For many years, High Pressure Sodium (HPS) lights were the most commonly used type of lighting in ports and terminals. HPS lights give an ‘amber’ looking feel to a port or terminal and were introduced to replace the good old incandescent lights which consumed more electricity compared to HPS lights.
With new developments, technology advances and market demand new light solutions entered the market to further reduce power consumption during for example night operations. A couple of years ago, Light Emitting Diodes or LED lights were introduced and became the new trend with numerous applications – you will find them around the house and perhaps they are even fitted on your car!
LED lights were cheap and use far less electricity compared to the HPS fixtures. Energy consumption and costs can account for up to 60% of a port’s operating expenses. Continuously rising energy costs are weighing on terminal and port operators hence the popularity of the use of LED lights. Even Philips, the world’s biggest lighting maker, reported a 38% jump in first quarter LED sales from a year earlier.
New kid on the block
But there is a new player in the market – Light Emitting Plasma (LEP). Both LEP and LED provide similar reliability and lifetime – for example LEP technology has been in use for several years in theatre applications.
In the present market, there are many efficient lighting systems for terminals applications such as Yard (high mast) and Container Handling Cranes (RTGs, QCs, ARMGCs, etc.). The most commonly used type of light is the LEDs and perhaps the upcoming LEPs. There are similarities between both types of lightings. Their technology is in the emitting source whereas another light technology on the market – the Prismalence core technology – is using a Prismatic lens, incorporating a Ceramic Discharge Metal halide (CDM) HID bulb, electronic ballast and product design which helps to further reduce power consumption in an overall aspect.
HPS versus HID fixtures
Perhaps we should take a step back and look at high-pressure sodium (HPS) fixtures. Virtually all terminals around the world are equipped with HPS fixtures mounted on high-mast light towers. These are typically “1000W” fixtures with a power supply of 480V, rather “noisy” and as a result have high power consumption. The height of the masts range from 80’ to 150’ and the mast spacing is usually on the order of 3 to 3.5 times the pole height. Typically 250’ to 400’ poles have rosettes of 8 to 12 fixtures per mast. The fixture design relies on glowing housing to spread the light, which causes substantial sky glow. According to an unnamed US Terminal Operator it is estimated that the replacement of each mast and foundation costs around USD300 thousand.
As mentioned earlier, in the present market, most of the ‘green lighting’ technology is in the emitting source which requires time to prove on the effectiveness and efficiency. No doubt that there is energy savings on their technology, but the concerns lies on the lifespan and effectiveness on the suited application. According to Singapore-based MEMSCO, Prismalence lens technology uses Philips HID light bulb and gears, which is a common brand and able to source for spare parts through local Philips distributors. With the lenses they are able to use a lower wattage to match a higher wattage light fitting – for example one 150W Prismalence is the equivalent of a 400W HPS light, providing control of the light and project to the working area and reducing light wastage thus achieving saving energy from at least 60% to over 80% depending on application study. Prismalence lights can also be used on container handling cranes and high mast applications. Recently, MEMSCO installed their compact light weight design Prismalence system on container handling cranes (a quay crane & RTG) at the Laem Chabang Container Terminal in Thailand achieving energy savings, brighter working environment, improved night vision with ‘natural daylight’, standardisation of lighting wattage and type (less and ease of maintenance) and diesel savings for the RTGs.
LED Lights
The use of LED lights in ports and terminals around the globe has seen a jump in popularity simply due to the huge reduction on electricity consumption. “The directionality of LED light is good and the properly balanced high-end LED fixtures are beginning to achieve satisfactory CRI and colour temperatures, although this comes at a significant premium,” according to a spokesperson for MEMSCO. “Lumen density of LEDs is still low compared with Plasma. It still takes about 100 typical high lumen LEDs to produce similar lumen output to 1 Plasma source. This high component count combined with high thermal sensitivity which requires large heat sinks yields fixtures which are typically larger, heavier, and more expensive than a Plasma fixture for the same lumen output. LED lights do have the advantage of ‘instantaneous turn on’ therefore LED lights are a good fit for lower lumen applications such residential indoor and accent lighting, but not high-lumen applications.” But according to a leading port engineer to create sufficient and proper spreading of light, a large array of individual LEDs is required. It is suggested that the array needs to be on a large, curved surface as LEDs generate a good deal of heat, and are sensitive to overheating. It is also recommended that large heat-sinks are applied, with fans or heat exchangers. Properly-designed LED heads are heavier than HPS fixtures and still create “hot spots” of bright light on the ground.
But despite all this LED lights have a significant lifespan, lasting between 50,000 to 100,000 hours, making non-scheduled equipment downtime due to lamp failure non-existent. The life time of HPS lights are far less – about 2,000-20,000 hours. According to US-based Phoenix Products Company Inc another important advantage to LED fixtures is their durability. LEDs are solid state devices containing no moving parts, no filaments or fragile glass to break, thereby eliminating the risk of damage during transportation, installation and operation, even in the toughest environments, such as on port cranes that produce a lot of vibration.
“Terminals can consider programming their LED floodlights on ASC trolleys and girders to remain off during normal operation. This achieves even greater energy reduction and less light pollution,” said a spokesperson for Phoenix. “LED lights are instantly at full intensity, and the on/off cycles have no negative impact on expected lifespan. LED luminaires are also advantageous for ship-to-shore (STS) cranes. They often experience power outages, and operators need to wait time up to 20 minutes for traditional lighting fixtures to warm and return to full intensity. LED fixtures minimise downtime and improve overall efficiency.”
Phoenix Products Company was selected by the Long Beach Container Terminal (LBCT) in California, USA to outfit new cranes with LED lighting. In pursuit of expense reduction and higher environmental standards, LBCT chose Phoenix Products’ ModCom LED flood, walkway, and interior lights for its new ship-to-shore (STS) and automated stacking cranes (ASC). LBCT expects considerable energy usage reductions and cost savings from this investment. Additionally, these LED fixtures will virtually eliminate the routine maintenance that is common with traditional lighting technology, which further reduces costs and increases the overall level of safety. The LED fixtures are uniquely designed for durability and to withstand the consistent vibration and wear and tear of container handling operations as well as the corrosive marine environment. “This project will help LBCT increase its competitiveness by dramatically reducing lighting-related energy consumption and crane maintenance costs,” said Ryan Hertel, Director of Business Development for Phoenix Products.
LBCT crane lighting designers used a combination of 150W and 300W ModCom LED floodlights with customised modular optics to achieve desired light levels in working areas. On the crane exterior, 18W LED fixtures line the walkways to replace traditional fluorescent lighting and eliminate broken lenses, lamps and sockets. Strategically placed fixtures are equipped with an emergency battery backup to illuminate the escape route for the operator. Phoenix Products’ RSL linear LED fixtures also illuminate the interior spaces in the machinery house and electrical room. The traditional placement of these fixtures makes maintenance and lamp replacement difficult, and the LED fixtures will help the terminal avoid these costs. Each operator cab is outfitted with dimmable LED lighting to allow the operator full control over interior light levels. The LED fixtures will help the terminal avoid these costs and hassles. These LBCT cranes are currently being built by Chinese crane manufacturer, ZPMC, with the first cranes expected to arrive toward the end of 2013.
Another company that has been involved in some new LED projects is South Korea-based Yuyang DNU. This might be a new name in the ‘port arena’ but the company has been around since 1976 and is registered on the Korean Stock Exchange. With an annual turnover of over USD137 million and 1300 employees the company lists LG and Samsung as their main clients. Allan Cho, General Manager – Overseas Sales Team at Yuyang DNU reports some interesting projects including that of the Pyeongtaek Container Terminal (a Hanjin Shipping affiliated company) project where they replaced the 1.1kW HPS lights on the light masts (containing 10 light fixtures each) with their own LED flood light series 600W with 51,000 lumen output.
“The new LED Flood Light system (Model No YGI-600A) is light in weight (24kg), simple and compact and provides energy savings up to 60%,” said Cho. “Furthermore the light unit has a long life (not less than 50,000 hrs), excellent heat radiation with heat sink, is easy to install and has low maintenance. Energy savings of 40% can be achieved with this system.”
LEP Lights
Energy consumption savings could also be achieved by using Light Emitting Plasma (LEP) technology. As stated before LEP technology has been in use for several years in theatre applications but despite its success the technology is somewhat ‘unknown’ in ports and terminals. To generate the required light LEP fixtures uses two light emitters which include a double reflector for each emitter – a small reflector below the emitter, bouncing light into a larger reflector above the emitter, spreading the light out. There are some benefits to the use of LEP lights as it limits light pollution and eliminates hot spots on the ground. Unlike HPS or LED, LEPs can be run at 50% power consumption, generating 20% as much light. Unfortunately, the head weighs are similar to that of an HPS head – quite heavy.
US-based Bright Light Systems supplies the BLP1000 which the company claims is the only energy efficient high mast luminaire that utilises Light Emitting Plasma (LEP) to deliver a brilliant white light comparable to daylight with an efficacy that surpasses fluorescent, HID or induction luminaires.
According to John Chalmers, Director of Marketing at Bright Light Systems, Inc their BLP1000 LEP High Mast fixture, which is an energy efficient replacement for 1000W HPS/Metal Halide fixtures consumes only 550 watts and can be paired with a wireless controller that provides power on/off, a dimming control, resulting in even greater energy savings – tests have shown that 10 LEPs are required to provide the same average light intensity as 12 brand-new HPS fixtures (5500 Watts against 12000 Watts). “We currently have installations in 3 major ports in the US,” said Chalmers.
The reduction of electricity consumption and the need to ‘portray’ a greener image might be high on the priority list for many ports and terminals around the globe but there is one piece of information that might be given a lot of consideration when it comes down to terminal lighting. According to a study by the National Institute for Occupational Safety and Health in the USA, the greatest percentage of accidents – 53% – happened during the maintenance and repair work of light fixtures. The longer life and materials (no glass) of LEDs would decrease the exposure to these hazards.