Inside the World’s First Hectare-Scale Spectral-Filtering Solar Installation: Highlights from the Voltiris Grower Day

Voltiris welcomed more than 40 greenhouse growers from across Europe to Meier Gemüse in Rütihof, Switzerland, for an in-depth look at the future of greenhouse energy.

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The Grower Day offered a unique opportunity to experience the world’s first hectare-scale installation of spectral-filtering solar modules in full commercial operation — nearly 2,000 Voltiris modules deployed over an entire hectare of cherry tomatoes. For many attendees, it was the first time seeing spectral-filtering solar technology at such scale, operating seamlessly within a high-performing crop system. And the message that resonated throughout the day was simple and clear: renewable energy production and strong crop yields can go hand-in-hand.

Renewable Energy Without Compromise

The event opened with presentations from the Voltiris team and from Ruedi Meier, owner of Meier Gemüse, who shared the first results from the installation. The numbers speak for themselves:

• Up to 1 MWh of renewable electricity produced per day

• Stable tomato production, with a +1% yield increase compared to the reference greenhouse compartment

• Leaf temperatures reduced by an average of 3°C during sunny periods

• 74% of the time spent within the optimal crop temperature range of 20–25°C, compared to 57% in the reference

• Plant temperatures rarely exceeding 28°C, helping safeguard pollination and fruit set

• ~35% reduction in summer grid electricity use

These results confirm what Voltiris set out to prove: that high-performing solar technology can be integrated directly into greenhouse roofs without sacrificing production — and in some cases, even improving it.

A Smooth Path to Integration

Growers were particularly interested in the installation process: how long it took, how disruptive it was, and how easily it could be scaled. At Meier Gemüse, the installation of nearly 2,000 modules was completed within four weeks in May — all while the greenhouse remained fully operational. “I was able to peacefully work from my office during the installation period, which says it all,” Ruedi Meier remarked.

This smooth integration has already translated into daily practical advantages. During the summer, Meier’s harvesting teams opted to work under the Voltiris modules during the hottest hours of the day, benefitting from noticeably cooler conditions.

Seeing Is Believing: The Greenhouse Tour

The highlight for many guests was the guided tour through the greenhouse. Walking under the modules, observing the light environment, and inspecting the tomato plants firsthand offered growers a real sense of how seamlessly the technology fits into day-to-day production.

“Seeing the large-scale installation really shows how well the system adapts to light capture — it’s very clever and easy to install,” noted Charlène Richard-Breyne, Head of the Energy Division at Cerafel, Prince de Bretagne.

The tour also sparked open and lively conversations among growers from Switzerland, Germany, the Netherlands, France, and the UK — many of whom are navigating similar challenges in energy costs, climate-driven weather extremes, and the need for resilient production systems.

A Clear Path Toward a More Resilient Future

For many attendees, Voltiris represents a new kind of opportunity: one that strengthens both energy autonomy and crop resilience.

“We’re looking to move away from carbon-based energy, and switch to other forms. My goal is to run my greenhouse as ecologically as possible, and that means finding new renewable energy technologies like Voltiris,” said Philippe Magnin, a 6-hectare tomato and cucumber grower from the Geneva area.

As global energy markets fluctuate and climate conditions become increasingly unpredictable, greenhouse growers are searching for solutions that provide stability without compromising performance. The Meier Gemüse site now serves as a powerful, real-world example of how integrated solar generation and high-value crop cultivation can reinforce one another.

Following the Grower Day, several participants have already initiated discussions for commercial projects — a strong signal that the industry is ready to scale spectral-filtering solar technology across Europe.

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