HPS Is Not Disappearing – Why “Mature” Lighting Technologies Still Matter in Modern Greenhouses

Ushio’s participation at HortiContact 26

For several years now, high-pressure sodium (HPS) lighting has repeatedly been labeled a “dying technology.” The narrative is familiar: LEDs are newer, more efficient, more controllable—and therefore assumed to be the inevitable replacement for traditional discharge lighting.

Yet reality inside commercial greenhouses across Europe tells a different story.

As manufacturer of high-quality HPS lamps, we continue to experience strong demand for these products. This includes both 1000 W double-ended HPS lamps for high-intensity supplemental lighting as well as single-ended lamps (400 W, 600 W 750 W), which remain widely used in commercial greenhouses across Europe. In several segments, demand currently even exceeds our expectations.

This ongoing relevance is one of the reasons Ushio will participate once again in HortiContact 26, one of Europe’s leading horticulture trade events.

System-level evaluation remains essential

While LED lighting has become an important part of modern horticulture, lighting decisions cannot be based on efficiency metrics alone. Scientific studies and practical experience show that HPS lighting continues to offer system-level benefits, particularly in greenhouse environments:

• Radiant heat from HPS contributes directly to leaf temperature, influencing transpiration, nutrient uptake, and crop development—particularly in winter and in high-latitude greenhouses.
• The broad spectral output, including red, green/yellow and far-red components, supports canopy penetration and balanced photosynthesis without complex spectral tuning.
• HPS integrates naturally into greenhouse energy systems where lighting heat is part of the overall climate and heating strategy.
• Crop protocols, yield expectations, and climate recipes built around HPS are stable, predictable, and proven.

In addition, high investment costs and long return-on-investment timeframes remain a decisive factor for many growers. Especially where existing HPS installations are still performing reliably, the economic justification for a full technology change is not always given. This reality continues to slow replacement rates, even as new technologies become available.

Differentiation instead of polarization

René Polak, Sales Directore Horticulture Lighting, emphasizes: “The continued use of HPS lighting is not a rejection of LED technology. Both systems have clear strengths and application areas, depending on the type of crop, the climate, and the infrastructure. In recent years, we have seen a increasing number of hybrid solutions combining HPS and LED, offering growers a way to combine efficiency and reliability.”

“Horticultural lighting decisions require careful, fact-based evaluation,” he continues. “In many cases, HPS remains a technically and economically sound solution.”

Visit us at HortiContact 26, Booth E39. We are looking forward to engaging with growers, consultants, and researchers to discuss differentiated, performance-driven approaches to greenhouse lighting.