Energy buffering using a heat pump
AssigneeMixergy Limited
InventorPeter ARMSTRONG
Life of this patent
Estimating the term…
Abstract
A heating system is provided. The heating system comprises a tank for holding fluid; a photovoltaic system; a heat pump arranged to provide heat to the tank; and a controller. The controller is configured to determine a quantity of heat stored in the tank relative to a target maximum quantity of heat that the heating system is adapted to store in the tank. The controller is configured to determine a level of solar power surplus electricity generated by the photovoltaic system. The controller is configured to change a power state of the heat pump on the basis of the quantity of heat stored in the tank relative to the target maximum quantity of heat that the heating system is able to store in the tank and the level of solar power surplus electricity.
Claims44
A heating system comprising:
- a tank for holding fluid;
- a photovoltaic system;
- a heat pump arranged to provide heat to the tank;
- and
- a controller configured to:
- determine a quantity of heat stored in the tank relative to a target maximum quantity of heat that the heating system is adapted to store in the tank;
- determine a level of solar power surplus electricity generated by the photovoltaic system;
- and
- on the basis of the quantity of heat stored in the tank relative to the target maximum quantity of heat, and the level of solar power surplus electricity, changing a power state of the heat pump.
A heating system according to any preceding claim, wherein the quantity of heat stored in the tank is determined at least in part using a temperature probe.
A heating system according to any preceding claim, wherein the quantity of heat stored in the tank is determined at least in part using a temperature sensor array comprising a plurality of temperature sensors.
A heating system according to any preceding claim, wherein the quantity of heat stored in the tank is determined at least in part using a flow meter.
A heating system according to any preceding claim, wherein the quantity of heat stored in the tank is determined at least in part using temperature sensors at the inlet and outlet of the tank.
A heating system according to any preceding claim, wherein the controller is further configured to determine additionally a length of time that would be required to raise the quantity of heat stored in the tank to the target maximum quantity of heat that the heating system is able to store in the tank.
A heating system according to any preceding claim, wherein the controller is further configured only to change the power state of the heat pump when the surplus electricity generated by the photovoltaic system exceeds a minimum threshold.
A heating system according to any preceding claim, wherein the controller determines the surplus electricity generated by the photovoltaic system as an electricity being exported to an external electricity grid and/or as a difference between an electricity generated by the photovoltaic system and a domestic electricity demand.
A heating system according to any preceding claim, wherein the controller is further configured only to change the power state of the heat pump when a predicted surplus electricity generated by the photovoltaic system exceeds a minimum threshold.
A heating system according to any preceding claim, wherein the change in power state of the heat pump is a binary change between an off state and an on state.
A heating system according to any preceding claim, further comprising a user interface.
A heating system according to any preceding claim, wherein one or more refrigerant coils and/or plate heat exchangers and/or coil heat exchangers are arranged to provide heat from the heat pump to the tank.
A heating system according to any preceding claim, wherein the controller is configured to reduce the power state of the heat pump if the surplus electricity generated by the photovoltaic system falls below a threshold.
A heating system according to any preceding claim, wherein the controller is configured to maintain the heat pump in the on state for at least a minimum period of time.
A heating system according to any preceding claim, wherein the controller is configured to determine whether to provide heat to an upper part of the tank for topping up a smaller hot volume of water, or to provide heat to a lower part of the tank for gradually heating the whole tank;
- and to actuate a means of diverting heat either to an upper part of the tank or to a lower part of the tank.
A method of controlling a heating system, the method comprising:
- determining a quantity of heat stored in a tank relative to a target maximum quantity of heat that the heating system is able to store in the tank;
- determining a level of solar power surplus electricity generated by a photovoltaic system;
- and
- on the basis of the quantity of heat stored in the tank relative to the target maximum quantity of heat that the heating system is able to store in the tank and the level of solar power surplus electricity, changing a power state of the heat pump.
Dependencies are inferred from the claim text.