Peak shifting and synchronization of compressor duty cycles for optimal energy efficiency

Abstract

A system for performing energy optimization of compressors used in refrigeration and HVAC (Heating Ventilation and Cooling) through the synchronization of or adjustment of run cycles so as to minimize overlapping energy demands and to reduce peak energy usage in a given measurement window resulting in lowered cap tag and demand based or transmission bill charges.

What is claimed: 
     
         1 . A system for controlled cycling of compressors comprising:
 software executing on a computer which software is connected via a network to at least one control device configured to control a plurality of compressors based on temperature readings;   the software is configured to receive temperature readings indicative of a temperature of each of a plurality of spaces, each space associated with one of the plurality of compressors;   the software further configured to receive data indicative of energy use of each compressor;   said software further connected to a storage which contains historical data indicative of operation patterns of each compressor associated with data indicative of one or more conditions associated with such operation patterns;   said software determining a predicated usage pattern for each of the plurality of compressors over a period of time based on data associated with a predicted condition for said period of time, said predicted usage pattern indicative of at least one cycle of each compressor being on and off and time periods associated with the compressor being on and off and a power usage during said time period associated with the compressor being on;   said software determining a modified cycle for each compressor such that at least a first group of one or more of the plurality of compressors is off or reduced in usage while at least a second group of one or more of the plurality of compressors is on or increased in usage relative to the predicted usage pattern;   said software generating control instructions for the at least one control device to modify a temperature setting and/or a temperature band for each space in order to control each compressor according to the modified cycle.   
     
     
         2 . The system of  claim 1  further comprising: said software monitoring the temperature readings compared to one or more thresholds and further modifying the modified cycle based one or more of the temperature readings falling outside of at least one of the one or more thresholds such that the software generates additional control instructions to control one or more of the plurality of compressors in response to the monitored temperature readings. 
     
     
         3 . The system of  claim 1  wherein said control instructions are configured to cause at least one of the one or more compressors to cycle on and off more frequently during the period of time. 
     
     
         4 . The system of  claim 1  wherein said control instructions are configured to cause at least one of the one or more compressors to remain on during an on cycle for a longer time period during the period of time. 
     
     
         5 . The system of  claim 1  wherein said control instructions are configured to cause at least one of the one or more compressors to remain on during an off cycle for a longer time period during the period of time. 
     
     
         6 . The system of  claim 1  wherein the modified cycle changes a start time for at least one of the plurality of compressors during the period of time relative to the predicted usage pattern. 
     
     
         7 . The system of  claim 1  wherein the predicted condition is a predicted weather and the one or more conditions associated with such operation patterns are one or more weather conditions. 
     
     
         8 . The system of  claim 1  wherein the control instructions are further generated or modified during the time period based on sensor data from sensors associated with one or more of the plurality of spaces which sensor data is measured during the time period and which sensors are sensors other than the temperature sensor which measures the temperature readings. 
     
     
         9 . The system of  claim 1  wherein the temperature band is a range of temperatures set relative to the temperature setting. 
     
     
         10 . The system of  claim 1  wherein the predicted condition is a predicted frequency and/or duration of opening of one or more doors associated with one or more of the plurality of spaces and the software monitors actual conditions associated with openings and/or duration of openings of the one or more doors during the time period and adjusts the control instructions based on a comparison of the actual conditions to the predicted conditions. 
     
     
         11 . A method for controlled cycling of compressors comprising:
 providing software executing on a computer which software is connected via a network to at least one control device configured to control a plurality of compressors based on temperature readings;   receiving temperature readings indicative of a temperature of each of a plurality of spaces, each space associated with one of the plurality of compressors;   receiving data indicative of energy use of each compressor;   obtaining historical data indicative of operation patterns of each compressor associated with data indicative of one or more conditions associated with such operation patterns;   determining a predicated usage pattern for each of the plurality of compressors over a period of time based on data associated with a predicted condition for said period of time, said predicted usage pattern indicative of at least one cycle of each compressor being on and off and time periods associated with the compressor being on and off and a power usage during said time period associated with the compressor being on;   determining a modified cycle for each compressor such that at least a first group of one or more of the plurality of compressors is off or reduced in usage while at least a second group of one or more of the plurality of compressors is on or increased in usage relative to the predicted usage pattern;   generating and transmitting control instructions with said software for the at least one control device to modify a temperature setting and/or a temperature band for each space in order to control each compressor according to the modified cycle.   
     
     
         12 . The method of  claim 11  further comprising: said software monitoring the temperature readings compared to one or more thresholds and further modifying the modified cycle based one or more of the temperature readings falling outside of at least one of the one or more thresholds such that the software generates additional control instructions to control one or more of the plurality of compressors in response to the monitored temperature readings. 
     
     
         13 . The method of  claim 11  wherein said control instructions are configured to cause at least one of the one or more compressors to cycle on and off more frequently during the period of time. 
     
     
         14 . The method of  claim 11  wherein said control instructions are configured to cause at least one of the one or more compressors to remain on during an on cycle for a longer time period during the period of time. 
     
     
         15 . The method of  claim 11  wherein said control instructions are configured to cause at least one of the one or more compressors to remain on during an off cycle for a longer time period during the period of time. 
     
     
         16 . The method of  claim 11  wherein the modified cycle changes a start time for at least one of the plurality of compressors during the period of time relative to the predicted usage pattern. 
     
     
         17 . The method of  claim 11  wherein the predicted condition is a predicted weather and the one or more conditions associated with such operation patterns are one or more weather conditions. 
     
     
         18 . The method of  claim 11  wherein the control instructions are further generated or modified during the time period based on sensor data from sensors associated with one or more of the plurality of spaces which sensor data is measured during the time period and which sensors are sensors other than the temperature sensor which measures the temperature readings. 
     
     
         19 . The method of  claim 11  wherein the temperature band is a range of temperatures set relative to the temperature setting. 
     
     
         20 . The method of  claim 1  wherein the predicted condition is a predicted frequency and/or duration of opening of one or more doors associated with one or more of the plurality of spaces and the software monitors actual conditions associated with openings and/or duration of openings of the one or more doors during the time period and adjusts the control instructions based on a comparison of the actual conditions to the predicted conditions.