Generators and lighting towers in the spotlight

A few years ago, generators made a lot of noise and produced quite a lot of smoke but very little power. Lighting towers consisted of little more than the same generators with a pivoted mast and they spent a large proportion of their time sitting in the yard. But not any more.

Generators are cleaner, quieter and more efficient and most lighting towers now have vertical telescopic (often hydraulic) masts, often with demountable generators that can be hired out as standalone units.

And users are becoming increasingly choosey too. They don’t want to annoy those bordering their sites, but they do want to be seen as being environmentally friendly and, of course, save money. So instead of simply concentrating on the purchase price, buyers are also looking at environmental factors and flexibility, which are fast becoming the new battleground Ð a trend not unnoticed by the manufacturers and hire

One of the biggest potential problems for genset users is noise, which not only affects site workers during the day, but also those living nearby at night or over weekends.

Generator specialist FG Wilson pays so much attention to noise that it has invested in a semi-anechoic cell to perfect what business development manager Ciaran McCarney calls “cost-effective noise reduction”. The firm produces units from 6.8kVA to 2,500KVA, including specials for the rental market, up to 1,250kVA. It is experimenting with hybrids such as putting photovoltaic cells and wind turbines on the casing to cater for low-load demand without having to start the engine. More imminent is a fuel-saving auto-idle system that drops the engine speed from 1,500rpm to about 750rpm when demand falls to zero and returns to full speed the moment demand picks up. “People want power instantly and if you have stopped the engine, it can be 15 seconds before it is back up to speed and synchronised,” says McCarney.

Noise considerations

Noise was also a major consideration for Atlas Copco when designing its new QAS range of portable generator, which spans from 14kVA, to the latest 500kVA model Ð the QAS 500 VOD. Even its biggest model, which is powered by a turbocharged 430kW Volvo engine, has its maximum sound power level kept to 77dB(A).

MacGen’s John Parker agrees that buyers want the environmentally friendly features, but says they are generally unwilling to pay a premium and he finds usability is a bigger attraction. For instance, the company’s lightweight 200kVA generator is under 3t and can be towed by a large van or a pick-up to lower transport costs. Options like GPS/GSM tracking and ‘QuickSync’ synchronisation are retrofittable, meaning the purchaser doesn’t have to pay for them up-front.

At the extreme light end of the market, Honda’s new EU30i generator (3kW or 2.6kW continuous) has a 160cc air-cooled engine and weighs just 35kg. It only imposes 8kg on the suitcase-style handle and its large wheels cope with uneven ground, allowing it to be moved around site by one person. While it is primarily aimed at the leisure market, its portability makes it attractive for powering hand tools on sites and its 5.8-litre tank provides 8hrs running time.

Speedy Hire has risen to the environmental challenge by designing the ‘Emission Buster’ Ð a standalone battery and inverter system that works alongside a generator and takes over when the load is low. This has two main benefits Ð lower noise, emission and fuel consumption, and an uninterruptable power supply for key applications.

The number of batteries varies according to the expected demand (up to 3kW) and they are charged by excess power from the normal site generator. When the site closes down at night, the generator can be switched off and the security systems and guard’s hut run from the Emission Buster. If the demand increases or the batteries run low, the generator automatically takes over and powers the required items, as well as recharging the batteries.

Speedy Power’s Russell James says one customer required a light on top of a tower crane day and night and the site’s 25kVA generator had to run 24/7. “With the Emission Buster to power the light, the generator is switched to automatic and shuts down overnight, but it will re-start if the batteries run low,” he says.

Generator specialist SDMO offers a timer system option on its units from 10kVA to 3,000kVA that allows users to programme start and stop times for each day of the week. “It’s similar to setting your central heating so, for instance, a changing room in a welfare unit might only need heating in the early morning and the afternoon,” says Clive Dix, senior sales manager with SDMO. The company, already one of Europe’s largest genset manufacturers with units starting from 500W, is currently doubling the capacity at one of its French factories.

A relative newcomer is JCB, which entered the generator market three years ago and now has 52 models from 8kVA to 600kVA (including 10 bespoke rental units) and specials to 2,200kVA. Richard Butler, director and general manager of JCB Power Products, sees the strengths of JCB’s offering as its distribution network of 90 dealer depots around the UK and more than 350 mobile service engineers. “We provide a single service solution for the whole generator unit,” he says. The strategy seems to be working as the Power Products division continues to report year-on-year growth.

Green credentials

Earlier this year JCB also entered the lighting tower market with the LT9, which has a 9m hydraulic tower that extends to its full height in 13 seconds. Its green credentials also appear good as the three-cylinder Yanmar engine is said to give ‘industry-leading’ fuel economy using only 1.47lit/hr, meaning its 100lit tank contains enough fuel to run for 68 hours. With 4 x 1,000W halide lamps, the light output is 360,000 lumens and Butler reports “good levels of interest” in the tower.

Paul Hay, international sales manager for Towerlight, says: “Environmentally friendly options are the way the industry is going with solar power charging batteries to run LEDs.” However, he says customers want the illumination levels of the current models but with lower fuel consumption, less noise and fewer exhaust emissions. He says the new technologies don’t currently offer the same lighting levels, but believes the technological challenges will be overcome and hybrid solutions will become commonplace.

Towerlight’s latest offering, The Cube, comes with pallet fork recesses rather than trailer mounted, meaning more units can be transported on a single truck or trailer and so reduces transport costs for large sites. The firm also offers a range of lighting tower chassis onto which a standalone generator is mounted.

One of the long-term innovators in the environmental field has been Taylor Construction Plant (TCP), which has now introduced the Ecolite-P. This uses four 150W high-efficiency ceramic discharge lamps with prisma lenses. While the Ecolite-P’s light output is 25% lower than the traditional metal halides, TCP’s managing director Andrew Barker says the light is better focused in the working area and has a different quality that is suited to the human eye. “We don’t try to replicate midday at midnight, we try to replicate bright moonlight,” he says.

According to Barker, the four ceramic discharge lamps atop the 9.1m hydraulic tower will illuminate an area 30m x 30m to a level as good as four 1,000W halides, but without the glare and light pollution affecting those in the surrounding area. As its power requirement is 85% lower (600W compared with 4kW), the Ecolite-P is fitted with a 3.1kW single-cylinder Hatz engine, which runs for two hours on one litre of diesel and 170 hours on a tank full.

Fellow manufacturer Sandhurst is using a different tack to extend the runtime of its latest TL-90 lighting tower and that is a timing device that automatically starts and stops the tower at pre-set times. So contractors no longer have to choose whether to leave the lights on continuously over the weekend or have somebody travel to the site twice a day to turn them on and off. This adds up to a considerable saving in fuel, pollution, noise emissions, servicing costs and overtime payments.

It has also minimised the size of the road-towable unit while adding outriggers, thereby maximising the number that can go on a truck or trailer without compromising stability in high winds.

Auto-start option

MacGen’s customers also benefit from automation as the company fits an auto-start as standard to its MLT 4 tower and this can be coupled with an optional timer. The towers can also be switched to run from the mains and sites with several units may find it more cost-effective to run them all from a single larger-output generator. One final touch on the MLT 4 is that its 9m mast retracts automatically when the handbrake is released.

Going one step further is Doosan Infracore with its latest V9 light tower, which comes with the option of an automatic start/stop system using either a timer or light sensing unit. By sensing the lighting levels there is no need to repeatedly adjust the timer to reflect the earlier/later evenings or moving the clocks forward or back. It will also switch on the tower if inclement weather dramatically reduces lighting levels during the day. These innovations are not at the expense of operational factors as the 9m hydraulic tower can be fully extended in 10 seconds and withstands winds of up to 100km/h.

Site illumination has now entered the space age with lighting balloons and inflatable towers. For instance, Contech Accessories offers both 2.2m and 4.8m-high inflatable towers that house an 875W metal halide lamp. The smaller unit is designed for internal use, albeit that it won’t have the coverage of the taller tower.

At 95,000 lumens, the light output is around a quarter that of a traditional 4 x 1,000W tower, but Contech’s Phillip Lyons says Luminite towers provide enough light through 360¼ to avoid slips and trips over an area of 8,000m². He says the tower material acts as a diffuser, meaning the light is more even whereas with a traditional tower the illumination covers 150¼ and the lights are so bright that workers have to walk around staring at the ground so as not to be dazzled.

Luminite towers (minus the generator) weigh 25kg, can fit in the boot of a car or van, and take only 17 seconds to set up. Once anchored, the towers can withstand winds up to 70km/h, temperatures as low as -30¼, and are fully weatherproof. Lyons says the purchase price is around half that of a standard tower and the lower power requirement means a smaller generator can be used which consumes only about £8 of fuel each night.