Make light work of energy savings

Electrical contractors play a vital role in advising customers about how to cut their fuel bills. But what technologies should be your first port of call? When it comes to saving energy in buildings, there is a clear winner on the electrical side – lighting. Rapid advances in LED lamp technology, coupled with the latest controls, are helping building owners and occupiers to lower energy consumption, reduce fuel bills and cut carbon emissions.

LEDs shine on

From streetlights to the domestic sector, there is literally no sector that remains untouched by LED lamp technology. “If you are replacing old T8 and T12 fluorescent lamps with magnetic ballasts with the latest LED technology, you will achieve a payback within two years,” says Wright. “Obviously, the payback will depend on the number of hours that the lighting is on, but in areas with high burn hours this is certainly achievable.”

In new builds, LEDs are a no brainer but Wright does sound a note of caution on refurbishment projects. “If a customer is using modern T5 fluorescent lamps, the most efficient non-LED source, then it’s not worth changing them as the savings won’t be so great.” He also advises paying particular attention to the control gear. “There are a lot of claims made for 50,000 hour lamp life with LEDs, but to get that kind of life from your control gear you are going to have to pay top dollar,” says Wright. “Make sure you pay attention to your specifications.”

As well as massive energy savings, LEDs offer variable colour temperature, from warmer through to cooler whites. This opens up so-called human-centric lighting solutions, which are now gaining traction in applications such as hospitals and offices.

Lighting takes control

No energy-efficient lighting installation is complete without controls. By dimming or switching off lighting when there is nobody in a room, occupancy sensors can reduce electricity use by 30%, says the Carbon Trust. Even more impressive are daylight sensors: adjusting the artificial lighting according to the amount of natural light in a room using daylight sensors or photocells can reduce electricity use by up to 40%.

Yet despite these tried and tested solutions, many businesses are not implementing controls systems because they are often seen as overly technical and complex to operate, according to the Building Research Establishment. This, when coupled with a lack of information on the subject, has resulted in a poor uptake of control technologies and a subsequent failure to significantly reduce the carbon footprint of buildings.

Simple, two-wire bus control systems offer a quick win and overcome many of the obstacles identified by the BRE. Two-wire bus technology significantly simplifies the field level wiring, eliminates expensive wiring home runs and saves money on wiring and installation costs when compared with traditional solutions.

Smart thinking

A potential growth area for electrical contractors is the Internet of Things (IoT) and solutions are starting to appear from smart homes through to high-tech offices. 

In the connected building, lighting offers a lot more than mere illumination. Take the retail sector as an example. The refurbished Carrefour hypermarket in Lille, France has replaced its previous fluorescent lighting with 2.5 km of Philips LED lighting that uses light to transmit a location signal to a shopper’s smartphone, triggering an app to provide location-based services.

The system enables Carrefour to provide new services to its customers, such as helping shoppers to navigate and find promotions across the 7,800 square metre shop floor. In addition, the LED lighting will slash electricity bills by 50%.

All power to PoE

Electrical contractors need to be very aware of what is happening with Power over Ethernet (PoE) technology. This is a potential game-changer in the lighting arena. As luminaires receive both data and power over a single Ethernet connection, typically a Cat 5 cable, there is no need for expensive electrical wiring, reducing installation costs by at least 25%, says Philips, and slashing installation times by 50%.

At The Edge in Amsterdam, the first office building in the world to be equipped with Philips’ PoE technology, each luminaire includes four sensors: one each for detecting light levels, temperature and occupancy (a motion sensor), plus an infrared sensor that serves as emergency control in the event of a power failure. The system is able to provide facilities managers with an integrated view of a building’s occupancy patterns and energy usage. This enables more informed decision making with improved levels of energy and operational efficiency.

WiFi or LiFi?

LED technology opens up the intriguing option of using luminaires to transmit data that can be used in a similar way to Wi-Fi. People are starting to get very excited about VLC and Li-Fi.
Visible light communication (VLC) is the use of the visible light portion of the electromagnetic spectrum to transmit information. This is in contrast to established forms of wireless communication, such as Wi-Fi, which use traditional radio frequency (RF) signals to transmit data. Li-Fi is VLC technology that delivers a high speed, bidirectional, networked and mobile wireless communications in a similar manner to Wi-Fi. 

There are major advantages when using Li-Fi: security, safety and bandwidth. As light does not penetrate opaque materials, the signal can be confined and restricted, which improves security. Also, there is no EMC interference, so you can use Li-Fi safely where Wi-Fi cannot be used, for example in hospitals, in X-ray zones or MRI rooms.
The visible light spectrum is 10,000 times greater than the RF spectrum used in Wi-Fi, and Li-Fi can achieve about 1000 times the data density of Wi-Fi because visible light can be well contained in a tight illumination area, whereas RF tends to spread out and cause interference.