LED Light Engines for Microalgae Photobioreactors
Commercial microalgae cultivation requires a different approach to LED lighting than conventional horticulture.
A plant canopy is illuminated across a relatively well-defined surface. In a photobioreactor, the crop is a moving suspension of photosynthetic cells inside transparent tubes, panels or vessels. Light must pass through the reactor wall and into a culture that continuously absorbs, scatters and redistributes photons.
For this reason, an efficient microalgae lighting system must be designed around reactor geometry, illuminated surface, optical path, culture density and spectrum—not fixture wattage alone.
At Lumistrips, we provide linear and rectangular LED light engines for microalgae photobioreactors, from ready-made flexible LED strips and modules to configurable IP67 light engines and completely customized systems for large PBR installations.
More photons into the culture. Less unnecessary hardware around it.
A Lumistrips light engine typically consists of:
LED strip or LED module + LED driver
Depending on the photobioreactor, it can also include LumProtect IP67 protection, aluminium profiles, optical components, reflectors, cables, connectors and lighting controls.
Rather than positioning conventional high-power grow-light fixtures around the reactor, our approach distributes the LEDs along the geometry of the PBR itself: beside tubular loops, between tube rows or behind flat-panel reactors.
For tubular PBRs in particular, long, relatively low-power LED lines positioned close to the tubes can distribute photons more evenly than a smaller number of concentrated high-power light sources.
Why We Use Distributed Linear Lighting
Tubular PBRs can contain hundreds or thousands of metres of transparent tubing.
This geometry naturally favours a distributed lighting architecture.
Rather than illuminating the tube bank with a limited number of powerful fixtures, linear light engines can place smaller amounts of photon output much closer to the reactor surface and repeat that arrangement throughout the installation.
This can improve:
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Photon utilization
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Surface PPFD uniformity
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Control of peak intensity
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Thermal distribution
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Mechanical integration
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Scalability
The system can then be scaled primarily by repeating an optimized tube + LED geometry.
Once tube diameter, LED distance, target PPFD and illumination geometry have been defined, the required PPF and LED configuration per metre can be repeated throughout the PBR.
That is why the linear metre requirement becomes the guideline for practical design and cost calculator of Lumistrips solutions for tubular photobioreactors.
Ready-Made LED Light Engines for
Small PBR Projects
(up to approximately 1000 m total illuminated tube length)
For laboratory scale-up, pilot production and smaller commercial photobioreactors, our existing flexible LED strips provide a practical way to distribute light along tubular reactors.
The project size refers to the total illuminated PBR tube length, not necessarily the required LED-strip length. The relationship between the two depends on tube diameter, target PPFD, LED-to-tube distance and whether the reactor is illuminated from one or several directions.
Fully Custom LED Light Engines for
Large PBR Projects
(more than approximately 1,000 m total illuminated tube length)
Large installations require designing the complete light engine around the photobioreactor, with the opportunity to optimize the complete relationship between photon output, photon distribution, electrical efficiency, thermal performance, waterproofing and system cost.
For these applications, we develop fully customized linear or rectangular LED light engines.
Our reel-to-reel manufacturing enables long flexible LED products to be developed specifically for the geometry of tubular photobioreactors.
Rather than selecting an existing LED strip and adapting the PBR around it, you can:
Choose the LED Technology
We work with horticultural and general-lighting LEDs from leading manufacturers, including:
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Nichia
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Cree LED
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ams OSRAM
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Lumileds
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Seoul Semiconductor
The LED package can be selected according to the required wavelength, photon efficacy, output, lifetime, thermal characteristics, package dimensions and project budget.
For a large photobioreactor, the most efficient solution may not be the LED with the highest individual output. A greater number of moderately driven LEDs can provide better spatial distribution, lower local intensity peaks and improved thermal conditions along the tube.
Select the Spectrum Strategy
Different groups contain different combinations of chlorophylls, carotenoids, phycobiliproteins and accessory pigments. Spectrum can influence biomass productivity, biochemical composition, pigmentation and stress responses.
Available approaches include:
Red | High photon efficacy and strong photosynthetic absorption | |
White + Red + Blue | A multi-channel system providing independent control over important spectral regions while maintaining useful white light for workers and crop inspection. | |
White | A practical solution for crop growth, visual inspection and comfortable working conditions. White light simplifies the lighting architecture while covering the visible spectrum with a single LED type. | |
Red + Blue | A narrow-spectrum approach for applications in which visual working light is not a priority and the spectral design is intentionally limited to selected red and blue wavelengths. | |
White + Deep red | A white base combined with efficient deep-red photons. The two channels can be operated together or controlled separately, depending on the system design. |
Choose the PCB Construction
The PCB should follow the photobioreactor geometry and power level.
Flexible PCB | Manufactured using our reel-to-reel process for long, lightweight LED strips that can be cut, arranged or integrated into custom structures. | |
Aluminium PCB | Recommended for higher-power linear modules that require an efficient thermal path into an aluminium profile or heatsink. | |
Rigid FR4 PCB | Suitable for large rectangular modules, multi-row matrices and applications in which the LEDs must be distributed over a broad surface. |
Design the
physical format
Different photobioreactors require different LED geometries.
Tubular Photobioreactors are best matched to linear illumination parallel to the tube path.
Flat-Panel Photobioreactors should be treated primarily as illuminated surfaces.
The lighting system is therefore specified in PPF per square metre of panel face, with distributed rectangular modules or parallel LED bars.
Bubble Columns and Airlift Reactors may required vertical linear LED strips arranged around the reactor circumference.
For Bag and Sleeve Reactors, flexible LED strips or vertical lighting bars can follow the long sides of the reactor.
In the case of Biofilm Reactors, as the algae grow on a relatively defined surface, lighting design is closer to conventional top-down crop lighting.
Optical Control Where It Adds Value
Optical design has high value in microalgae lighting.
The curved surface of a tubular PBR can reflect or redirect part of the incident light, while a wide LED beam may send photons between neighbouring tubes rather than into the culture.
Depending on the geometry, we can use:
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Wide or narrow LED optics
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Asymmetric lenses
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Reflectors
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Reflective backing surfaces
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Diffusers
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Close-coupled light guides
The objective is high optical utilization: the percentage of generated photons that actually enter the useful reactor area.
This can allow a lower installed electrical power to produce the same useful photon delivery.
Protection Against Humidity and Water
Photobioreactor lighting can imply potential exposure to:
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High humidity
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Condensation
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Splashing
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Cleaning water
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Saltwater cultures
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Cleaning and disinfecting chemicals
Where the project requires, we can use:
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Aluminium profiles with transparent covers
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Protected housings
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Sealed connectors
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LumProtect IP67 flexible LED technology
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Customized waterproof modules
Protection must be considered together with thermal management and efficacy. Completely sealing an LED system can result in reduced PPF output and heat transfer, so the enclosure and power level need to be engineered as one system.
Profiles and Thermal Management
Close placement improves photon utilization but also places the LED heat source close to the culture.
This matters because microalgae productivity can be highly temperature-dependent.
Aluminium profiles can:
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Transfer heat away from the LED PCB
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Support the light engine mechanically
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Hold optics and covers
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Protect wiring
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Provide mounting points along the PBR frame
For high-output systems, the thermal path should be designed so that LED waste heat is transferred away from the reactor rather than into the culture.
Drivers, Dimming and Lighting Control
Photobioreactors benefit particularly from dimmable lighting.
As the culture becomes denser, the optical environment changes. The lighting requirement during inoculation can therefore differ substantially from the requirement at maximum biomass concentration or during a stress-induction phase.
Available functions can include:
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Central dimming
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Flashing
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Zone control
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Red/blue channel control
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White + colour channel control
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Photoperiod control
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Multi-stage recipes
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Integration with PBR process controllers
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Feedback from light or biomass sensors
Several LED bars can be powered from appropriately selected common drivers, reducing duplicated electronics along long reactor installations.
We desgin the Light Engine to Match the Photobioreactor
Our LED strips, modules and custom light engines can be customized based on
the photobioreactor configuration:
Tubular Photobioreactors
Best matched with long, low-profile linear LED light engines installed parallel to the tubes. LumiFlex or LumProtect strips can be positioned beside individual tubes, between tube rows or on opposite two or four sides for more uniform illumination.
Airlift Reactors
Airlift reactors can use vertical linear LED light engines positioned around the transparent reactor walls. LED spacing and output should account for reactor diameter, internal geometry and the optical path through the circulating culture.
Flat-Panel Photobioreactors
Flat panels are best illuminated with distributed linear strips or rectangular LED modules covering the reactor face. The system should be designed by illuminated area in m², with one-sided or two-sided lighting depending on panel depth and culture density.
Bag Reactors
Flexible bag photobioreactors are well suited to low-profile linear LED strips positioned along one or both broad sides of the bag. The flexible format makes it easier to follow the reactor geometry while keeping the light source close to the culture.
Bubble Columns
Vertical bubble columns benefit from LED strips or bars arranged vertically around the reactor circumference. Several moderate-output light engines can provide more uniform radial illumination than one high-power source.
Thin-Layer Reactors
Thin-layer reactors are well suited to distributed surface lighting with linear LED strips or rectangular LED modules positioned above or behind the shallow culture layer.
From LED PPF to the Light Experienced by the Cells
PPF tells us how many photons the LEDs generate.
Surface PPFD tells us how many photons reach the reactor wall.
Neither measurement alone tells us exactly how much light each microalgae cell experiences.
Inside the PBR, the light field is also influenced by:
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Biomass concentration
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Pigment concentration
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Optical path length
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Tube or panel geometry
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Mixing speed
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Flow pattern
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Light-dark cycling
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Reactor-wall transmission
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Fouling
A dense culture can simultaneously contain cells close to the wall receiving excessive light and cells deeper in the reactor receiving too little.
This is why Lumistrips treats the LED system as one part of the complete photobioreactor optical design.
Info Needed to Design a
PBR Lighting System
1 / Microalgae species or strain
Different species contain different combinations of chlorophylls, carotenoids, phycobiliproteins and accessory pigments.
2 / Spectrum Strategy
Spectrum can influence biomass productivity, biochemical composition, pigmentation and stress responses.
3 / PBR type
Determines whether the lighting geometry should be linear, planar or radial.
4 / Total tube length & diamter
Defines the scale of a tubular photobioreactor project and helps determine total LED requirements and the illuminated surface area and optical path through the culture.
5 / Dimming and spectrum control
Determines the driver architecture, number of channels and control strategy.
6/ Flat-panel dimensions
Defines the illuminated surface area for flat-panel photobioreactors.
7 / Target surface PPFD
Establishes the required photon delivery at the reactor surface.
8 / LED-to-reactor distance
Influences PPFD, uniformity and optical losses.
9 / One- or multi-sided illumination
Changes the required PPF per linear metre and the spatial light distribution.
10 / Humidity and cleaning conditions
Determine the required level of environmental protection, sealing and materials.
One Custom Light Engine, Repeated Across the PBR
For a large tubular PBR, the goal is ultimately to establish an optimized lighting unit cell:
tube diameter + tube spacing + LED position + spectrum + PPF/m + optical control
Once that geometry has been validated, it can be repeated across the complete installation.
Instead of specifying thousands of individual grow-light fixtures, the project can therefore be engineered around a standardized LED light engine per metre of reactor.
This makes it possible to optimize the complete system for photon utilization, PPFD distribution, electrical efficiency, lifetime, waterproofing, installation cost and serviceability—and then reproduce that design across thousands of metres of photobioreactor tubing.
Tell us the microalgae species, tube diameter, total tube length, LED-to-tube distance and target PPFD. We can determine the required PPF per metre, spectrum, LED configuration and lighting architecture for the project.
Contact Our Engineering Team
LUMISTRIPS
Hechingen, Germany
Kwun Tong, Hong Kong
Ramnicu Valcea, Romania
+40.729.850.710