The Demo site is a commercial solar PV installation is under water, and in a dusty environment (typical of many C&I and agricultural locations). Before the pilot, panel cleaning was manual and infrequent, constrained by labor cost and logistics. As a result, panels would accumulate dust buildup between cleanings, directly reducing energy output. The site owner sought a solution to maximize production without incurring high ongoing maintenance costs. Solaris Hydrobotics deployed its autonomous cleaning robot on a section of the array as a pilot test. One string of panels was fitted with the robot for daily cleaning, while an identical neighboring string remained uncleaned as a control reference. This setup provided a clear before-and-after comparison to quantify the robot’s impact.

Solaris Hydrobotics Solution: Solaris’s robot is a self-driving cleaner that traverses the panel rows at night, using a patented water-driven motor to move and scrub the panels solarishydrobotics.com. Unlike conventional cleaners, it requires no external electricity – pressurized water powers its movement and brush rotation. This design eliminates heavy rails or power cables and keeps operating costs low. The robot can clean on a schedule (e.g. nightly) or on-demand, and it’s built to withstand outdoor conditions for up to 10 years of servic. By using low-pressure water spray, it gently removes dust without scratching glass and uses minimal water compared to high-pressure washing. Crucially, the system’s autonomous operation means no technicians need to climb on roofs or utility structures, improving safety and avoiding labor risks. With this setup in place, Solaris and the site owner kicked off the pilot to measure performance improvements and financial benefits.

Results

Performance Uplift: The autonomous cleaner delivered a striking improvement in energy production. Over the test period, the robot-cleaned string consistently generated 15–20% more energy each day than the uncleaned string. On average, there was an 18% increase in daily energy yield attributable to the robot’s daily cleaning regimen. Figure 1 below illustrates a portion of the pilot data, showing daily production (in kWh) for both the cleaned and control strings. Prior to automation, the two strings produced similar energy (with minor variance due to soiling). Once Solaris’s robot began regular cleaning, the divergence is clear – the cleaned panels maintain higher output while the uncleaned panels drop off due to accumulating dirt.

Figure 1: Daily energy production per PV string during the Demo pilot. The Solaris robot began steady operation on May 2, after which the “With Robot” string (orange line) outperformed the identical “Without Robot” string (yellow line) by roughly 18% on average. In the days immediately after deployment, the cleaned panels gained a 15–20% output advantage. This validates that regular wet-cleaning restores lost output and keeps panels operating at peak capacity.

The 18% productivity boost observed means the solar array is delivering that much more energy to the grid than it would have if left uncleaned. In effect, daily cleaning added the equivalent of ~13–18% more sunshine hours to each day. Such a gain is especially impactful for commercial operators – it directly improves the energy sales or savings from the PV system without adding new panels. Over a year, an 18% increase in output can significantly lift the project’s revenue and yield profile.

Beyond the raw production numbers, the pilot confirmed several qualitative benefits. The cleaning was performed automatically at night, so there was zero disruption to daytime generation. Unlike manual cleaning crews, the robot did not require the system to be turned off or any sections to be taken offline; it worked during non-production hours, ensuring maximum uptime. The water-based cleaning proved gentle and effective – panel surfaces were visibly cleaner, and an independent lab test has shown that Solaris’s cleaning method causes no adverse effect on panel coatings or performance even after 25 years’ worth of cleanings. This addresses a common concern that frequent cleaning might damage panels; in this case, the data and testing indicate it’s both safe and highly beneficial.

Analysis and ROI

Energy Revenue Gains: For the Demo installation, an 18% output increase translates to substantial financial upside. To put it in perspective, consider a hypothetical commercial solar site with annual energy production worth $566,000 (as was modeled in Solaris’s analysis for a ~3 MW system). An 18% boost would add roughly $100,000 in additional energy revenue per year. Even a more conservative improvement of ~13% was projected to add about $73,600 in annual output value for such a system. This extra revenue directly improves the site’s return on investment.

Cost Savings vs. Manual Cleaning: Automating the cleaning process also yields O&M cost savings. Manual cleaning is labor-intensive, often requiring hiring specialized crews or using equipment like cranes, which can be expensive and infrequent. With Solaris’s solution, once the robot is installed, daily cleaning happens with negligible labor input – operators just monitor through a web portal or app. Over time, this can reduce or even eliminate the recurring expense of manual cleanings. There are also indirect savings: cleaner panels mean fewer performance issues and potentially longer panel life (as hotspots from dirt are mitigated). The Solaris system’s design further keeps costs down by using no on-site electricity and very little water per cleaning, which is important in water-scarce regions.

Total Cost of Ownership (TCO): One of Solaris Hydrobotics’ key value propositions is its low total cost of ownership for PV cleaning. The robot hardware is modular and built for durability, rated for a decade of operation. Maintenance needs are minimal – the water-driven motor has few moving parts and has proven reliable in over 100,000 installations (a technology adapted from agricultural irrigation). With no costly power infrastructure and an affordable unit price, Solaris’s solution is financially accessible even for smaller solar installations (50 kW and up). In the pilot, only a single robot was used; scaling up to cover the whole Demo site would involve multiple robots (one per panel row, or a robot that can be moved between rows). Solaris’s economic analysis for a full commercial deployment shows a compelling payback: for instance, outfitting a site with 35 robots was estimated at ~$367k, which combined with energy gains and operational savings yielded a ~3.4 year ROI. This ROI can be even faster in high-soiling locations or with higher energy tariffs. Essentially, the capital investment in robotic cleaners can pay for itself in roughly 3–4 years, after which the continued energy gains are pure profit for the asset owner.

Customer Impact: For the Demo site owner, the pilot’s success means their facility is now running closer to its optimal output. In practical terms, the site is generating more kilowatt-hours without any expansion – a direct efficiency improvement. This boosts the site’s revenue (or savings, if it’s behind-the-meter) and improves performance ratios reported to stakeholders. The autonomous operation also improves safety and convenience: no more sending maintenance crews onto roofs or arrays for routine cleaning, which can be hazardous and disruptive. The staff can redirect their time to higher-value activities rather than cleaning tasks. Moreover, regular cleaning helps protect the panels from long-term degradation due to soiling and heat spots, potentially extending the asset’s life. In summary, the robotic solution delivered both immediate financial gains and long-term asset management benefits.

Conclusion

The Demo pilot clearly demonstrates the strategic value of Solaris Hydrobotics’ autonomous cleaning technology in a real-world setting. By achieving an ~18% increase in energy output, the Solaris robot turned a chronic operational challenge – panel soiling – into an opportunity for improved performance and profit. The case study highlights a few key takeaways for the solar industry:

• Proactive O&M Pays Off: Regular cleaning can unlock significant energy that would otherwise be lost to dirt. Automated solutions make this feasible on a daily basis, far beyond the frequency of manual cleaning.
• Innovation Lowers TCO: Solaris’s water-powered robot shows that advanced technology can be cost-effective. Its autonomous, electricity-free design minimizes ongoing costs and offers one of the lowest TCO cleaning solutions on the market. The quick ROI observed at Demo suggests that such investments are financially sound for many projects.
• Scalability and Adaptability: The solution works on various types of installations – from ground-mounted farms to commercial rooftops – and can be scaled by deploying multiple robots. It’s also flexible (wet or dry cleaning modes) to suit different environments, making it broadly applicable.
• Enhanced Sustainability and Safety: Automating cleaning reduces the need for manpower, cuts water waste through efficient low-pressure use, and avoids harsh chemicals. It also keeps workers off high roofs and solar structures, improving safety. By keeping panels clean, it maximizes the clean energy output of solar farms, contributing more to renewable energy goals.

Solaris Hydrobotics’ Demo success story blends pragmatic operational improvements with innovative engineering. For O&M professionals and solar asset owners, it provides a convincing example of how adopting autonomous robotic cleaners can improve performance metrics and financial returns. As the solar industry continues to grow, solutions like this will play a crucial role in ensuring that each installed panel delivers its maximum potential over its lifetime. The result at Demo – an 18% boost in productivity – is not just a one-off win, but a glimpse into the future of solar maintenance: smarter, safer, and significantly more efficient.