Abstract: An aggregation comprises: loads that draw electricity, and a hierarchy including a root dispatch engine at the top of the hierarchy, downstream dispatch engines each servicing downstream points comprising further downstream dispatch engines or loads, and the loads at the bottom of the hierarchy. Each downstream dispatch engine sends draw dispatches to its downstream points such that the total draw computed by summing the draw dispatches equals a draw dispatch received by the downstream dispatch engine from the dispatch engine above it in the hierarchy. The sent draw dispatches also satisfy downstream point draw constraints communicated to the downstream dispatch engine from its downstream points. In a method, a baseline long-term draw dispatch is determined for the aggregation, and the baseline long-term draw dispatch is modulated over a shorter time interval based on a short-term draw requirement to determine a draw dispatch for the aggregation.

Abstract: An aggregator is in operative communication with an aggregation of electric water heaters to receive thermostat readings and power consumption readings from the electric water heaters and to communicate demand response dispatch signals to the electric water heaters. The aggregator performs operations including: responding to instructions for a desired demand response by generating the demand response dispatch signals for the electric water heaters so as to cause the aggregation to draw electrical power providing the desired demand response; and determining whether an electric water heater of the aggregation has a failure and generating a notification of the failure. The determining including at least one of: determining whether the electric water heater has a failed heating element based on the thermostat readings received from the electric water heater; and determining whether the electric water heater has a water leak based on the power consumption readings received from the electric water heater.

Abstract: An aggregation comprises: loads that draw electricity, and a hierarchy including a root dispatch engine at the top of the hierarchy, downstream dispatch engines each servicing downstream points comprising further downstream dispatch engines or loads, and the loads at the bottom of the hierarchy. Each downstream dispatch engine sends draw dispatches to its downstream points such that the total draw computed by summing the draw dispatches equals a draw dispatch received by the downstream dispatch engine from the dispatch engine above it in the hierarchy. The sent draw dispatches also satisfy downstream point draw constraints communicated to the downstream dispatch engine from its downstream points. In a method, a baseline long-term draw dispatch is determined for the aggregation, and the baseline long-term draw dispatch is modulated over a shorter time interval based on a short-term draw requirement to determine a draw dispatch for the aggregation.

Abstract: In a direct load control system supporting frequency control of an electrical grid, at each electrical load of an aggregation of loads, a load status report is generated comprising an urgency value and a power level. At an aggregation dispatch controller, a dispatch signal is generated based on the generated load status reports and information indicative of electrical frequency. At each electrical load of the aggregation, the load is operated at the reported power level if the reported urgency value satisfies the dispatch signal and is not operated at the reported power level if the reported urgency value does not satisfy the dispatch signal.

Abstract: An aggregation comprises: loads that draw electricity, and a hierarchy including a root dispatch engine at the top of the hierarchy, downstream dispatch engines each servicing downstream points comprising further downstream dispatch engines or loads, and the loads at the bottom of the hierarchy. Each downstream dispatch engine sends draw dispatches to its downstream points such that the total draw computed by summing the draw dispatches equals a draw dispatch received by the downstream dispatch engine from the dispatch engine above it in the hierarchy. The sent draw dispatches also satisfy downstream point draw constraints communicated to the downstream dispatch engine from its downstream points. In a method, a baseline long-term draw dispatch is determined for the aggregation, and the baseline long-term draw dispatch is modulated over a shorter time interval based on a short-term draw requirement to determine a draw dispatch for the aggregation.

Abstract: A water heater that includes a cylindrical storage tank, at least one heating element, and at least one temperature sensor is modeled using a one-dimensional model that includes: a vertical stack of disks representing the water volume in the cylindrical storage tank, and a stack of annular segments surrounding the vertical stack of disks. The stack of annular segments represents the cylindrical wall of the cylindrical storage tank. The one-dimensional model may be used by a condition-based maintenance system comprising an electronic data processing device configured to detect a failure mode present in the water heater based on an output of the water heating model component. Some illustrative failure modes include insulation disturbance, heating element failure, excessive sediment buildup, or a drip tube rupture.

Abstract: In a direct load control system supporting frequency control of an electrical grid, loads are grouped into a plurality of load aggregations based on electrical power draw characteristics of the loads, e.g. power draw magnitude characteristic and transient slew rate. A best-fit dispatch signal is generated for each load aggregation to match a desired load response with a sum of predicted load responses of the aggregations each operating in accord with its best-fit dispatch signal. For each load aggregation, its best-fit dispatch signal is communicated to the loads of the load aggregation, and the loads of the load aggregation are operated in accord with the best-fit dispatch signal communicated to the loads. The desired load response may be generated based on historical Automatic Generation Control (AGC) signal data and at least one of (1) a weather forecast and (2) daily, weekly, and seasonal cycles.

Abstract: An aggregator is in operative communication with an aggregation of electric water heaters to receive thermostat readings and power consumption readings from the electric water heaters and to communicate demand response dispatch signals to the electric water heaters. The aggregator performs operations including: responding to instructions for a desired demand response by generating the demand response dispatch signals for the electric water heaters so as to cause the aggregation to draw electrical power providing the desired demand response; and determining whether an electric water heater of the aggregation has a failure and generating a notification of the failure. The determining including at least one of: determining whether the electric water heater has a failed heating element based on the thermostat readings received from the electric water heater; and determining whether the electric water heater has a water leak based on the power consumption readings received from the electric water heater.

Abstract: In a frequency control system, a system controller assigns load-specific threshold frequencies to electrical loads of a fleet of electrical loads. Load controllers perform load monitoring and control operations for controlled electrical loads of the fleet including (i) comparing a measurement of the electrical frequency with the threshold frequency assigned to the controlled electrical load and (ii) operating the controlled electrical load based on the comparison. For example, each load controller may perform operation (ii) by turning the controlled electrical load on if the measurement of the electrical frequency is greater than the threshold frequency assigned to the controlled electrical load, and turning the controlled electrical load off if the measurement of the electrical frequency is less than the threshold frequency assigned to the controlled electrical load. The threshold frequencies may be assigned based on State of Charge (SOC) values for the loads.

Abstract: A cold load pickup device includes a load controller comprising a microprocessor or microcontroller. The device is programmed to detect restoration of power after a power outage on a circuit powering an electric load. A power outage time for the power outage is determined, and a startup delay for the electric load is determined based on the power outage time. A startup delay mechanism, such as a power relay operated by the load controller or switching of the load on/off by the load controller, is configured to apply the startup delay after the detected restoration of power before restarting the electric load. In some embodiments, the startup delay for the electric load is determined based on the power outage time and a startup delay versus power outage time curve stored in a non-volatile memory of the load controller.

Abstract: Dispatch engines service endpoints by transmitting dispatch signals to the serviced endpoints that cause the endpoints to adjust their electric power consumption from the electric power grid in accord with a control signal received by the dispatch engine. A market interface dispatch engine receives its control signal from an electric power grid managing entity, and downstream dispatch engines form a hierarchy cascading downstream from the market interface dispatch engine with each downstream dispatch engine being an endpoint serviced by a dispatch engine located upstream in the hierarchy. The control signal received by each downstream dispatch engine comprises dispatch signals transmitted by the upstream dispatch engine. The endpoints further include electric power-consuming loads. A suitable load controller comprises separate power interface and logic elements operatively connected to define the load controller, with the logic element powered by low voltage DC power received from the power interface element.

Abstract: Loads on a distribution circuit are operated, which causes the loads to consume electricity delivered to the loads via the distribution circuit. A circuit voltage of the distribution circuit is measured. An excursion of the measured circuit voltage outside of a normal operating voltage range is responded to by triggering a sub-set of the loads on the distribution circuit to increase or decrease their power draw to counter the excursion. For an overvoltage condition, the responding comprises triggering a sub-set of the loads on the distribution circuit to operate, or increase their power draw, in order to reduce the circuit voltage. For an undervoltage condition, the responding comprises triggering a sub-set of the loads on the distribution circuit to cease operating, or reduce their power draw, in order to increase the circuit voltage.

Abstract: A load controller is connected with a residential electric load to regulate electric power drawn by the load from a residential a.c. electric power distribution system via power input terminals of the load. A voltmeter is connected to measure voltage at the power input terminals, and an ammeter is connected to measure electric current at the power input terminals. A microprocessor or microcontroller is programmed to compute a source impedance of the power distribution system as seen from the power input terminals using measured voltage and electric current at the power input terminals. The source impedance may be computed by determining an equivalent source voltage as equal to measured voltage at the power input terminals when the electric current at the power input terminals is zero, and computing the source impedance from measured non-zero electric current at the power input terminals in combination with at least the equivalent source voltage.

Abstract: A plurality of interactive electrical loads defines an aggregation connected with an electrical power grid. A scheduler generates a baseline power consumption schedule for the aggregation, determines frequency regulation capacity of the aggregation, and controls actual power consumption of the aggregation based on the baseline power consumption and an Automated Generation Control (AGC) signal of the electrical power grid to operate the aggregation as an ancillary frequency control device of the electrical power grid with the determined frequency regulation capacity.

Abstract: In a direct load control system supporting frequency control of an electrical grid, at each electrical load of an aggregation of loads, a load status report is generated comprising an urgency value and a power level. At an aggregation dispatch controller, a dispatch signal is generated based on the generated load status reports and information indicative of electrical frequency. At each electrical load of the aggregation, the load is operated at the reported power level if the reported urgency value satisfies the dispatch signal and is not operated at the reported power level if the reported urgency value does not satisfy the dispatch signal.

Abstract: In a direct load control system supporting frequency control of an electrical grid, at each electrical load of an aggregation of loads, a load status report is generated comprising an urgency value and a power level. At an aggregation dispatch controller, a dispatch signal is generated based on the generated load status reports and information indicative of electrical frequency. At each electrical load of the aggregation, the load is operated at the reported power level if the reported urgency value satisfies the dispatch signal and is not operated at the reported power level if the reported urgency value does not satisfy the dispatch signal.

Abstract: Dispatch engines service endpoints by transmitting dispatch signals to the serviced endpoints that cause the endpoints to adjust their electric power consumption from the electric power grid in accord with a control signal received by the dispatch engine. A market interface dispatch engine receives its control signal from an electric power grid managing entity, and downstream dispatch engines form a hierarchy cascading downstream from the market interface dispatch engine with each downstream dispatch engine being an endpoint serviced by a dispatch engine located upstream in the hierarchy. The control signal received by each downstream dispatch engine comprises dispatch signals transmitted by the upstream dispatch engine. The endpoints further include electric power-consuming loads. A suitable load controller comprises separate power interface and logic elements operatively connected to define the load controller, with the logic element powered by low voltage DC power received from the power interface element.

Abstract: Dispatch engines service endpoints by transmitting dispatch signals to the serviced endpoints that cause the endpoints to adjust their electric power consumption from the electric power grid in accord with a control signal received by the dispatch engine. A market interface dispatch engine receives its control signal from an electric power grid managing entity, and downstream dispatch engines form a hierarchy cascading downstream from the market interface dispatch engine with each downstream dispatch engine being an endpoint serviced by a dispatch engine located upstream in the hierarchy. The control signal received by each downstream dispatch engine comprises dispatch signals transmitted by the upstream dispatch engine. The endpoints further include electric power-consuming loads. A suitable load controller comprises separate power interface and logic elements operatively connected to define the load controller, with the logic element powered by low voltage DC power received from the power interface element.

Abstract: A load controller is connected with a residential electric load to regulate electric power drawn by the load from a residential a.c. electric power distribution system via power input terminals of the load. A voltmeter is connected to measure voltage at the power input terminals, and an ammeter is connected to measure electric current at the power input terminals. A microprocessor or microcontroller is programmed to compute a source impedance of the power distribution system as seen from the power input terminals using measured voltage and electric current at the power input terminals. The source impedance may be computed by determining an equivalent source voltage as equal to measured voltage at the power input terminals when the electric current at the power input terminals is zero, and computing the source impedance from measured non-zero electric current at the power input terminals in combination with at least the equivalent source voltage.

Abstract: A cold load pickup device includes a load controller comprising a microprocessor or microcontroller. The device is programmed to detect restoration of power after a power outage on a circuit powering an electric load. A power outage time for the power outage is determined, and a startup delay for the electric load is determined based on the power outage time. A startup delay mechanism, such as a power relay operated by the load controller or switching of the load on/off by the load controller, is configured to apply the startup delay after the detected restoration of power before restarting the electric load. In some embodiments, the startup delay for the electric load is determined based on the power outage time and a startup delay versus power outage time curve stored in a non-volatile memory of the load controller.