How many solar panels do I need?

To determine how much energy you want your solar panels to generate and choose panels that can meet those requirements, follow these steps:

1. Assess your energy consumption
   Start by understanding your current electricity consumption. Examine your past electricity bills to determine your average monthly and annual usage in kilowatt-hours (kWh). Identify any seasonal variations in your energy consumption.
2. Set your energy generation goal
   Decide how much of your energy needs you want your solar panels to meet. Some homeowners aim to offset a certain percentage of their electricity usage, while others aim for full energy independence. Determine the percentage or amount of energy you want your solar panels to generate.
3. Consider available roof space
   Evaluate the available roof space for solar panel installation. The size and number of panels you can install depend on the area of unobstructed roof space that receives sufficient sunlight. Consider factors like shading from nearby structures or trees that may impact the efficiency of your panels.
4. Calculate the required capacity
   Calculate the solar panel capacity needed to generate the desired amount of energy. Solar panel capacity is measured in watts (W) or kilowatts (kW). On average, a solar panel has a capacity of 250-400W. Divide your desired energy generation (in kWh) by the average daily sunlight hours in your area to estimate the required capacity. For example, if you want to generate 20 kWh per day and your area receives an average of 5 hours of sunlight, you would need panels with a total capacity of 4 kW (20 kWh ÷ 5 hours = 4 kW).
5. Consider panel efficiency
   Take into account the efficiency of the solar panels. Higher-efficiency panels can generate more electricity in the same amount of space. This is particularly important in areas with lower sunlight levels, such as Ireland. Look for panels with higher efficiency ratings to maximize energy generation within the available roof space.
6. Consult with solar installers
   Seek advice from professional solar installers or renewable energy experts. They can assess your specific situation, perform an on-site evaluation, and provide accurate calculations based on your energy needs and available roof space. They will consider additional factors such as panel orientation, tilt, and local weather conditions to determine the optimal solar panel configuration for your requirements.

By following these steps and consulting with experts, you can determine the energy generation goals and select solar panels that are capable of meeting your specific needs in Ireland.