Hierarchal framework for integrating distributed energy resources into distribution systems
Methods and apparatus are disclosed for providing a hierarchical framework for integrating distributed energy resources into power distribution systems. In one example of the disclosed technology, a method implemented with an aggregation server includes receiving a respective utility function associated with each of at least two of a plurality of distributed energy resources representing an amount of energy produced or consumed by the respective associated distributed energy resource as a function of energy price, producing an aggregated utility function associated with the plurality of distributed energy resources based on the received utility functions, transmitting the produced aggregated utility function to a coordinator, receiving a clearing value from the coordinator, and transmitting the received clearing value to each of the plurality of distributed energy resources.
1. A method comprising:
receiving, via a communication network coupled to a plurality of distributed energy resources, a respective utility function from each of at least two of the plurality of distributed energy resources, the respective received utility function representing an amount of energy produced or consumed by the respective associated distributed energy resource as a function of energy price;
producing an aggregated utility function associated with the plurality of distributed energy resources based on the received utility functions;
transmitting the produced aggregated utility function to a coordinator;
receiving a clearing value from the coordinator determined with the aggregated utility function; and
transmitting the received clearing value to each of the plurality of distributed energy resources, wherein determining the aggregated utility function comprises:
determining a demand function of the plurality of distributed energy resources based on the amount of energy produced or consumed by the plurality of distributed energy resources at each possible price, and
integrating an inverse function of the determined demand function over a range of energy consumption levels from a minimum amount produced or consumed to a maximum amount produced or consumed.
2. The method of claim 1 , wherein the aggregated utility function is determined based on a demand function associating a total amount of energy produced or consumed by the plurality of distributed energy resources for all possible energy prices.
3. The method of claim 1 , wherein at least one of the distributed energy resources is a load.
4. The method of claim 3 , wherein the utility function associated with the at least one of the distributed energy resources relates energy consumed to energy price.
5. The method of claim 1 , wherein at least one of the distributed energy resources is a distributed generator.
6. The method of claim 5 , wherein the utility function associated with the at least one of the distributed energy resources relates energy produced to energy price.
7. The method of claim 1 , wherein at least one of the received utility functions is determined by an end-user of its respective distributed energy resource.
8. The method of claim 1 , wherein at least one of the received utility functions indicates an end-user's preference for cost over comfort for its respective distributed energy resource.
9. The method of claim 1 , wherein at least one of the received utility functions is generated by a controller coupled locally to its respective distributed energy resource.
10. The method of claim 1 , wherein at least one of the received utility functions is transmitted by a resource controller coupled to its respective distributed energy resource.
11. The method of claim 1 , wherein the aggregated utility function is selected to attenuate or avoid the cobweb effect.
12. A system comprising:
a plurality of distributed energy resources being configured to transmit a utility function to at least one aggregation server, the utility function relating energy produced or consumed to energy price, the distributed energy resources being configured to determine whether to produce or consume energy based on a clearing value; and
the at least one aggregation server being configured to:
determine a first aggregated utility function based on the transmitted utility function, the first aggregated utility function relating energy produced or consumed by all of the distributed energy resources to price,
transmit the first aggregated utility function to a coordination server, the coordination server being configured to determine the clearing value based on each of a plurality of received aggregated utility functions comprising the first aggregated utility function and send the clearing value to the at least one aggregation server, and
transmit the clearing value to the plurality of distributed energy resources.
13. The system of claim 12 , wherein each aggregator is placed at a location where a voltage regulated transformer exists.
14. The system of claim 12 , further comprising a plurality of controllers, wherein each controller is configured to control one of the distributed energy resources.
15. The system of claim 12 , wherein at least one of the distributed energy resources is a load.
16. The system of claim 12 , wherein at least one of the distributed energy resources is at least one distributed generator.
17. The system of claim 16 , wherein the utility function associated with the at least one distributed generator relates energy produced to energy price.
18. The system of claim 12 , wherein the at least one aggregation server determines the first aggregated utility function by a demand function that relates an amount of energy produced or consumed by the distributed energy resources to a price; and
integrating an inverse function of the determined demand function over a range of energy produced or consumed from a minimum amount of energy to a maximum amount of energy.
19. The system of claim 12 , wherein the utility function associated with the at least one distributed energy resources relates energy consumed to energy price.
20. The system of claim 12 , further comprising:
the distributed energy resources comprising at least one or more of the following: a generator, an air-conditioning unit, heating unit, heating, ventilation, and air conditioning (“HVAC”) system, a hot water heater, a refrigerator, a dish washer, a washing machine, a dryer, an oven, a microwave oven; pump, a home lighting system, an electrical charger, an electric vehicle charger, or a home electrical system.
21. A system comprising:
a plurality of distributed energy resources being configured to transmit a bid to at least one aggregation server, the bid representing an amount of energy to be consumed by the resource during a time period and a bid price at which the energy will be consumed;
the at least one aggregation server being configured to:
determine a utility function representing a demand curve based on the bids received at the aggregation server for the plurality of distributed energy resources by summing the received bids that have a bid price less than a market cap price for; and
transmit the determined utility function to a coordination server; and
the coordination server being configured to determine a clearing value based at least in part on multiple different utility functions received from multiple different aggregation servers configured to produce respective utility functions for different respective aggregated electrical loads.