Setting up losses

Cabling and system losses settings

Cabling and Losses sections let you examine the default losses added to the design and change them if required. They are located within the Energy system designer in the main menu.

Cabling losses

Cabling losses can significantly impact the system’s efficiency. Therefore, they must be included in the calculation for higher simulation accuracy. Their values in the energy system designer are represented in percentages.

You can change the default cabling losses in the Cabling section.

1. Adjust the default values for different cabling sections as required.

2. The connection diagram helps you visualize the connections between components with numbered cable types for better identification.

Tip: You can examine the impact of cabling loss on overall system performance in the Evaluate Analytic’s PV system losses section.

System losses

In this section, you can examine and edit various system losses, such as degradation, auxiliary, unavailability, and environmental losses. They are located in the Losses category.

1. View and adjust any default values as required. Scroll down to reveal further parameters.

2. The values you have changed will have a “back” button to revert changes to the default.

Auxiliary losses

Auxiliary losses refer to the energy consumed by auxiliary systems and components in a solar power system that do not contribute to the primary energy output, impacting overall efficiency and performance.

The auxiliary losses can be set in percent or kW. Select the preferred method based on the required inputs.

Degradation losses

Degradation losses refer to the gradual reduction in solar panel efficiency over time due to various factors, leading to decreased energy output as the materials in the panels wear down. Default degradation values are added to the system. If you have detailed degradation data from the manufacturer, you can overwrite the default values for higher accuracy.

Environmental losses

Environmental losses refer to the reduction in solar energy output caused by external factors such as snow accumulation and soiling from dust, dirt, or debris on the solar panels, which obstruct sunlight and decrease efficiency.

• Default soiling and snow loss values: These are added to every design upon creation. You can adjust them using the respective “Edit” link. The method by which the losses were applied is indicated for each chart (default, manual, Solargis model).

• Simulated soiling and snow loss values: The designer offers a more accurate simulation of soiling and snow losses using our proprietary soiling and snow loss models. The estimation considers the solar resource data specific to your location and the configuration of your energy system, delivering more precise and location-specific results compared to using default values.

Simulated soiling and snow losses are provided in two charts: Monthly losses (%) and Monthly time series (%), each providing a different overview of the particular loss.

Analyzing the charts:

• Hovering the charts will reveal specific values for the given month.

• Toggle visibility of individual years and Long-term averages using the legend at the top of the chart.

• Expand the required visualization by clicking the chart header row.

Simulating snow and soiling losses

Important: Please be aware that soiling and snow simulations are available only after the initial project data generation (project activation).

The procedure is identical for both snow and soiling losses simulation, each using the respective soiling/snow model:

1. Click the “Edit” link of the respective loss you want to simulate and switch to the “Solargis model” tab.

2. Click “Simulate Solargis model” and wait for the result. The respective simulated loss will be calculated and displayed.

3. Click “Apply” to apply the losses to the system design.

Tip: For soiling losses, you can schedule monthly cleaning events before running the simulation to ensure they are included in the estimation. If you add cleaning events after the simulation has been completed, you will need to run the simulation again to include them in the results.

Note: If you want to add soiling or snow losses manually without using the Solargis model simulation, you can do it in the Manual tab. You can use up/down arrows to manually adjust the values.

Adding soiling cleaning events

Soiling losses are affected by cleaning events, and the Solargis soiling model includes these in the estimation. You can set your cleaning events based on your planned cleaning schedule, or you can plan your cleaning based on the Solargis model simulation (spotting the months where it is needed the most):

1. While in the respective loss edit mode, select the months you want to schedule cleaning.

2. Simulate the Solargis model to apply the cleaning events to the model calculation.

3. Save and apply the changes to the design by clicking the “Apply” button.  

Tip: Use the “Undo cleaning events” button to clear all new cleaning events to revert to the last simulation state.

Important:

• Any change to snow/soiling losses or system configuration requires re-simulation to update results.

• Changing configuration invalidates existing snow/soiling loss data; the system will notify you during validation.

• Simulations cannot run with invalidated snow/soiling losses unless you switch these losses to Manual mode.

Unavailability losses

Unavailability losses refer to the reduction in energy output due to periods when the solar power system is not operational, which can be classified into internal losses caused by equipment failures or maintenance and external losses due to factors like grid outages or environmental conditions.