Systems and methods to aggregate distributed energy resources
The present disclosure is directed to systems and methods for economically optimal control of an electrical system. Some embodiments employ generalized multivariable constrained continuous optimization techniques to determine an optimal control sequence over a future time domain in the presence of any number of costs, savings opportunities (value streams), and constraints. Some embodiments also include control methods that enable infrequent recalculation of the optimal setpoints. Some embodiments may include a battery degradation model that, working in conjunction with the economic optimizer, enables the most economical use of any type of battery. Some embodiments include techniques for load and generation learning and prediction. Some embodiments include consideration of external data, such as weather.
1 . A system of distributed energy resources (DERs), the system comprising:
an aggregation engine to communicate over a network with a plurality of site controllers of a plurality of sites, each of the plurality of sites comprising one or more DERs that provide power to an electrical system, each site controller of the plurality of site controllers to control a DER of the one or more DERs, the aggregation engine to:
receive an aggregation opportunity indicative of a requested power level production over a period of time of a response event of the aggregation opportunity;
provide, over the network, for each of the plurality of site controllers, an engagement rule set indicative of a proposed change in power during a proposed period of time, the proposed change in power comprising multiple power levels for multiple portions of the proposed period of time, wherein each of the plurality of site controllers is configured to:
use the engagement rule set to determine a marginal cost of participation for a respective site of the plurality of sites to participate in the response event of the aggregation opportunity, based at least on a predicted future load of the respective site determined using a corrected load shape of the respective site generated using at least a scale and an offset of a load shape of the respective site determined from observed load values corresponding to a local load of the respective site; and
define a hypothetical control parameter to control a DER of the respective site to meet the proposed change in power according to a plurality of segments of the period of time to minimize the marginal cost of participation for the respective site; and
control operation of one or more of the plurality of DERs by instructing, over the network, one or more of the plurality of site controllers to schedule one or more of the plurality of DERs for participation in the response event, responsive to one or more determined marginal costs of participation from each of the plurality of site controllers.
2 . The system DERs of claim 1 , wherein the engagement rule set comprises a proposed apportionment value for each given site of the plurality of sites based on one or more of:
a quantity of the plurality of sites;
a capacity of a battery of a given DER relative to a capacity of all batteries of the plurality of DERs;
a power output of a battery of the given DER relative to a total power output of all batteries of the plurality of DERs; and
assigning the total requested power level production as the proposed apportionment value.
3 . The system of DERs of claim 1 , wherein determining a marginal cost of participation for each of the plurality of sites comprises determining both a participation impact and a nonparticipation impact.
4 . The system of DERs of claim 1 , wherein determining a marginal cost of participation for each of the plurality of sites comprises determining a delta value indicating a difference in cost of the site participating in the response event versus not participating in the response event.
5 . The system of DERs of claim 1 , wherein determining a marginal cost of participation for each of the plurality of sites comprises consideration of an upshot to be received for providing the power level production over the period of time.
6 . The system of DERs of claim 5 , wherein the upshot is a function of power level production.
7 . The system of DERs of claim 1 , wherein participation in the response event comprises providing a portion of the requested power level production.
8 . The system of DERs of claim 7 , wherein providing a portion of the requested power level production comprises one or more of:
a reduction in consumed power; and
generation of electricity.
9 . The system of DERs of claim 1 , wherein the aggregation engine repeatedly polls each site controller of the plurality of site controllers in order to determine how to instruct the plurality of site controllers to schedule one or more of the plurality of DERs for participation in the response event.
10 . The system of DERs of claim 1 , wherein the proposed change in power is a fractional of the requested power level.
11 . A system of distributed energy resources (DERs), the system comprising:
a plurality of site controllers corresponding to a plurality of sites that each comprise one or more DERs to provide power to an electrical system, each site controller of the plurality of site controllers to control the one or more DERs of a respective site of the plurality of sites, each site controller of the plurality site controllers configured to:
receive an engagement rule set indicative of a proposed change in power during a proposed period of time;
determine, using the engagement rule set, a marginal cost of participation for the respective site of the plurality of sites to participate in a response event, based at least on a predicted future load of the respective site; and
define a hypothetical control parameter to control a DER of the respective site to meet the proposed change in power to minimize the marginal cost of participation for the respective site; and
an aggregation engine for aggregating the plurality of site controllers of a plurality of sites, the aggregation engine configured to:
receive an aggregation opportunity indicative of a requested power level production over a period of time of a response event of the aggregation opportunity;
provide, for each site controller of the plurality of site controllers, the engagement rule set; and
control operation of the one or more DERs of the plurality of sites by instructing one or more of the plurality of site controllers to schedule one or more of the DERs for the respective sites for participation in the response event of the aggregation opportunity, according to one or more determined marginal costs of participation from each of the plurality of site controllers.
12 . The system of DERs of claim 11 , wherein the predicted future load of the respective site is determined using a corrected load shape of the respective site that is generated using at least a scale and an offset of a load shape of the respective site determined from observed load values corresponding to a local load of the respective site.
13 . The system of DERs of claim 11 , wherein the proposed change in power comprises multiple power levels for multiple portions of the proposed period of time.
14 . The system of DERs of claim 11 , wherein the hypothetical parameter is defined to control the DER according to a plurality of segments of the proposed time period.