PVsol presentation questions

[Litiantian]

as you can see in the image,

there is a numer called losses due to charge/discharge. could you please explain what is this mean and how do you caulculate this number?

theres is another number called lossed in batterie,  could you please explain what is this mean and how do you caulculate this number?

[developer_mo]

Hi Litiantian,

thanks for your questions.

On 5/28/2024 at 5:32 AM, Litiantian said:

there is a numer called losses due to charge/discharge. could you please explain what is this mean and how do you caulculate this number?

There are several factors that can lead to energy loss when charging and discharging the battery.

For example, if the battery system is only discharged with a low current it operates at a low level of efficiency. If the battery system includes a battery inverter, there are also conversion losses. These losses are caused by different efficiency rates in DC/DC or AC/DC conversion.

The manufacturer's specifications for the battery system serve as the basis for calculating the charging and discharging losses in PV*SOL. The efficiency is specified in our database for each battery system as a function of the utilization rate. For example, if the battery system is only loaded with a usage rate of 30 %, the efficiency of the system in the below example drops to 91 %. This means that 9 % is lost in the form of unusable energy.

On 5/28/2024 at 5:32 AM, Litiantian said:

theres is another number called lossed in batterie,  could you please explain what is this mean and how do you caulculate this number?

These losses are mainly caused by the internal resistance of the battery and by self-consumption of battery systems.

Battery storage systems require energy for their own operation, e.g. for battery management, cooling and monitoring systems. If energy is stored in a battery over a longer period of time, standby losses (losses when the battery is not used) can occur. These losses occur due to the self-discharge of the battery, i.e. the battery gradually loses energy even when it is not under load. The self-discharge rate depends on the battery type and the ambient temperature.

The basis for calculating the losses in the battery is the internal resistance of the battery and its self-discharge rate. These are stored in our database in the battery entries and are also based on the manufacturer's specifications.

I hope that answers your questions. If not, please contact me again.

Kind regards

Mikio