Bi-colour or tunable-white LED lighting does not automatically consume 10–20% more power than a fixed-white fixture.

That kind of blanket percentage sounds precise, but it is not a useful engineering rule.

Power consumption depends on the actual fixture design: LED efficacy, driver architecture, thermal management, selected CCT, dimming level, optical losses and the way the manufacturer chooses to balance output across the tunable-white range.

The right comparison is therefore not “bi-colour versus single-colour” in the abstract. It is how efficiently two specific fixtures turn electrical power into useful light in the configuration you actually need.

Enrico Ripalti
About the author

Enrico Ripalti

Maxima Co-Founder · Creative Director at Cinestudio

Creative director and digital artist working across commercial filmmaking, photography and branded content. Enrico combines practical on-set experience with the development and real-world testing of professional lighting tools at Maxima.

Start with the difference between power, efficacy and output

These three ideas are often mixed together:

  • Power consumption is electrical input, measured in watts.
  • Luminous efficacy describes how much visible light is produced per watt, commonly expressed in lumens per watt.
  • Useful illuminance is the light that actually reaches the subject, measured in lux at a defined distance and beam configuration.

A fixture can consume more watts yet be more efficient. Another can consume fewer watts but deliver less useful light after optics or modifiers.

This is why wattage alone is not a brightness specification.

Why the old “bi-colour uses 10–20% more power” rule is misleading

Tunable-white fixtures typically use at least two white-light channels with different spectral characteristics.

That does not mean both channels are always running at full power at the same time.

The driver may:

  • cross-fade between warm and cool channels;
  • limit total electrical power to a fixed ceiling;
  • allow different power at different CCT settings;
  • reserve headroom to stabilise output;
  • use a more complex multi-channel strategy.

Different manufacturers make different engineering choices.

There is therefore no defensible universal percentage by which a tunable-white fixture must consume more power than a fixed-white one.

Fixed white can be easier to optimise around one operating point

A fixed-white fixture only needs to produce one target white point.

That gives the designer more freedom to optimise:

  • emitter selection;
  • driver behaviour;
  • optics;
  • thermal management;
  • maximum output;
  • efficiency around that one CCT.

This can create excellent efficiency, but it does not mean every fixed-white light is automatically more efficient than every tunable-white light.

Product design still matters more than category labels.

Tunable white trades simplicity for flexibility

A tunable-white fixture has to remain useful across multiple CCT values rather than only one.

That can introduce engineering trade-offs such as:

  • different warm- and cool-channel efficacy;
  • more driver complexity;
  • calibration across multiple operating states;
  • different output behaviour across the CCT range.

The payoff is obvious: one fixture can adapt to changing white-light environments without gels or fixture swaps.

The question is not whether that flexibility is “free”. The question is whether it solves enough workflow friction to justify the architecture.

Why power consumption can change with CCT

Warm and cool white LEDs are not necessarily equally efficient.

As the fixture moves from warm to cool, the balance between channels changes.

Depending on the driver design, this can cause:

  • electrical input to change slightly;
  • optical output to change slightly;
  • both to change;
  • or one to remain relatively stable while the other changes.

None of these behaviours is automatically wrong.

What matters is whether the fixture behaves predictably and whether the available output remains appropriate for the job.

Mid-range CCT does not necessarily mean both channels are using full power

This is another common misconception.

If a fixture is set to 4,500K, that does not mean the warm and cool channels are both running at 100% and the lamp suddenly consumes twice as much power.

In a properly managed system, the driver controls the relative contribution of each channel within the fixture’s electrical limits.

The exact behaviour is product-specific.

Constant power and constant output are different design goals

A manufacturer may choose to keep electrical input relatively constant across the CCT range.

In that case, maximum optical output may vary somewhat as the channel mixture changes.

Another design may manage the channels to keep output more consistent, allowing electrical input to change within defined limits.

These are different engineering strategies.

You cannot infer which one a fixture uses from the word “bi-colour”.

Why warm settings can sometimes be less efficient

Phosphor-converted warm-white LEDs often trade some luminous efficacy for a spectrum containing more longer-wavelength energy.

That can mean a warm setting produces fewer lumens per watt than a cooler setting in some fixtures.

But the size of that difference depends on the actual emitter technology and driver design.

Do not turn that tendency into a universal rule such as “3,200K always consumes more power than 5,600K”.

Colour rendering also belongs in the efficiency discussion

A fixture optimised purely for maximum lumens per watt could sacrifice spectral quality.

Professional photography and cinema lighting often need more than headline efficacy.

The relevant balance may include:

  • CRI and R9;
  • TLCI;
  • Duv;
  • spectral smoothness;
  • camera response;
  • unit-to-unit consistency.

A slightly lower efficacy can be a rational trade-off if the resulting spectrum is more useful for imaging.

Electrical efficiency and photographic efficiency are not the same thing

A fixture may have excellent lumens-per-watt performance but poor beam control for a particular shot.

Another fixture may deliver fewer total lumens yet put more useful lux onto the subject through better optics.

Modifiers complicate the comparison further.

For photography and cinema, the better question is often:

How much useful, controllable light reaches the subject for the electrical power consumed?

Dimming usually reduces power draw — but not always linearly

Reducing a fixture from 100% to 50% output generally reduces electrical consumption.

But the relationship between control percentage, optical output and electrical input is not guaranteed to be perfectly linear.

A display reading 50% does not necessarily mean:

  • exactly half the lux;
  • exactly half the watts;
  • exactly twice the battery runtime.

This is why measured behaviour is more useful than assumptions.

Low-level dimming can be efficient and still be optically poor

A fixture may consume very little power at 1% output while showing:

  • stepping;
  • colour drift;
  • temporal modulation;
  • poor repeatability.

Electrical savings do not automatically mean good low-level performance.

See our guide to low-level dimming quality for the optical side of this problem.

Driver efficiency matters

The LED engine is only part of the system.

The fixture also contains power-conversion electronics that turn mains or battery input into controlled current for the LEDs.

Driver losses become heat.

More efficient power electronics can therefore help reduce:

  • electrical waste;
  • thermal load;
  • battery consumption;
  • cooling demand.

This is one reason modern power-electronics design matters even when two fixtures use similar LED emitters.

Thermal management indirectly affects efficiency

LED performance changes with junction temperature.

A well-designed thermal system helps keep the emitters and electronics within their intended operating range.

That supports:

  • stable output;
  • stable colour;
  • reliable driver operation;
  • repeatable performance over long sessions.

Cooling itself can also consume a small amount of power where fans are used, but judging a fixture by fan wattage alone would miss the larger thermal system.

Battery runtime should be calculated from actual electrical demand

If a fixture is battery-powered, runtime depends on:

  • battery watt-hours;
  • fixture power draw;
  • conversion losses;
  • battery discharge capability;
  • temperature;
  • cut-off voltage;
  • the actual CCT and dimming state if those affect draw.

A first estimate is still:

runtime ≈ battery Wh ÷ fixture W

But real runtime should be verified with the exact fixture-and-battery combination.

For the wider electrical workflow, see our professional LED power-planning guide.

Where Maxima Spectra fits

Maxima Spectra is designed around a compact, battery-first tunable-white workflow.

Its direct V-Mount architecture and onboard battery-performance controls make power behaviour part of the operating workflow rather than an afterthought.

For a mobile user, efficiency is valuable not simply because it lowers electricity cost, but because it can reduce:

  • battery size;
  • number of battery swaps;
  • charger load;
  • system weight;
  • time spent managing power on location.

Where Maxima Rapida fits

Maxima Rapida follows the same compact, direct V-Mount philosophy with a stronger emphasis on rugged location use.

Its power architecture is designed to keep the complete system small while supporting professional output in a portable body.

Its IP54 rating is relevant to location durability, but does not change the electrical principles discussed here and does not mean waterproof.

Why direct battery integration changes the practical meaning of efficiency

Two fixtures with similar wattage can create very different location systems.

If one requires:

  • an external ballast;
  • a separate battery plate;
  • long DC cables;
  • additional mounting hardware;

while another integrates the battery directly, the second may be operationally more efficient even if electrical consumption is similar.

Electrical efficiency is only one part of production efficiency.

Where Maxima 3 and Maxima 6 fit

Maxima 3 and Maxima 6 are fixed 5,600K fixtures.

They illustrate the opposite engineering choice: optimise a professional white-light engine around one daylight operating point rather than making the CCT variable.

Maxima 3 is specified at approximately 270W, while Maxima 6 operates in a substantially higher-output class at approximately 600W.

Those wattage figures describe electrical input, not creative brightness by themselves.

Where Furiosa fits historically

Maxima’s earlier Furiosa platform applied tunable-white control to a much larger high-output architecture.

It is a useful historical example because it shows that “bi-colour” does not imply a particular power class.

Tunable-white systems can be compact and battery-first, or much larger and mains-oriented. The power architecture is a separate design decision.

Does a bi-colour fixture waste half its LEDs at the endpoints?

Not necessarily.

This is another oversimplification.

Some tunable-white systems may not use every channel equally at the extreme ends of the CCT range, but the driver, emitter count and thermal design are engineered around the intended operating envelope.

The meaningful question is not how many physical LEDs appear active. It is whether the fixture provides the required output, colour quality and efficiency at that setting.

Should you choose a fixed-white fixture purely to save power?

Only if the actual product comparison supports that decision.

A fixed-white fixture may be the better tool when:

  • you always work around one CCT;
  • maximum efficiency at that one operating point matters;
  • repeatability is more important than flexibility;
  • gels are acceptable when a different white point is occasionally required.

A tunable-white fixture may be better when:

  • locations change frequently;
  • practical lights vary;
  • the production moves between warm and daylight environments;
  • reducing gels and fixture swaps saves time.

The correct answer depends on workflow, not category ideology.

How should you compare two fixtures for energy efficiency?

Use measurements that refer to the same conditions.

Compare:

  1. electrical input at the chosen setting;
  2. lumens or total output if available;
  3. lux at the same distance;
  4. beam angle or optic;
  5. CCT;
  6. modifier;
  7. colour-rendering requirements;
  8. the complete power system.

Comparing lux from one narrow reflector with lumens from another bare source tells you very little.

What matters for electricity cost in a studio?

For a permanent studio, power consumption can affect:

  • electricity cost;
  • circuit loading;
  • HVAC demand;
  • generator requirements;
  • heat added to the room.

Those effects become more important as fixture count and operating hours increase.

For a small two-light studio, the economic difference between two efficient LED systems may be modest. For a large multi-fixture facility running all day, system efficiency becomes much more significant.

What matters on location?

On location, electrical efficiency often shows up as logistics rather than the electricity bill.

It can determine:

  • how many batteries are required;
  • how heavy the kit becomes;
  • how often the crew stops for swaps;
  • whether a generator is necessary;
  • how large the power distribution needs to be.

This is why high efficiency can be especially valuable in compact professional fixtures.

Common power-consumption myths

  • “Bi-colour always consumes 10–20% more power.” There is no universal percentage.
  • “At the midpoint, both LED arrays run at full power.” Driver behaviour is product-specific.
  • “More watts means more light.” Optical efficiency and beam control matter.
  • “Warm light always uses more electricity.” It can be less efficacious in some designs, but this is not a universal fixture-level rule.
  • “50% dimming means exactly 50% power consumption.” The relationship is not necessarily linear.
  • “Fixed-white is always more efficient than tunable white.” Compare actual products and operating points.

So what are the real power-consumption differences in bi-colour lighting?

They come from engineering choices, not from one fixed penalty attached to tunable white.

LED efficacy, channel balance, driver design, CCT, dimming level, thermal behaviour and optical efficiency all affect the final result.

The right question is not how much extra power bi-colour lighting “must” consume. It is how efficiently a specific fixture produces the light your production actually needs.

If you are comparing Maxima Spectra, Rapida or a fixed-daylight Maxima fixture for a battery or studio workflow, talk with a Maxima specialist about the required CCT range, expected runtime, output level and power infrastructure.

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