The best solar system to power a refrigerator and four bulbs depends on several factors, including the power consumption of the appliances, the location where the solar system will be installed, and the amount of sunlight available in that location. To size the solar system correctly, you'll need to consider the following steps:
Determine the Power Consumption: Find out the power ratings or wattage of your refrigerator and each bulb. The power rating can usually be found on the appliance's label or in the user manual. For example, if your refrigerator consumes 100 watts and each bulb consumes 10 watts, you would have a total power consumption of 140 watts (100 watts for the fridge + 4 bulbs * 10 watts each).
Calculate Daily Energy Requirement: Determine the number of hours each appliance will be used daily. Multiply the power consumption of each appliance by the hours of daily usage to get the daily energy requirement in watt-hours (Wh). For example, if the refrigerator runs for 10 hours and the bulbs are used for 5 hours each day, you'd need 1400 Wh (140 watts * 10 hours) for the refrigerator and 200 Wh (4 bulbs * 10 watts * 5 hours) for the bulbs, totaling 1600 Wh.
Consider Battery Storage (Optional): If you want the solar system to provide power during periods of low sunlight (e.g., at night), you may need to add battery storage. The battery capacity will depend on the number of days you want the system to operate without direct sunlight. Let's say you want two days of autonomy; you'd need a battery bank that can store at least 3200 Wh (1600 Wh * 2 days).
Assess Solar Potential: Evaluate the solar potential of your location, taking into account the average number of peak sun hours per day. Peak sun hours are the hours during which the sun provides sufficient energy for efficient solar power generation. The more peak sun hours you have, the smaller the solar array and battery capacity you'll need.
Calculate Solar Panel Capacity: To determine the solar panel capacity needed, divide the daily energy requirement (including battery losses, if applicable) by the average peak sun hours. For example, if you have an average of 5 peak sun hours, you'd need a solar array capable of generating 3200 Wh / 5 hours = 640 watts.
Account for Efficiency and Safety Margin: Consider efficiency losses due to factors such as wiring, inverter losses, and temperature. Adding a safety margin of around 10-20% to your total system capacity is also recommended.
Choose Inverter and Charge Controller: Select an inverter that can handle the total wattage of your appliances. Ensure it has the necessary AC and DC output connections for your load. Additionally, choose a charge controller that is compatible with your solar panel capacity and battery type (if applicable).
Please note that the numbers provided above are for illustrative purposes only. The actual solar system requirements may vary based on your specific appliances and location. To design an accurate and efficient solar system, it's best to consult with a professional solar installer or engineer who can assess your needs and customize a system to suit your requirements.