Project: R&J Invest – LED high bays

R&J Invest replaced the 12 mercury vapour lamps of 400W in its 600 m² storage hall in Peer (Belgium) with 12 LED high bays 150W. The light on the floor more than doubled from 160 to 340 lux, while the power for lighting dropped by 62.5%.

Project facts

Client	R&J Invest
Location	Peer, Belgium
Building	Storage hall, approx. 600 m²
Completed	2023
Old lighting	12 × 400W mercury vapour
New lighting	12 × LED high bay 150W
Mounting	10 m, suspended on chains
Illuminance	160 lux before, 340 lux after
Planning	DIALux light study

The starting point

R&J Invest uses its hall in Peer for storage: vehicles, machinery, materials and shelving spread over around 600 m². The hall was lit by 12 mercury vapour lamps of 400W each, a total of 4,800W.

Too dark and failing lamps

With around 160 lux on the floor, the hall was too dark to find, load and check stored goods comfortably. More and more lamps had failed, and since mercury vapour lamps have been phased out in the EU since 2015, replacements were becoming hard to find.

High consumption for a small hall

4,800W running 2,100 hours a year adds up to 10,080 kWh: more than €3,100 a year for lighting a single storage hall at €0.31/kWh.

The solution

Light study first

Before ordering, we made a DIALux light study of the hall. It showed that the 12 existing light points were enough: replacing each mercury vapour lamp one for one with an LED high bay would more than double the light level.

12 LED high bays 150W at 10 m

All 12 positions now carry an LED high bay 150W, suspended on chains at 10 m between the roof beams. Each one replaces a 400W mercury vapour lamp at less than 40% of the power. With 150 lm/W and a 120° beam, the light spreads evenly over the floor, and IP65 protects against dust and moisture in an unheated storage hall. The high bays are 1-10V dimmable, so dimming can be added later. More on choosing wattage and beam in our LED high bay guide.

LED luminaires used in this project

Energy savings in figures

	Before	After	Difference
Luminaires	12 × 400W mercury vapour	12 × 150W LED high bay	one for one
Connected load	4,800W	1,800W	−62.5%
Load per m²	8.0W/m²	3.0W/m²	−5.0W/m²
Consumption per year	10,080 kWh	3,780 kWh	−6,300 kWh
Electricity cost per year	€3,125	€1,172	−€1,953
CO2 per year	1.5 t	0.6 t	−0.9 t
Average illuminance	160 lux	340 lux	+113%

How we calculated this

• Before: 12 × 400W = 4,800W × 2,100 h = 10,080 kWh per year.
• After: 12 × 150W = 1,800W × 2,100 h = 3,780 kWh per year.
• Cost: 6,300 kWh × €0.31/kWh = €1,953 per year.
• CO2: 6,300 kWh × 0.15 kg/kWh = 0.9 t per year.

Ballast losses of the old mercury vapour lamps are not counted, so the real saving was even higher.

Investment and payback

At current webshop prices, the 12 LED high bays cost €712. Half of the investment was covered by an energy-efficiency subsidy, leaving €356. With €1,953 saved per year, the luminaires paid for themselves in just over two months. Installation is not included in that figure; even with installation, a relighting like this typically pays for itself within the first year.

Calculate the savings for your hall

The calculator below is pre-filled with the R&J Invest figures. Change the values to see what a switch to LED would save in your own building.

The result

• More than twice the light: from 160 to 340 lux across the 600 m² hall.
• 62.5% less power: 1,800W instead of 4,800W for the same 12 light points.
• Instant full light: no warm-up time as with mercury vapour lamps.
• No more failed lamps: no more searching for discontinued mercury vapour lamps.
• Lower running costs: €1,953 less on electricity every year.

Frequently asked questions

Can a 150W LED high bay replace a 400W mercury vapour lamp?

Yes. A mercury vapour lamp produces only around 50 lm/W, and part of that light is lost in the reflector. A 150W LED high bay at 150 lm/W sends its light where it is needed. At R&J Invest the light on the floor more than doubled from 160 to 340 lux, while the power per fitting dropped from 400W to 150W.

Is relighting a small storage hall worth it?

Yes. Even with only 12 light points, this hall saves €1,953 a year. With half of the investment covered by subsidy, the LED high bays paid for themselves in just over two months.

Are LED high bays suitable for an unheated storage hall?

Yes. The high bays used here are IP65 rated, so they are protected against dust and moisture. Unlike mercury vapour lamps, LED gives full light immediately, even in a cold hall.

How was the saving of €1,953 per year calculated?

The old installation drew 4,800W, the new one 1,800W. At 2,100 operating hours a year that is 6,300 kWh less. Multiplied by €0.31/kWh, that gives €1,953 a year. Losses of the old ballasts are not included, so the real saving is higher.

Can you make a free light plan for my storage hall?

Yes. Send us a floor plan or a few photos with the ceiling height. We make a free DIALux light study, work out how many luminaires you need and send a non-binding quote at direct-import prices.