Ground-based heat sink facilitating electronic system cooling

1. A method comprising:

providing a coolant loop;

providing a ground-based heat sink controllably coupled to the coolant loop, the ground-based heat sink comprising:

a housing including a compartment, a coolant inlet, and a coolant outlet, the housing being configured for a coolant to flow from the coolant inlet through the compartment to the coolant outlet, the coolant transferring heat extracted from one or more electronic components; and

at least one heat pipe comprising a first portion disposed within the compartment of the housing and a second portion disposed outside the housing, the at least one heat pipe being configured to extract heat from the coolant flowing through the compartment and to transfer the extracted heat to the second portion disposed outside of the housing, wherein the second portion of the at least one heat pipe outside the housing facilitates conducting the extracted heat to the ground;

providing a heat rejection unit controllably coupled to the coolant loop, the heat rejection unit configured to reject heat from coolant passing therethrough to air passing across the heat rejection unit;

providing a controller coupled to control flow of coolant within the coolant loop through the ground-based heat sink and through the heat rejection unit based, at least in part, on at least one monitored variable;

wherein the ground-based heat sink and the heat rejection unit are controllably coupled to the coolant loop in series, the ground-based heat sink being coupled to the coolant loop upstream of the heat rejection unit and the coolant passes through the ground-based heat sink before passing through the heat rejection unit, and the controller is configured to automatically control flow of coolant within the coolant loop through the ground-based heat sink based, at least in part, on the at least one monitored variable, and to automatically control flow of coolant within the coolant loop through the heat rejection unit based, at least in part, on the at least one monitored variable;

providing a first bypass line and a first diverter valve coupled to the coolant loop between the ground-based heat sink and the heat rejection unit, the controller automatically controlling the first diverter valve to control an amount of coolant to pass through the heat rejection unit based, at least in part, on the at least one monitored variable, the controller allowing the coolant to pass through or preventing the coolant from passing through the heat rejection unit by control of the first diverter valve; and

providing a second bypass line and a second diverter valve coupled to the coolant loop upstream of the ground-based heat sink, the controller automatically controlling the second diverter valve to control an amount of coolant to pass through the ground-based heat sink based, at least in part, on the at least one monitored variable, the controller allowing the coolant to pass through the ground-based heat sink or preventing the coolant from passing through both the ground-based heat sink and the heat rejection unit by control of the second diverter valve.

2. The method of claim 1 , wherein the housing with the compartment resides below-ground and, in operation, a working fluid vapor rises within the at least one heat pipe from the evaporative region to the condenser region thereof.

3. The method of claim 2 , wherein the heat sink comprises a plurality of heat pipes, each heat pipe of the plurality of heat pipes comprising a first portion disposed within the compartment of the housing and a second portion disposed outside of the housing, and each heat pipe being configured to extract heat in an evaporative region of the first portion from the coolant flowing through the compartment and to transfer the extracted heat to the second portion of the heat pipe disposed outside the housing, wherein the second portion of the heat pipe outside the housing is configured with a condenser region at least partially buried within the ground to facilitate conducting the extracted heat to the ground.

4. The method of claim 1 , further comprising providing an adjustable fan associated with the heat rejection unit for facilitating moving air across the heat rejection unit and thereby controlling rejection of heat from the coolant passing through the heat rejection unit to the air passing across the heat rejection unit, the controller controlling speed of the adjustable fan based on, at least in part, the at least one monitored variable.

5. The method of claim 4 , wherein the controller automatically controls operation of the adjustable fan, the amount of coolant passing through the heat rejection unit, and the amount of coolant passing through the ground-based heat sink to maintain a monitored variable of the at least one monitored variable within a set range.

6. The method of claim 1 , wherein the coolant loop is a secondary coolant loop and the method further comprises:

providing a primary coolant loop distinct from the secondary coolant loop, the primary coolant loop facilitating removal of heat from one or more electronic systems; and

providing a liquid-to-liquid heat exchanger, the liquid-to-liquid heat exchanger being coupled in fluid communication with both the primary coolant loop and the secondary coolant loop, and the liquid-to-liquid heat exchanger facilitating transfer of heat from the primary coolant loop to the secondary coolant loop.