LED tubes (retrofit lamps) are often the fastest and least expensive way to replace old T5 fluorescent tubes. Complete LED luminaires deliver better system efficiency, light quality, controllability, and durability — at a higher upfront cost. Which approach fits your building depends on visual comfort requirements, budget, grant eligibility, and your long-term strategy.
Converting a T5 fluorescent installation to LED is often a worthwhile investment: lower energy consumption, reduced maintenance, and modern control options are common benefits. The two common approaches are replacing the tubes with LED retrofit tubes (LED tubes) or replacing the whole fixture with a dedicated LED luminaire. This article explains the differences, the practical pros and cons of each approach, and the checks you should run before deciding.
LED tubes: Replacement LED tubes that plug into existing fluorescent fixtures. Some types require a ballast bypass (rewiring) while others are designed to work with specific electronic ballasts (EVGs). They are a fast retrofit option but rely on the existing fixture housing and optics.
Complete LED luminaires: New fixtures with integrated LED modules, engineered optics, heat sinks, and electronics. These are designed so the light distribution, thermal management, and control systems work together for optimal performance and lifetime.
LED tubes are a sensible choice when you need a fast, low-cost reduction in energy use and the spaces have low visual comfort requirements — for example garages, technical rooms, gas supply rooms, ancillary spaces, or storage areas with few operating hours.
Complete LED luminaires are the right choice where visual comfort, uniform illuminance, and control matter — offices, production lines, schools, and workplaces. They are more future-proof, easier to integrate with controls (DALI, sensors), and often eligible for grants.
Compare both options using: investment cost, installation effort, system efficiency, kWh savings, lifetime, light quality (CRI, correlated color temperature), controllability, thermal behavior, appearance, grant eligibility, and payback time.
In short: LED tubes are cheaper and faster to deploy. Complete luminaires are more sustainable and provide better lighting outcomes.
Useful reference and funding guidance: Energy Switzerland — Lighting for businesses (energieschweiz.ch)
For consultancy: sensorasmart.com
As a rule of thumb, LED solutions save around 40–60% energy compared with T5 fluorescent systems.
Typical payback times:
Payback depends on electricity price, operating hours, and subsidies. Use measured power, realistic operating hours, and your electricity cost for a reliable business case.
In most cases, no. LED tubes often do not achieve required uniformity and can create glare because the fixture optics are not matched to the directed emission of LED tubes.
With conventional magnetic ballasts (KVG/VVG), rewiring is usually required. For electronic ballasts (EVG), check the LED tube manufacturer’s compatibility list. Often, replacing the complete fixture is the technically safer solution.
Measure illuminance at three to five points per room and check uniformity (min/max ratios) to verify compliance with workplace requirements.
Start with an on-site analysis: fixture inventory, operating hours, and 3–5 illuminance measurements in representative rooms. Based on that, decide whether LED tube retrofits or complete fixture replacement is the better long-term choice.
If you want help with measurements, evaluation, or implementation, contact a lighting designer or consultancy. We’re happy to support you in reviewing your analysis and rollout plan. Book a short, free call here:
Schedule a meeting: https://meetings-eu1.hubspot.com/daniel-fluehmann
Sources & further links:
energieschweiz.ch (Lighting for businesses)
sensorasmart.com
— Dan Flühmann