The 4kW (4000W) rating of a solar system means that, provided there’s enough direct sunlight, the 4kW solar system can produce 4000W (Watts) or 4kW (kiloWatts) of power, or even more under the right conditions. Related: How much sunlight do solar panels need?
[pdf] The amount of electricity generated by a 36V 300W solar panel system can be estimated at 600 watt-hours daily under optimal conditions, 0.6 kWh daily, factoring in sunlight hours, efficiency losses, and weather conditions.
[pdf] One of the main differences in these models is how much charging “juice” they can store, referenced in watt-hours. Watt-hours are a measure of a unit of energy (watts) that can flow over time (hours). Consider.
[pdf]