Heat pump and auxiliary heating with carbon reduction reset strategy
A heat pump system includes a heat pump and an auxiliary heat source. A heating coefficient of performance is determined for the heat pump based on ambient outdoor air temperatures, and the heat pump is operated to heat a process fluid an output temperature based on the heating coefficient of performance and a reference heating coefficient of performance. The auxiliary heat source can be operated to bring the process fluid to a target temperature for heating a load, with the target temperature being a function of the ambient outdoor air temperatures.
1 . A heating system, comprising:
a heat pump configured to supply heat to a process fluid;
an auxiliary heating source configured to supply heat to the process fluid;
a controller, configured to:
determine a heating coefficient of performance of the heat pump based on an ambient outdoor air temperature;
determine a temperature target for the heat pump based on the determined heating coefficient of performance and a reference heating coefficient of performance; and
direct operation of the heat pump according to the determined temperature target,
wherein the controller is further configured to operate the auxiliary heating source to achieve an overall target temperature for the heating system,
wherein the controller is further configured to determine the overall target temperature for the heating system based on the ambient outdoor air temperature, and
wherein the overall target temperature for the heating system is determined by a linear function of the ambient outdoor air temperature.
2 . The heating system of claim 1 , wherein the reference heating coefficient of performance is a heating coefficient of performance of the auxiliary heating source.
3 . The heating system of claim 1 , wherein the auxiliary heating source is a fossil fuel boiler.
4 . The heating system of claim 1 , wherein the auxiliary heating source is an electric boiler.
5 . A method of controlling a heating system, comprising:
obtaining, at a controller, an ambient outdoor air temperature;
determining, using the controller, a coefficient of performance of a heat pump based on the ambient outdoor air temperature;
determining, using the controller, a target temperature for the heat pump based on the coefficient of performance and a reference coefficient of performance,
wherein the target temperature is determined such that the coefficient of performance is equal to or greater than the reference coefficient of performance and wherein the reference coefficient of performance is at least partially based on one or more of carbon output, energy cost, or target efficiency level;
determining, using the controller, an overall target temperature based on the ambient outdoor air temperature; and
operating the heat pump and an auxiliary heating source to add heat to a process fluid to achieve the overall target temperature in the process fluid;
wherein determining the overall target temperature is based on a linear function of the ambient outdoor air temperature.
6 . The method of claim 5 , wherein the reference coefficient of performance is a heating coefficient of performance of the auxiliary heating source.
7 . The method of claim 5 , wherein the auxiliary heating source is a fossil fuel boiler.
8 . The method of claim 5 , wherein the auxiliary heating source is an electric boiler.