A business wants to buy enough 130 W solar panels to generate an average of 220 kWh of solar electricity in a week. Averaging over many days, the business receives an equivalent of 12 hours of sunlight a day. How many solar panels does this business need to buy?

To generate an average of 220 kWh per week with 130 W solar panels and 12 hours of sunlight daily, the business would need to purchase 21 solar panels.

Explanation:

Calculating the Number of Solar Panels Needed

A business requires 130 W solar panels to generate an average of 220 kWh of power per week. With the equivalent of 12 hours of sunlight per day, we first determine the total weekly sunlight hours: 12 hours/day × 7 days/week = 84 hours/week.

To find the average hourly generation needed, we divide the total weekly energy requirement by the number of sunlight hours: 220 kWh/week ÷ 84 hours/week = 2.619 kWh/hour.

Since each panel is 130 W (or 0.130 kW), in one hour a single panel generates: 0.130 kW × 1 hour = 0.130 kWh. Therefore, the number of panels needed is the required hourly generation divided by the generation per panel: 2.619 kWh/hour ÷ 0.130 kWh/panel = 20.146 panels.

Rounding up since a partial panel cannot be purchased, the business needs to buy 21 solar panels to meet its energy goals.