How to Determine How Much Solar Power I Need?

How to Determine How Much Solar Power I Need?

Using the energy given by the sun is quite eco-friendly. Thus if you want to use it, you obviously need to determinate your consumption, and this article will help you.

From the beginning, you need to decide on what size is necessary for you, how much energy one solar collector can give to determine the right amount.

And also you need to understand that in addition to the panels themselves, you need batteries, the best rated solar generator, a charge controller, and a voltage converter (inverter).

Solar power calculation

To get to know the required power given by sun for your cells you need to know your energy consumption. For example, if your energy consumption is 100 kW/h per month, then you need solar collectors to produce this amount of energy.

Solar collectors themselves produce renewable energy only during daylight hours. And give out their declared power only when there are a clear sky and the sun’s rays at a right angle. When the sun rays fall at angles, the solar panels power drops noticeably, and as sharper the angle of incidence of sunlight, the more significant the drop in power. In cloudy weather, the power of solar cells drops in 15-20 times, even with light clouds and haze, the power of solar cells drops in 2-3 times, and all this must be taken into account.

Thus, the size of solar panels of 1 kW (1000 watts) for a sunny summer day will generate 7 kWh of electricity for a period from 9 am to 4 pm, and 210 kW/h per month. Plus, another 3 kW (30%) in the morning and evening, but let it be a reserve as it can be partly cloudy.

We think it is clear that if the array of panels will be at 2 kW, then the energy production will be 420 kW/h per month. And if there is one socket per 100 watts, then it will produce only 700 watts per hour of energy per day, and 21 kW per month.

It’s nice to have 210 kW/h per month from an array of the only 1kW, but it’s not that simple.

Firstly, there is no such thing that all 30 days in a month are sunny, so you need to look at the archive of weather in the region and find out how many roughly cloudy days by month. As a result, probably 5-6 days will definitely be cloudy.

You also need to understand that in the spring and autumn the daylight is shorter and cloudy days are much more, so if you want to use renewable energy from March to October, then you need to increase the number of solar collectors by 30-50% depending on the specific region.