SOLAR VS HAIL: PIVOTING AWAY FROM DANGER
Nextracker Perspective
Risk Reduction Strategies
Author: Greg Beardsworth, Senior Director, Product Marketing, Nextracker
Successfully reducing risks from hail events depends on effective and reliable hail stowing technology, informed module selection, accurate hail forecasting, and operational preparedness.
Key ingredients of Nextracker’s hail stowing technology and support for system owners and operators include:
Evaluate hail risk early
Hail risk mitigation begins in the project development phase. Nextracker, in collaboration with VDE Americas, provides project-specific hail risk analysis that includes site level damage probabilities for a range of PV module types and tracker stow angles. These projections and data support informed decision-making and smart choices in the technology deployed at the site.
Employ high-angle stowing
The survivability of PV panels depends on three key factors: hail size, glass thickness and tempering, and tracker angle at the time of impact. High-angle stowing creates a glancing blow effect that can make the difference between widespread losses and minimal damage. For projects with low to moderate hail risk, Nextracker deploys NX Horizon trackers with a standard 60-degree stow position. For sites with severe hail risk, NX Horizon Hail Pro-75 offers an even steeper 75-degree stowing angle.
Maximize stow reliability
Every NX Horizon tracker row is powered by a dedicated auxiliary solar panel and supplemented by an integrated backup battery. This de-centralized, self-powered architecture ensures all tracker rows are ready for hail stowing in any scenario, without reliance on grid power. Should external communications to tracker rows be lost, each row will autonomously move to safety stow position after a user-configurable timeout period.
By contrast, AC powered systems risk getting stuck in a vulnerable position while a hail event approaches, due to the potential co-occurrence of hail and power outage. In addition to hail, convective storms often bring high winds, lightning, and flooding, thereby putting utility transmission and distribution equipment at risk.
Engineer for hail and wind
Severe convective storms can deliver both high winds and large hail. To fully address both conditions, NX Horizon is structurally engineered to stow at its maximum rotation angle for both wind and hail events. Hard stops at every foundation pile limit movement beyond the designed angle, providing extra stability when in the stow position. Additionally, NX Horizon trackers in hail regions are engineered to withstand the wind from all directions, to support any hail stowing strategy and address potential changes in wind direction with confidence.
Minimize operator workload
As potential hailstorms approach, well-designed software helps operators act quickly. NX Navigator™ provides a simple, intuitive interface that directly integrates with NX Horizon’s hardware and firmware. A “one-click” site-wide command enables rapid hail stow execution. Optional automated hail stowing utilizes third-party weather forecasts and user configurable stow triggers, further easing operator burden. Nextracker provides regular training and collaborates with customers to continuously enhance NX Navigator’s feature set.
Ensure stow readiness
NX Navigator empowers owners and operators to monitor system vitals and proactively and maintain stow readiness. Tracker data is continuously monitored, aggregated, and presented in simple terms. Nextracker recommends sitewide hail stow testing once per month and has developed a test procedure used to confirm that the entire ecosystem—technology, people, and processes—performs as expected. In addition to standard training, Nextracker offers a range of monitoring and hail-readiness support services for owners, operators, and their staff.
Establish closed-loop learning
Following every hail stow event, success metrics are automatically measured and reported via NX Navigator, giving operators prompt and useful feedback. These stow reports inform analysis, guide targeted maintenance, and provide a basis for follow up if needed. Stow reports also support future insurance submissions. This comprehensive approach enables owners and operators to engage in closed loop learning and enhance operational excellence for every power plant in hail risk areas.
From Risk to Resilience
Recent utility-scale solar hail losses have underscored the need for comprehensive improvements to hail risk mitigation, including better technology, forecasting and operations. The industry is evolving. Owners are enhancing existing plants with improved procedures, forecasting tools, and software upgrades. Developers are choosing high-angle stowing trackers and stronger modules for upcoming projects.
In Texas, much of the upcoming buildout will feature NX Horizon Hail Pro-75. As these sites go live, expect reports of significant hail events with no meaningful damage. With accurate site assessments, better tools, and disciplined execution, the industry is meeting the hail challenge and enabling smart solar growth in storm-prone regions.
