When a client compares two LED screen quotes, they look at one line: the price. That makes sense. It is also the best way to get it wrong.
Because a façade or roadside screen is not a purchase. It is a subscription. You pay for the hardware once, and you pay for the electricity for eight years. Over that period, the second line can weigh more than the first.
What a screen really consumes
An outdoor LED screen consumes between 350 and 500 watts per square metre in average use, and up to 800 W/m² at peak, i.e. on full white at maximum brightness. Average consumption is typically 30 to 60% of peak, depending on the content displayed.
Let's take a real-world case. A 10 m² screen, the kind of format we install at the roadside.
- Surface area: 10 m²
- Average consumption, conventional SMD technology: 350 W/m²
- Operation: 16 h/day, 365 days
- Price per kWh in Belgium, all-in: €0.30
The calculation:
10 m² × 350 W = 3.5 kW
3.5 kW × 5,840 hours = 20,440 kWh per year
20,440 kWh × €0.30 = €6,132 of electricity per year
Six thousand euros. Every year. For a single 10 m² screen.
Over an eight-year lifespan, that comes to €49,056 of electricity. For many installations, that is more than the purchase price of the screen.
Where technology changes the equation
Traditional screens use individually encapsulated LEDs, mounted on the surface of the board. COB technology mounts the chips directly on the board, without an intermediate package, then embeds the whole assembly in resin. It sounds like a minor detail. It isn't.
Without a package, heat dissipates much better into the substrate. A screen that runs cooler needs less current to produce the same brightness. Manufacturers broadly agree that the difference is 20 to 30% lower consumption at equivalent brightness.
Let's take the same 10 m² screen, with a cautious 25% difference:
- Annual consumption: 20,440 kWh conventional, 15,330 kWh COB
- Annual bill: €6,132 conventional, €4,599 COB
- Saving: €1,533 per year
- Over 8 years: €12,264
The threshold that decides for you
Here is the question that replaces “which one is cheapest”:
Is the extra purchase cost of COB less than €12,000 on this screen?
If so, COB is the cheaper option. Not the more expensive one. The cheaper one, just not at the same moment.
This threshold is not universal. It moves with four variables, and they are the only ones that count:
- Surface area. The larger the screen, the bigger the saving and the higher the threshold.
- Broadcasting hours. A roadside screen switched on 16 hours a day is not a trade show screen that comes out six weekends a year. For event rental, the energy argument does not hold.
- The price per kWh. At €0.30, this is the calculation. At €0.40, the saving over eight years rises to more than €16,000.
- How long you keep it. If you sell after three years, you only recover part of it.
Two warnings, because I prefer to be clear
On manufacturers' figures. Some manufacturers claim savings of up to 50% by combining COB with smart brightness control based on content. That is possible, but it is a manufacturer's figure, measured under their conditions. The verifiable market consensus remains 20 to 30%. I deliberately based the calculation above on 25%. If your supplier claims better, ask them for the measurement, not the brochure.
On my assumptions. The 350 W/m², the 16 hours, the €0.30: these are working assumptions, not your situation. Your electricity contract, your actual hours and the data sheet of the proposed panel will give a different result. The calculation stays the same; only the numbers change.
What to ask your supplier
Three questions, in this order. They will stop you comparing quotes that cannot be compared.
- What is the average consumption in W/m², not just the maximum consumption? Many data sheets only show the peak, which never occurs in real use.
- At what brightness is this value measured? A screen measured at 3,000 nits and a screen measured at 5,000 nits are not playing the same game.
- What is the price difference between your conventional version and your COB version, for the same surface area and pitch? It is the only figure that lets you decide.
And if a partner hosts the screen
In the roadside advertising model, the screen is installed at a retailer's premises, and the retailer provides the power supply. So they are the one paying for the electricity.
Dividing their electricity bill by three or four is no longer a technical detail. It is an argument for signing, and above all an argument for renewing. A partner whose screen costs little to run is not looking to get rid of it after two years.
In this business, energy efficiency is not an environmental argument. It is an argument for a lasting business relationship.
Do you have a fixed screen project?
Send me the planned surface area, the expected broadcasting hours and your electricity rate. I will send you back a costed comparison of the two technologies over their full lifespan. No commitment, and no brochure.
Pierre Duquesne, Proxiled
+32 479 75 13 73
proxiled@gmail.com