells, wind, solar, or other energy sources that include renewable energy generation devices. Energy storage equipment may include electrical storage systems, dedicated battery systems, electric car batteries and refrigeration and heating systems, including water heating systems, refrigerators and freezers. In addition, there is expected to be an increase in electrical demand in the Sure, due to increased reliance on electrical equipment (for example, by the introduction of heat pumps into home heating systems).

Electricity transformers and/or substations, and low voltage feeders and/or feeder cables, have only limited capacity that may not be enough for increased energy flows due to the additional equipment. For instance, this may be due to electric heating of various components. T Tistorically, as demand grew, these components were replaced and/or upgraded to cope.

In addition, electricity transformers and/or substations are not designed for reverse energy flow due to electricity generation by an end user. The rising trend for home generation may cause damage to such transformers/substations, which may prove very costly to replace.

The present invention may seek to optimise the transfer of energy within a subnetwork in order to reduce the demand placed on existing transformers, substations and/or transmission cables.

According to a first aspect of the present invention there is provided a method of controlling energy flow within a subnetwork, the subnetwork having an input/output (100), the method comprising the steps of: providing a plurality (N) of energy monitors (200), each energy monitor (i of N) associated with at least one respective piece of energy consumption and/or generation equipment (300) in the subnetwork; providing at least one (P) piece of flexible energy consumption and/or generation equipment (400), the or each (j of P) piece of flexible energy consumption and/or generation equipment (400) associated with one (i of N) of the plurality (N) of energy monitors (200) and/or at least one (k of Q) further energy monitor (500); allocating a first amount (Eji Alit) of consumed/generated energy for a first time period (t) of at least one of the plurality of energy monitors (i of N) to the at least one (P) piece of flexible energy consumption and/or generation equipment; the at least one (P) piece of flexible energy consumption and/or generation equipment consuming and/or generating energy in response to the allocation of consumed/generated energy for the first time period (t) by the at least one of the plurality of energy monitors (i of N); each energy monitor (i of N) monitoring energy consumption and/or generation by the at least one respective piece of energy consumption and/or generation equipment during the first time period (t) to produce respective equipment energy data (F,,,) for the first time period (t); and matching a portion (At) of consumed/generated energy during the first time period (t) of each energy monitor (i of N) with a source/sink selected from the plurality (N) of other energy monitors, based on the respective equipment energy data (Ei,t) for the first time period (f) from each energy monitor (i).

in this way, reconciliation of inflexible generation/consumption may be performed after each time period. Flexible generation and/or consumption equipment may be called upon to consume/generate in response to demand, but only after reconciliation of the inflexible generation/consumption; in this way, the flexible equipment may not artificially affect the energy balance by encouraging unnecessary demand. Reconciliation of flexible generation/consumption is performed later, after reconciliation of the inflexible generation/consumption.

The method allows for monitoring of energy consumption and/or generation, prediction of future consumption and/or generation requirements and selection of a source/sink accordingly. In this way, flow of energy within the subnetwork may be arranged to minimise and/or avoid passage through the input/output of the network. In particular, management of flexible energy consumption and/or generation equipment may be incentivised to minimise and/or avoid passage through the input/output of the network.

For example, in a prior time period (t-1): each (i) of the plurality (N) of energy monitors monitoring the energy generated/consumed (Ei,,,) by the at least one respective piece of energy consumption and/or generation equipment associated therewith; matching a portion (1\1;,,A) of consumed/generated energy of each energy monitor (i of N) with a source/sink selected from the plurality (N) of other energy monitors, based on the respective monitored energy (Fli,t_i) from each energy monitor (i); that is, Mi,t_1 assigning any unmatched consumed/generated energy (D1s_1 = -of each energy monitor (i of N) with the input/output of the subnetwork; forecasting energy consumption and/or generation E1 (and optionally also.1131,t and therefore 15 i,t) by the energy consumption and/or generation equipment during the next time period (t); in particular, a persistence model may be assumed in which etc., or at least approximately so, because the time periods may be relatively short compared with typical rates of fluctuation in generation and 25 consumption; in any event, predicting/forecasting a surplus of energy consumed/generated * -M * (=E. -M.

t,t t,t in the persistence model) in that next time period (t); and allocating the predicted/forecast surplus Dix to a plurality of pieces of flexible energy consumption and/or generation equipment (P), such that the predicted/forecast surplus for a single monitor (i) equals the sum over all such flexible pieces of equipment Ej Then, for example, in that next time period (t): each (i) of the plurality (N) of energy monitors monitoring the energy generated/consumed (-E4,,) by the at least one respective piece of energy consumption and generation equipment associated therewith; optionally determining the energy consumed/generated by the flexible pieces of equipment allocated by the energy monitors (i) in the prior time period (t-1) as E j which in an ideal circumstance would equal that allocated (= Ej kj,t), but it is appreciated that this may not be achievable in all cases, such as where the flexible equipment is a solar cell, wind turbine, and/or preferably gas electricity generation, diesel electricity generation, hydro-electric generation/consumption, industrial loads, refrigeration, heating, electrochemical cells, batteries and/or other storage technologies, etc.; matching a portion (MO of consumed/generated energy of each energy monitor (i of N) with a source/sink selected from the plurality (N) of other energy monitors, based on the respective monitored energy TO from each energy monitor (i); that is, Mi,t -E j Fijs (or Mis 5 E -E assigning any unmatched consumed/generated energy (Dix = E -M -E./ Fij s, or Dix = Eis -Mis -E j Aux, as appropriate) of each energy monitor (i of N) with the input/output of the subnetwork; forecasting energy consumption and/or generation Ets+1 (and optionally also Ai1,t+1 and therefore D1s+1) by the energy consumption and/or generation equipment during the subsequent time period (t+1); again, a persistence model may be assumed in which Ei,t+1=E1s, M1,+ etc., or at least approximately so; in any event, predicting/forecasting a surplus of energy consumed/generated E is in the persistence model) in that subsequent time period (t+ 1); and allocating the predicted/forecast surplus il1,j+1 to a plurality of pieces of flexible energy consumption and/or generation equipment (P), such that the predicted/forecast surplus for a single monitor (i) equals the sum over all such flexible pieces of equipment Ej Aij,t+i)* For the subsequent time period (t+1), the principles set out for the 'next' tine period (t) may be applied again.

Matching a portion (Mi) of consumed/generated energy during the first time period (0 of each energy monitor (i of N) may comprise deducting the consumed/generated energy for the first time period (t) allocated to the at least one (P) piece of flexible energy consumption and/or generation equipment, and matching at most the remainder with a source/sink selected from the plurality (N) of other energy monitors, based on the respective equipment energy data (EL) for the first time period (t) from each energy monitor (i) (i.e. Mitt Ect -E j Ft./it or E That is, the consumed/generated energy during the first time period (f) of each energy monitor (i of N), less the flexible equipment's consumed/generated energy Ei Fitt (or where no determination is performed the allocated energy E The equipment may comprise energy generation equipment (including renewable energy generation equipment), energy consumption equipment, and/or energy storage equipment including electrochemical cells, heat storage, pressure storage, water gravitational potential storage, etc., and/or assets the use of which are not time critical, such as heating, refrigeration, cooling equipment, etc. The method may further comprise the steps of: prior to allocating the first amount, making a first forecast of energy consumption and/or generation by the at least one respective piece of energy consumption and/or generation equipment of each energy monitor (i of N) during a first time period (t); wherein allocating the first amount (E jAij,j) of consumed/generated energy for a first time period (t) of at least one of the plurality of energy monitors (i of N) to the at least one (P) piece of flexible energy consumption and/or generation equipment is in response to the first forecast.

The method may further comprise the steps of: making a second forecast of energy consumption and/or generation by the at least one respective piece of energy consumption and/or generation equipment of each energy monitor (i of N) during a second time period (t+1); and allocating a second amount (j A+1) consumed/generated energy for a second time period (t+1) of at least one of the plurality of energy monitors (i or N) to the at least one (P) piece of flexible energy consumption and/or generation equipment, in response to the second forecast The first and/or second forecast may be attained by any conceivable method, for example a persistence method, an averaging method, a trend method, etc. The forecast method may take account of an immediately prior reading and/or additional previous readings. Optionally, the forecast method may also take account of other data, such as weather forecasts, time of day trends on energy usage, etc. The second amount may be less than or equal to unmatched consumed/generated energy (T),,,5E,,,-1\1),) during the first time period (t) of the at least one of the plurality of energy monitors Et of N) The method may further comprise the steps of: each energy monitor (i of N) monitoring energy consumption and/or generation by the at least one respective piece of energy consumption and/or generation equipment during an earlier time period (t-1) to produce respective equipment energy data (Eiji) for the earlier time period (t-1); and matching a portion (AT of consumed/generated energy during the earlier time period (t-1) of each energy monitor (i of N) with a source/sink selected from the plurality (N) of other energy monitors, based on the respective equipment energy data (E,i,,H) for the earlier time period (t-1) from each energy monitor (i) Lie. Mi,t_j wherein the first amount is less than or equal to unmatched consumed/generated energy (E j 1) during the earlier time period (t-1) of the at least one of the plurality of energy monitors (i of N).

The method may further comprise the step of: the plurality (N) of energy monitors sharing the equipment energy data (F.1,,1) th each other.

For example, for the earlier time period (t-1); however, other time periods are also envisaged. In this way, the energy monitors may be able to base the matching, allocation and/or assigning on a more complete set of date. Some or all of the monitors may perform the sharing.

Alternatively or additionally, the sharing may be between the monitor(s) and a management device, such as a server (physical and/or cloud based). In this way, the matching, allocation and/or assigning may be performed centrally in order to optimise such matches, allocations and/or assignments.

Alternatively none of the monitors may perforn any sharing. In this way. the system will be more secure.

The method may further comprising the steps of: the or each (j of P) of the energy monitors and/or further energy monitors associated with the at least one (10 piece of flexible energy consumption and/or generation equipment monitoring energy consumption and/or generation by the at least one (P) piece of flexible energy consumption and/or generation equipment during the first time period (t) to produce respective flexible equipment energy data (Fii4) for the first time period (t); and determining whether the total energy consumption and/or generation by the at least one (P) piece of energy consumption and/or generation equipment during the first time period (t) equals the allocated consumed/generated energy for the first time period (Ej Futt = Ditt-1)* in this way, reconciliation of energy generation/consumption by the flexible assets/equipment may be performed on the basis of actual generation/consumption rather than merely requested generation consumption.

The method may further comprising the step of: the plurality (N) of energy monitors and/or at least one (Q) further energy monitors sharing the equipment energy data (Fii) and the flexible equipment energy data (Fit') with each other.

For example for the first time period (t), similar to the manner discussed above.

The method may further comprising the step of: assigning any unmatched consumed/generated energy (Di,,t =Ei,t-M,,t) during the earlier time period (t-1) of each energy monitor (i of N) with the input/output of the subnetwork.

The method may further comprising the step of: assigning any unmatched and unallocated consumed/generated energy (Di,t = ELt -Mt, -j FiLt or E j Aye) during the first time period (t) of each energy monitor (i of N) with the input/ output of the subnetwork.

in this way, energy reconciliation may be complete.

According to a second aspect of the present invention, there is provided a system for controlling energy flow within a subnetwork having an input/output, the system comprising: a plurality (N) of energy monitors, each energy monitor (i of N) associated with at least one respective piece of energy consumption and/or generation equipment in the subnetwork, each energy monitor (i of N) monitoring energy consumption and/or generation by the at least one respective piece of energy consumption and/or generation equipment during a first time period (t) to produce respective equipment energy data (Et) for the first time period (t); at least one (P) piece of flexible energy consumption and/or generation equipment, the or each (j of P) piece of flexible energy consumption and/or generation equipment associated with one of the plurality (N) of energy monitors or at least one (Qj further energy monitor; and a controller configured to allocate a first amount (Et A ii,t) of consumed/generated energy for the first time period (t) of at least one of the plurality of energy monitors (i of N) to the at least one (13) piece of flexible energy consumption and/or generation equipment; wherein: the at least one (P) piece of flexible energy consumption and/or generation equipment is configured to consume and/or generate energy in response to the allocation of consumed/generated energy for the first time period (0 by the at least one of the plurality of energy tnonitors N); and the controller is configured to match a portion (Mit) of consumed/generated energy during the first time period (t) of each energy monitor of N), less the consumed/generated energy for the first time period (0 allocated to the at least one (P) piece of flexible energy consumption and/or generation equipment, with a source/sink selected from the plurality (N) of other energy monitors, based on the respective equipment energy data (Eit) for the first time period (t) from each energy monitor (i) (i.e. Mt Et,t - FiLt Or The controller may be a single controller, for example embodied on a physical and/or distributed server. Alternatively or additionally, the controller may be distributed over the plurality of energy monitors, each energy monitor including a sub-controller for performing a subset of the operations of the controller.

Pieces of energy consumption and/or generation equipment that are not pieces of flexible energy consumption and/or generation equipment are inflexible energy consumption and/or generation equipment; that is, their consumption and/or generation during a given time period is not convenient to control to balance the sub-network's generation and consumption (e.g. lighting, computer power, cooking, etc.).

A subnetwork may comprise a microgrid, and may be a geographically localised group of energy generation equipment, energy storage equipment, and energy consumption equipment (e.g. loads). A subnetwork may be connected to a centralised grid (e.g. a macrogrid, such as a national grid, a regional distribution network and/or a transmission/distribution network) at a single point that operates as an input or an output, depending on the energy consumption/generation of the microgrid. Alternatively, a microgrid may be isolated permanently, semi-permanently, occasionally and/or temporarily.

Tn some arrangements, a microgrid may be defined as comprising all connected components within the geographically localised group, or that are connected to the centralised grid via the single point, or even all components connected to the low voltage side of the transformer and/or substation. Alternatively, the microgrid may be defined as that part of the geographically localised group and/or connected components that may be subject to monitoring and/or control by the microgrid control apparatus of the present invention.

Alternatively or additionally, a subnetwork may be a cloud-based network; that is, the subnetwork may comprise a subset of an existing network, for example a group of network nodes that may exclude some or all network nodes therebehveen.

Energy generation equipment, energy storage equipment, and energy consumption equipment may be connected in a microgrid at low voltage or very low voltage, for instance via low voltage feeders or low voltage feeder cables. Low voltage may be below approximately 500V, 400V, 300V, 250V, 240V, 230V or 220V. Very low voltage may be below approximately 100V, for example below 60V or below SOY. The microgrid may operate on DC or AC. The input/output of the microgrid is usually a transformer and/or substation, for instance a 21\71W substation. The isolating transformer/substation may have a power rating of below approximately 50MVA" 401\1VA, 201\1VA, 101\1VA, smy-A, 4MYA. 3m\TA, 2MVA, FARTA, 500kVA" 400kVA, 300kVA or 230kVA. The microgrid may comprise a local energy network, power lines, cables, substations, transformers, distribution wiring, meters, junction boxes, switches and/or circuit breakers.

The above and other characteristics, features and advantages of the present invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention. This description is given for the sake of example only, without limiting the scope of the invention. The reference figures quoted below refer to the attached drawings.

Figure 1 shows a configuration of a subnetwork.

The present invention will be described with respect to certiin drawings but the invention is not limited thereto but only by the claims. The drawings described are only schematic and arc non-limiting. Each drawing may not include all of the features of the invention and therefore should not necessarily be considered to be an embodiment of the invention. In the drawings, the size of some of the elements may be exaggerated and not drawn to scale for illustrative purposes. The dimensions and the relative dimensions do not correspond to actual reductions to practice of the invention.

Furthermore, the terms first, second, third and the like in the description and in the claims, are used for distinguishing between similar elements and not necessarily for describing a sequence, either temporally, spatially, in ranking or in any other manner. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that operation is capable in other sequences than described or illustrated herein. Likewise, method steps described or claimed in a particular sequence may be understood to operate in a different sequence.

Moreover, the terms top, bottom, over, under and the like in the description and the claims are used for descriptive purposes and not necessarily for describing relative positions. it is to be understood that the terms so used are interchangeable under appropriate circumstances and that operation is capable in other orientations than described or illustrated herein.

Tt is to be noticed that the term "comprising", used in the claims, should not be interpreted as being restricted to the means listed thereafter; it does not exclude other elements or steps. It is thus to be interpreted as specifying the presence of the stated features, integers, steps or components as referred to, but does not preclude the presence or addition of one or more other features, integers, steps or components, or groups thereof Thus, the scope of the expression "a device comprising means A and B" should not be limited to devices consisting only of components A and B. It means that with respect to the present invention, the only relevant components of the device are A and B. Similarly, it is to be noticed that the term "connected", used in the description, should not be interpreted as being restricted to direct connections only. Thus, the scope of the expression "a device A connected to a device B" should not be limited to devices or systems wherein an output of device A is directly connected to an input of device B. It means that there exists a path between an output of A and an input of B which may be a path including other devices or means. "Connected" may mean that two or more elements are either in direct physical or electrical contact, or that Iwo or more elements are not in direct contact with each other but yet still co-operate or interact with each other. For instance, wireless connectivity is contemplated.

Reference throughout this specification to "an embodiment" or "an aspect" means that a particular feature, structure or characteristic described in connection with the embodiment or aspect is included in at least one embodiment or aspect of the present invention. Thus, appearances of the phrases "in one embodiment", "in an embodiment", or "in an aspect" in various places throughout this specification are not necessarily all referring to the same embodiment or aspect, but may refer to different embodiments or aspects. Furthermore, the particular features, structures or characteristics of any one embodiment or aspect of the invention may be combined in any suitable manner with any other particular feature, structure or characteristic of another embodiment or aspect of the invention, as would be apparent to one of ordinary skill in the art from this disclosure, in one or more embodiments or aspects.

Similarly, it should be appreciated that in the description various features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of One or more of the various invuttivc aspects. This inutliod of disclosure, however, is not to be interpreted as reflecting an intention that the chimed invention requires more features than are expressly recited in each claim. Moreover, the description of any individual drawing or aspect should not necessarily be considered to be an embodiment of the invention. Rather, as the following claims reflect, inventive aspects lie in fewer than all features of a single foregoing disclosed embodiment. Thus, the claims following the detailed description are hereby expressly incorporated into this detailed description, with each claim standing on its own as a separate embodiment of this invention.

Furthermore, while some embodiments described herein include some features included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the invention, and form yet further embodiments, as will be understood by those skilled in the art For example, in the following claims, any of the claimed embodiments can be used in any combination.

In the description provided herein, numerous specific details arc set forth. However, it is understood that embodiments of the invention may be practised without these specific details. In other instances, well-known methods, structures and techniques ii have not been shown in detail in order not to obscure an understanding of this description.

TI1 the discussion of the invention, unless stated to the contrary, the disclosure of alternative values for the upper or lower limit of the permitted range of a parameter, coupled with an indication that one of said values is more highly preferred than the other, is to be construed as an implied statement that each intermediate value of said parameter, lying between the more preferred and the less preferred of said alternatives, is ielf preferred to said less preferred value and also to each value lying between said less preferred value and said intermediate value.

The use of the term "at least one" may mean only one in certain circumstances.

The use of the term "any" may mean "all" and/or "each" in certain circumstances. The principles of the invention will now be described by a detailed description of at least one drawing relating to exemplary features. It is clear that other arrangements can be configured according to the knowledge of persons skilled in the art without departing from the underlying concept or technical teaching, the invention being limited only by the terms of the appended claims.

Figure 1 shows a portion of a network, termed in this application a sub-network. Connection to the network is shown by the line 100. There may be only one, at least one, or more than one input/output from the sub-network to a wider network. For example, in a typical domestic street, a low-voltage network of the street is likely to have two points of connection to an intermediate-voltage network, each with a transformer. 't his is done in case one of the transformers fails.

A plurality of energy monitors 200 are shown connected to the network connection 100, each energy monitor provided with an index between 1 and N (four energy monitors 100 are shown for clarity: 1, 2, ...,i, N).

A plurality of pieces of energy consumption and/or generation equipment 300 are shown connected to the energy monitors 200, such that each piece of energy consumption and/or generation equipment 300 is associated with (and connected to) a single one of the energy monitors 200, and each energy monitor 200 is associated with (and connected to) at least one of the pieces of energy consumption and/or generation equipment 300. Only seven pieces of energy consumption and/or generation equipment 300 are shown in the figure, and have thus been provided with an index between a and g; however, it is to be appreciated that any number of pieces may be employed without loss of generality. These may be termed pieces of energy consumption and/or generation equipment 300 may be termed 'inflexible' pieces of energy consumption and/or generation equipment 300.

A plurality of pieces of flexible consumption and/or generation equipment 400 arc also shown, each provided with an index between 1 and P (six pieces of flexible consumption and/or generation equipment 400 are shown for clarity: 1, 2, 3, 4, ..., j, P).

Further, the respective pieces of energy consumption and/or generation equipment (both inflexible 300 and flexible 400) may be removed and/or added to the subnetwork during operation of the system, such that the total number of pieces of equipment, and their respective attributes, vary over time.

Each piece of flexible consumption and/or generation equipment 400 is associated with (and connected to) one of either the energy monitors 200 or one of a plurality of further energy monitors 500. The further energy monitors 500 are also connected to the network connection 100, each further energy monitor 500 provided with an index between 1 and 0 (four further energy monitors 500 are shown for clarity: 1, 2, For a prior time period (t-i):-Each (i of N) energy monitor (200) monitoring energy consumption and generation by the at least one respective (a to g) piece of energy consumption and/or generation equipment (300) to produce respective equipment energy datt (E,, i) for the prior time period (t-1).

The plurality (N) of energy monitors (200) may optionally share the equipment energy data (Etta) for the prior time period (t-1) with each other, and/or with a central processor for controlling the energy flow within the subnetwork.

Matching a portion (Mi,,i) of consumed/generated energy (E,,,i) during the prior time period (t-1) of each energy monitor (i of N) with a source/sink selected from the plurality (N) of other energy monitors (200). This matching may be achieved based on the respective equipment energy data (Pio i) for the prior time period (t-1) from each energy monitor (i). However, the matching may be achieved based on sending, broadcasting and/or advertising a proposal for a portion i) to at least one (or potentially all) of the other energy monitors (200), or to a central processor. Alternatively or additionally, the matching may be achieved by a central processor in posession of some or all of the equipement energy datea (EA. The magnitude of the matched portion (Mi,, 1) will always be less than that of the consumed/generated energy (4t1); i.e. Any unmatched consumed/generated energy (Di., 1=4, 1-Alio 1) during the prior time period (t-1) of each energy monitor (i of N) may be assigned to the input/output of the subnetwork.

A forecast (E1,t) may be made of energy consumption and/or generation by the at least one respective (a to g) piece of energy consumption and/or generation equipment (300) of each (i °EN) energy monitor (200) for a first (future) time period (t). Any forecast method is possible, but for simplicity here a persistance forecast will be employed such that Eis = Allocating consumed/generated energy (E jAij,t) for the first time period (t) of at least one (i of N) of the plurality of energy monitors (200) to the at least one (j of P) piece of flexible energy consumption and/or generation equipment (400), the allocated consumed/generated energy (E Aim) For the first time period (t) less than or equal to a predicted unmatched consumed/generated energy (Di,t) during the first time period (t) of the at least one of the plurality of energy monitors (i of N). Again, for simplicity if a persistence forecast is used, Di,t= For the first time period (t:-The at least one piece of Flexible energy consumption and/or generation equipment (400) consuming and/or generating energy in response to the allocation of consumed/generated energy for the first time period (t) by the at least one of the plurality of energy monitors (200).

the or each of the energy monitors (200) and/or further energy monitors (500) associated with the at least one piece of flexible energy consumption and/or generation equipment (400) monitoring energy consumption and/or generation by the at least one piece of flexible energy consumption and/or generation equipment (400) during the first time period (t) to produce respective flexible equipment energy data (4) for the first time period (t).

Each energy monitor (200) monitoring energy consumption and/or generation by the at least one respective piece of energy consumption and/or generation equipment (300) during the first time period (t) to produce respective equipment energy data (4,) for the first time period (t).

Optionally, it may be determined whether the total energy consumption and/or generation by the at least one piece of flexible energy consumption and/or generation equipment (300) during the first time period (t) equals the allocated consumed/generated energy for the first time period (Ei Fiipt = In this way, it can be established whether the flexible equipment has responded as requested, and penalties may be applied where it has not.

The plurality (N) of energy monitors (200) and/or at least one (Q) further energy monitors (300) may optionally share the equipment energy clati (ED and the flexible equipment energy data (fo) for the first time period (t) with each other, and/or with a central processor for controlling the energy flow within the subnetwork.

As above, matching a portion (ML) of consumed/generated energy (R,,i) during the first time period (t) of each energy monitor (i of N), less the consumed/generated energy for the first time period (t) allocated to the at least one (P) piece of flexible energy consumption and/or generation equipment (E j with a source/sink selected from the plurality (N) of other energy monitors, based on the respective equipment energy data (Ei,) for the first time period (t) from each energy monitor (i).

Any unmatched and unallocated consumed/generated energy (Di jt = Ejt -E j j,t) during the first time period (t) of each energy monitor (i of N) may be assigned to the input/output of the subnetwork. In an alternative approach, instead of accounting for the allocated amount, the actual amount produced/consumed by the flexible equipment may be considered (i.e. D1 = Eis -M1 -E j A forecast (E,jjt+i) may be made of energy consumption and/or generation by the at least one respective (a to g) piece of energy consumption and/or generation equipment (300) of each (i of N) energy monitor (200) for a second (future) time period (t+ 1) . Allocating consumed/generated energy ilijit+i) for the second time period (t+1) of at least one (i of N) of the plurality of energy monitors (200) to the at least one (j of P) piece of flexible energy consumption and/or generation equipment (400), the allocated consumed/generated energy (E1 A11+1) for the second time period (t+1) less than or equal to a predicted unmatched consumed/generated energy during the first time period (t) of the at least one of the plurality of energy monitors (i of N).

Claims

CLAIMS1. A method of controlling energy How within a subnetwork, the subnetwork having aninput/output (100), the method comprising the steps of: providing a plurality (N) of energy monitors (200), each energy monitor (i of N) associated with at least one respective piece of energy consumption and/or generation equipment (300) in the subnetwork; providing at least one (P) piece of flexible energy consumption and/or generation equipment (400), the or each (I of P) piece of flexible energy consumption and/or generation equipment ',400) associated with one (i of N) of the plurality (N) of energy monitors (200) and/or at least one (k of Q) further energy monitor (500); allocating a first amount of consumed/generated energy for a first time period of at least one of the plurality of energy monitors (i of N) to the at least one (P) piece of flexible energy consumption and/or generation equipment; the at least one (P) piece of flexible energy consumption and/or generation equipment consuming and/or generating energy in response to the allocation of COT ISLIT 1Cd /gCn Crated energy for the first tune period by the at least one of the plurality of energy monitors (i of N); each energy monitor (i of N) monitoring energy consumption and/or generation by the at least one respective piece of energy consumption and/or generation equipment during the first time period to produce respective equipment energy data for the first time period; and matching a portion of consumed/generated energy during the first time period of each energy monitor (i of N) with a source/sink selected from the plurality (N) of other energy monitors, based on the respective equipment energy data for the first time period from each energy monitor (i).
2. The method of controlling energy flow within a subnetwork of claim 1, further comprising the step of: prior to allocating the first amount, making a first forecast of energy consumption and/or generation by the at least one respective piece of energy consumption and/or generation equipment of each energy monitor (i of N) during a first time period; wherein allocating the first amount of consumed/generated energy for a first time period of at least one of the plurality of energy monitors (i of N) to the at least one (P) piece of flexible energy consumption and/or generation equipment is in response to the first forecast.
3 The method of controlling energy flow within a subnetwork of claim 1 (Jr claim 2, further comprising the steps of: making a second forecast of energy consumption and/or generation by the at least one respective piece of energy consumption and/or generation equipment of each energy monitor (i of N) during a second time period; and allocating a second amount consumed/generated energy for a second time period of at least one of the plurality of energy monitors (i or Nj to the at least one (P) piece of flexible energy consumption and/or generation equipment, in response to the second forecast.
4. The method of controlling energy flow within a sulanetvork of claim 3, wherein: the second amount is less than or equal to unmatched consumed/generated energy during the first time period of the at least one of the plurality of energy monitors (i of N).
5. The method of controlling energy flow within a subnetwork of any preceding claim, further comprising the steps oft each energy monitor (i of N) monitoring energy consumption and/or generation by the at least one respective piece of energy consumption and/or generation equipment during an earlier time period to produce respective equipment energy data for the earlier time period; and matching a portion of consumed/generated energy during the earlier time period of each energy monitor (i of N) with a source/sink selected from the plurality (N) of other energy monitors, based on the respective equipment energy data for the earlier time period from each energy monitor (i); wherein the first amount is less than or equal to unmatched consumed/generated energy during the earlier time period of the at least one of the plurality of energy monitors (i of N)
6. The method of controlling energy flow within a subnetwork of any preceding claim, further comprising the step of: the plurality (N) of energy monitors sharing the equipment energy data with each other.
7. The method of controlling energy flow within a subnetwork of any preceding claim further comprising the steps of: the or each 0 of P) of the energy monitors and/or further energy monitors associated with the at least one (P) piece of flexible energy consumption and/or generation equipment monitoring energy consumption and/or generation by the at least one (P) piece of flexible energy consumption and/or generation equipment during the first time period to produce respective flexible equipment energy data for the first time period; and determining whether the total energy consumption and/or generation by the at least one (P) piece of energy consumption and/or generation equipment during the first time period equals the allocated consumed/generated energy for the first time period.
8. The method of controlling energy flow within a subnetwork of claim 7, further comprising the step of: the plurality (N) of energy monitors and/or at least one (Q) further energy monitors sharing the equipment energy data and the flexible equipment energy data with each other.
9. The method of controlling energy flow within a subnetwork of any preceding claim further comprising the step of: assigning any unmatched consumed/generated energy during the earlier time period of each energy monitor (i of N) with the input/output of the subnetwork.
10. The method of controlling energy flow within a subnetwork of any preceding claim, further comprising the step of: assigning any unmatched and unallocated consumed/generated energy during the first time period of each energy monitor of N) with the input/output of the subnetwork.
11. A system for controlling energy flow within a subnetwork having an input/output, the system comprising: a plurality (N) of energy monitors, each energy monitor (i of N) associated with at least one respective piece of energy consumption and/or generation equipment in the subnetwork, each energy monitor (i of N) monitoring energy consumption and/or generation by the at least one respective piece of energy consumption and/or generation equipment during a first time period to produce respective equipment energy data for the first time period; at least one (P) piece of flexible energy consumption and/or generation equipment, the or each 0 of P) piece of flexible energy consumption and/or generation equipment associated with one of the plurality (N) of energy monitors or at least one (Q) further energy monitor; and a controller configured to allocate a first amount of consumed/generated energy for the first time period of at least one of the plurality of energy monitors (i of N) to the at least one (P) piece of flexible energy consumption and/or generation equipment; wherein: the at least one (P) piece of flexible energy consumption and/or generation equipment is configured to consume and/or generate energy in response to the allocation of consumed/generated energy for the first time period by the at least one of the plurality of energy monitors (i of N); and the controller is configured to match a portion of consumed/generated energy during the first time period of each energy monitor (i of N), less the consumed/generated energy for the first time period allocated to die at least one (P) piece of flexible energy consumption and/or generation equipment, with a source/sink selected from the plurality (N) of other energy monitors, based on the respective equipment energy data for the first time period from each energy monitor (i).