Hello,

I'm currently developing a solar battery package to operate a range of valves and actuators as well as associated control devices and telemetry in remote applications.

Below is the calculation procedure I have used to determine the amount of solar energy available from a single panel.

A ‘Peak Sun Hour’ is an hour in which 1kW/m2 hits the solar panel. Thus, if the average solar irradiance (kWh/m2) per day for a particular location is known, the number of ‘Peak Sun Hours’ can be found by dividing this value by 1kW/m2.

Panels are rated for a cell temperature of 25oC. For every degree above this, the maximum power output from the column reduces by a small percentage. This seems to be 0.4%/oC for Jinko’s Eagle range which is what I have looked at so far.

The least amount of sunlight is going to be received during winter. Thus a winter average (June, July & August) solar irradiance is going to represent an average minimum value.

The warmest conditions are going to occur during summer. Thus a summer average (December, January & February) maximum temperature is going to represent an average maximum value.

Combining this together, the minimum average output energy from the solar array would be:

Output Energy (Wh) = (Max Output Power (W) – Max Output Power (W) * [Temperature Coefficient of Pmax (%/oC) * (Average Max Summer Temperature (oC) – 25oC)]) * Peak Sun Hours (hrs)

Would this be a reasonable method to ensure I receive sufficient energy? There will be multiple days of battery capacity as a backup, but I want to make sure I can satisfy my load and fully charge these backup batteries in a day if sunlight is available.

I appreciate any advice you maybe able to provide.

I'm currently developing a solar battery package to operate a range of valves and actuators as well as associated control devices and telemetry in remote applications.

Below is the calculation procedure I have used to determine the amount of solar energy available from a single panel.

A ‘Peak Sun Hour’ is an hour in which 1kW/m2 hits the solar panel. Thus, if the average solar irradiance (kWh/m2) per day for a particular location is known, the number of ‘Peak Sun Hours’ can be found by dividing this value by 1kW/m2.

Panels are rated for a cell temperature of 25oC. For every degree above this, the maximum power output from the column reduces by a small percentage. This seems to be 0.4%/oC for Jinko’s Eagle range which is what I have looked at so far.

The least amount of sunlight is going to be received during winter. Thus a winter average (June, July & August) solar irradiance is going to represent an average minimum value.

The warmest conditions are going to occur during summer. Thus a summer average (December, January & February) maximum temperature is going to represent an average maximum value.

Combining this together, the minimum average output energy from the solar array would be:

Output Energy (Wh) = (Max Output Power (W) – Max Output Power (W) * [Temperature Coefficient of Pmax (%/oC) * (Average Max Summer Temperature (oC) – 25oC)]) * Peak Sun Hours (hrs)

Would this be a reasonable method to ensure I receive sufficient energy? There will be multiple days of battery capacity as a backup, but I want to make sure I can satisfy my load and fully charge these backup batteries in a day if sunlight is available.

I appreciate any advice you maybe able to provide.

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