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The financial benefits of washing solar arrays at the right times

When it comes to cleaning solar panels, various factors need to be considered to determine whether the costs are worth the benefits. These factors include the size of the solar panel system, its location, the angle of the panels, the cost of local labor, and the potential advantages that regular cleaning can bring to the system's performance.

In some locations, the cost may not justify the benefits. However, there are cases where cleaning can significantly increase the panel's output, as seen with Spirit's solar panels on Mars. On Earth, snow and rain can clean solar panels effectively, but regional pollution can also reduce their performance. Despite this, electric utilities and large project owners may still choose to pay for panel cleaning, even though they may not always do it well, and this is something to be mindful of.

The benefits of optimizing solar panel cleaning

Optimizing solar panel wash cycles can provide significant financial benefits to solar panel owners and operators. Here are some of the key financial benefits:

  1. Increased energy production: As mentioned earlier, dirty solar panels can reduce their energy output. By optimizing the wash cycles, solar panel owners can maintain the maximum efficiency of their panels, leading to increased energy production. This increased energy production can result in higher revenue from the sale of electricity, as well as reduced energy costs for those using the electricity on-site.

  2. Extended panel lifespan: Regular cleaning of solar panels can extend their lifespan by preventing the buildup of dirt and other contaminants that can cause damage over time. This can result in lower maintenance costs and reduced replacement costs, which can add up to significant savings over the lifespan of the solar panels.

  3. Improved return on investment (ROI): The financial benefits of optimizing solar panel wash cycles can contribute to an improved return on investment. By increasing energy production and reducing maintenance and replacement costs, solar panel owners can achieve a faster payback period and ultimately generate greater profits over the lifespan of the panels.

  4. Compliance with warranty requirements: Many solar panel manufacturers require regular cleaning of their panels in order to maintain warranty coverage. By optimizing the wash cycles, solar panel owners can ensure that they comply with these requirements, avoiding the risk of voiding their warranty coverage and incurring costly repairs or replacements.

The cost of cleaning solar panels

The cost of washing solar panels can vary depending on a number of factors, such as the size of the solar array, the type of panels, location, and the method used for cleaning.

Some solar farms may use automated cleaning systems, such as robotic cleaners, which can be more expensive to install but can save money in the long run by reducing the need for manual labor. Others may use manual cleaning methods, such as using a hose and squeegee or using a water-fed pole system.

It's important to note that keeping solar panels clean can have a significant impact on their efficiency and output, which can ultimately affect the profitability of the solar farm. So while the cost of cleaning may vary, it can be a worthwhile investment for solar farm operators.

A smart solution to optimize wash cycles

The ARES soiling monitoring station measures local soiling loss on a daily basis, has its own onboard cell modem, and is self-powered (it’s got two solar cells built-in). The station measures irradiance and calculates daily insolation using large area reference cells. The top cell gets dirty while the bottom cell is cleaned daily (notice the tiny nozzles sticking out above the lower solar cell). This allows ARES to measure losses due to soiling. With this data, users can see the financial impact that array cleaning will have on their revenue. It's not unusual for our customers to report a 20% improvement in year-over-year bottom-line performance by using ARES soiling stations.

The above image is an example report from Fracsun's customer portal showing soiling loss at their site.

The above image is showing the wash nozzles that clean the bottom cell on an ARES soiling station.


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