DIY solar cooling system freezes water by day, cools homes at night

A Florida resident developed an off-grid solar cooling system that freezes water during the day to provide cooling at night, addressing the rising global electricity consumption from air conditioning. The system uses three 100-watt solar panels to charge a 35-amp-hour lead-acid battery via a charge controller. Once fully charged, a microcontroller activates an inverter powering a small refrigerator compressor running on R600 refrigerant, which cools a 2-gallon water bucket insulated with foam and fiberglass wool. Over several hours, the water freezes into ice, storing approximately 2.5 million joules of thermal energy, which remains frozen for days due to minimal heat leakage. Cooling is delivered through a glycol loop where a pump circulates a water-ethylene glycol mix through copper tubing inside the ice block. The chilled fluid passes through an automotive radiator with a fan, pushing cool air into the space. The pump and fan consume only a few watts, allowing operation after sunset without significant battery drain. Testing showed the system