How to build an Inexpensive Geothermal Solar Air Conditioning System to Cool your Garage using an Old Car Radiator ,Solar Panel.

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This article provides detailed instructions on how to build a low-cost geothermal solar air conditioning system that harnesses the Earth’s natural cool temperature to cool down your garage or home.



By using a few feet of underground piping and a simple circulation system, this project creates an efficient and eco-friendly way to beat the heat without relying on traditional AC units.



One of the key features of this geothermal solar air conditioning system is its ability to harness the stable temperature that exists just a few feet below the Earth’s surface.



Regardless of the weather conditions above ground, the temperature at this depth remains consistently between 55 and 60 degrees Fahrenheit.



By tapping into this stable temperature, the system can siphon heat from inside your home and release it into the water or refrigerant in the loop.



This process works by circulating the liquid through a network of underground piping, where it comes into contact with the cool temperature of the Earth.


As the liquid passes through this environment, it cools down and is then pumped back into your home, providing a refreshing coolness.



In essence, the system acts as a heat exchanger, moving heat from your indoor environment to the cool underground temperature and then bringing the cooled liquid back to your home.



To build this inexpensive geothermal solar air conditioning system, you will need several materials. These include:

  1. Old car radiator – this will be used to circulate air using a solar panel.
  2. PVC drain pipe – used to transport the liquid out of the radiator.
  3. Circulator pump – this will be used to pump water from a well to the radiator.
  4. 55-gallon drum – this will be buried in the ground to keep the liquid cool.
  5. Charge controller – required for the solar panel to control the amount of electricity generated.
  6. DC to DC converter – this will convert the voltage from the solar panel to the correct voltage for the battery.
  7. 12 or 24V batteries – used to store the electricity generated by the solar panel.
  8. Temperature sensor – used to detect the indoor temperature and adjust the system accordingly.
  9. Coolant temperature sensor – this can be added to measure the temperature difference between the inlet and outlet to determine how much heat is being pulled into the water.
  10. 10-foot pipe – used in conjunction with the well to pump water up.
  11. Check valves – used to ensure the liquid flows in the correct direction.


If you have access to a free-flowing well that runs down a hill, you can take advantage of this natural source of water to power your geothermal solar air conditioning system.



In this case, when you draw the water well, you may find that the static water level is about 2 feet above the ground. This means that there is enough pressure in the well to allow water to flow without the need for a pump.



To use this water source with the geothermal system, you will need to connect it to a 55-gallon drum that is buried in the ground to keep the water cool.



This drum will act as a reservoir for the water that is used to cool the system. To ensure that the water circulates properly, you will need to use a circulator pump that will move the water from the well to the radiator.





To access the water, a 10-foot pipe is inserted into the well to act as a conduit to transport the water from the well to the surface.


Installing check valves in the system is critical to maintaining water pressure and ensuring the water flows in the correct direction.



To move the water from the well to the radiator, a cost-effective option is to use a cheap pump from a car.


Alternatively, if the water pressure in the well is sufficient, a natural siphoning process may be feasible.


In order to build a functional geothermal solar air conditioning system, acquiring an old car radiator is a critical requirement.



The radiator, as a vital component of the system, plays a key role in the circulation of air using a solar panel.


In this specific project, an old radiator sourced from a Volvo car was used, as it has been proven to be highly efficient and reliable.

Next step involves connecting the water inlet to the radiator, attaching the outlet to a PVC drain pipe, and linking the radiator to a motor that is powered by a solar panel.




This connection enables water to circulate through the radiator, absorb heat from the indoor air, and reduce the temperature before being drained out.


To optimize the geothermal solar air conditioning system’s performance, a temperature sensor is attached to the radiator fan to detect indoor temperature changes.



The pump used in this system is sourced from the same Volvo car as the radiator. Additionally, a coolant temperature sensor can be installed to measure the temperature difference between the inlet and outlet and gauge the amount of heat extracted from the air and transferred to the water.



These sensors enable real-time monitoring of the geothermal solar air conditioning system’s performance, allowing for timely detection of any issues that may impact its functionality.

This geothermal solar air conditioning system operates solely on solar power, making it an eco-friendly and cost-effective option.


However, to ensure efficient operation, a charge controller is required to regulate the amount of charge that the batteries receive.



Additionally, a DC to DC converter is necessary to manage the power supply and convert the DC power from the solar panel to the appropriate voltage for the system.



Finally, 12 or 24V batteries are needed to store the solar-generated power and provide consistent energy to the system

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