Is Hail Now the Biggest Threat to Solar Projects?

Hail is no longer a background risk for utility-scale solar; it's the leading cause of financial loss across the entire PV industry. The gap between what the sector has built and what the environment is now throwing at it is getting harder to ignore.

The numbers tell part of the story. Industry reports have elevated hail to the number one source of financial loss for PV projects, and the trend is accelerating. But statistics alone don't capture what this actually looks like on the ground: arrays running at 30% of expected production, insurance claims that unravel months after a storm, and electroluminescence scans revealing cell fractures invisible to the naked eye.

Martin Pochtaruk, CEO of Canadian module maker Heliene, encountered this reality firsthand over a decade ago. A customer reported that output from one of their arrays had been holding steady — until it wasn't. A wind event hit, and production cratered. "We investigated as part of the insurance claim what had happened to our modules," Pochtaruk told *pv magazine USA*. "Electroluminescence scans of the modules showed cracks in the cells." Heliene's practice of imaging modules before shipment meant they could prove the damage happened in the field, not at the factory. That documentation mattered. But the deeper lesson wasn't about claims management; it was about physics.

Why the Industry Walked Into This Problem

The origin of hail as an underappreciated risk isn't mysterious; it's geographic.

The first major utility-scale solar deployments in the U.S. went up in California and Arizona — places with exceptional solar resources and relatively low hail exposure. The logic made sense at the time. Renewable portfolio standards in California were creating demand, and developers followed the sun. As Brian Grenko, president and CEO of engineering firm VDE Americas, put it: "We started building utility-scale projects in locations like Southern California and Arizona and west of the Rockies generally where, comparatively speaking, the hail risk is low."

The industry optimized its modules and its risk models for the climates it was building in — not the climates it would eventually expand into.

That worked fine for a while. Module prices were falling, balance of system costs were dropping, and hail damage in the desert Southwest was a manageable exception. Front glass thickness became a casualty of cost optimization as manufacturers competed aggressively on price. Then the build-out moved east — into Texas, into the Midwest, into the hail belt.

The solar industry brought assumptions forged in the Mojave into environments where golf-ball-sized hail is a seasonal fact of life. The results have been expensive.

The Physics of the Problem — and a Compounding Factor Nobody Talks About Enough

Here's where it gets structurally ugly. When severe weather approaches a solar installation with single-axis trackers, the standard stow response is to rotate the panels to a near-horizontal position — essentially flat to the ground. This minimizes wind load on the tracker assembly, preventing the structure from acting like a massive sail. Smart engineering for wind. Terrible engineering for hail.

A panel lying nearly flat to the ground is maximally exposed to ice falling from directly above. The same protective posture that saves the racking system turns every module into a target.

You've engineered away one risk and dramatically increased your exposure to another — sometimes within the same storm.

Engineering firms like VDE Americas are working with tracker manufacturers and meteorologists to develop more sophisticated storm response models — dynamic stow modes that weigh wind load against hail trajectory, angle modules to deflect rather than absorb impact, and respond in real time to changing conditions. This is genuinely promising work. But it also highlights how much operational complexity the industry has introduced by treating hail as an afterthought at the design stage.

What Hail-Resistant Design Actually Looks Like

The most durable answer to hail risk starts before a module ships — in material selection, testing protocols, and the willingness to invest in R&D that doesn't have an immediate commercial payoff.

Heliene's approach offers a concrete example. The company manufactures modules in Minnesota and runs a significant research organization out of its Ontario headquarters — an arrangement that isn't accidental. The Canadian federal government offers a 35% investment tax credit for R&D spending, which Pochtaruk says enables Heliene to conduct the kind of extensive, sometimes destructive testing that builds real performance data rather than spec-sheet numbers.

"We collaborate with Sandia National Labs on testing, providing modules for them to use," Pochtaruk said. "In return, we use their mathematical models and validate those with our own destructive testing, which we also share with them." That bidirectional relationship — industry data informing national lab models, lab models validating field results — is exactly the kind of knowledge infrastructure the sector needs more of.

On the hardware side, Heliene uses 3.2mm front glass across its entire product line. That specification reflects a deliberate tradeoff: thick enough to meaningfully resist impact, thin enough not to compromise light transmission or add problematic weight to the module structure. The company also uses aluminum frames, chosen for a balance of structural integrity, weight management, and cost. These aren't exotic choices, but they're consistent ones — and consistency across a product line matters more than optimization on a single SKU when you're trying to make bankable performance claims.

The insider reality here: many manufacturers have treated front glass thickness as a cost lever rather than a performance specification. Shaving fractions of a millimeter off glass to hit a price point made sense when modules were the dominant cost driver and hail claims were rare. That calculus has changed, and manufacturers who built in durability margins are now in a stronger position — both with buyers and with insurers.

The Financial Picture — and What It's Doing to Insurance

Hail damage doesn't just cost money when it happens; it costs money for years afterward in ways that don't always show up in the initial damage assessment.

Micro-cracked cells can continue generating power — just less of it. A plant that takes a hail event may show no immediately obvious damage but produce at 85% of expected output for the next several years. That shortfall compounds across a long-term power purchase agreement. The energy isn't lost in one dramatic moment; it bleeds out slowly, quarter by quarter, against projections that assumed undamaged modules.

This dynamic is reshaping how insurers underwrite solar projects. Carriers are increasingly scrutinizing module specifications, testing certifications, and site-specific hail risk data before issuing policies — and pricing accordingly. Projects in high-risk corridors with thin-glass, budget-spec modules are facing harder markets and higher premiums. Some are finding coverage genuinely difficult to obtain at commercially viable rates.

The insurance feedback loop is actually one of the healthier market signals emerging from this situation. When insurers start pricing risk accurately, developers feel pressure to build more durable projects. When more durable projects get built, actual loss data improves, which allows for more refined underwriting. That's how risk markets are supposed to work — but only if the underlying data is good enough to price from.

What Comes Next

The combination of geographic expansion into higher-risk climates, better storm modeling, insurer pressure, and increased R&D investment is pushing the industry toward a more honest accounting of hail as a structural project risk.

Expect module specifications to become a more contentious part of procurement conversations. Buyers who once focused almost exclusively on watt-per-dollar efficiency are starting to ask harder questions about impact resistance certifications, glass thickness, and frame design. Third-party testing organizations will likely see increased demand for extended impact testing protocols that go beyond current IEC standards — standards that were developed when California desert installations were the reference case.

The projects that get financed most easily over the next decade will be the ones that can demonstrate rigorous hail risk mitigation from site selection through module specification to operational stow protocols. That's not a prediction — it's already becoming visible in how lenders and insurers are structuring their requirements.

The sun belt built the solar industry. The hail belt is going to mature it.

Learn more about how to protect your solar investments at InfraSale Marketplace.

[INTERNAL LINK: hail risk mitigation]

[INTERNAL LINK: solar module specifications]

[INTERNAL LINK: insurance for solar projects]