Anyone who’s purchased a fridge, washing machine or similar domestic appliance in recent years will be familiar with the energy efficiency label showing the overall energy rating of the machine. Such labelling is required by law and provides a simple, at-a-glance indicator of whether the device in question will lead to bigger electricity bills, or not.

Oh for such a universal scheme in the world of sheetfed printing presses. Recently, the topic of how power-hungry, or not, various presses are has been batted back and forth between rival manufacturers, leading to claim and counter-claim.

The power consumption issue is certainly a serious one for potential purchasers. Electricity costs are rocketing and suppliers recently announced a raft of price increases for 2011 ranging from 5.3%-9% (see boxout). And the amount of electricity being consumed by a business is a big factor in the carbon footprint calculations for environmental accreditations, and for the Climate Change Levy.

"Six or seven years ago we would have had no questions about this [power consumption]," says Manroland commercial sales manager Adam Robotham. "Now if we’re working on a potential project it’s a big part of it. Margins have come down, so people are looking closely at all the elements of an investment."

Firstly, there’s one very obvious question print bosses need to know the answer to, posed by KBA executive sales director Mark Nixon: "Can they actually pull enough power?"

Cautionary tales
The trade is rife with horror stories about spiralling costs when the power available turns out to be inadequate. If you suddenly find you need to upgrade your electricity infrastructure in order to get your flash new kit into operation, the costs can be crippling. "We’re very fortunate, we’ve got 11,000kVA coming into the factory here, but I’ve heard of one printer having to spend £50,000 upgrading a substation in order to be able to run their presses. You can end up spending tens of thousands of pounds putting cables in," warns Andrew Jones, managing director at Merthyr Tydfil-based Stephens & George.

"Some companies have had to compromise on their press specification because of this very issue," Nixon adds.
There are variances between different press models from the same maker, and from manufacturer to manufacturer. Japanese press suppliers, for example, typically produce equipment that is more economical in its use of power. Why is this the case? "I think it stems from the Japanese culture. Space is at a premium there so they plan things properly, and as a result of that other efficiency things fall into line too," says Neil Handforth, sales and marketing director at Ryobi distributor Apex Digital Graphics.

With the requisite amount of power on tap, is ‘press A’, which on paper ostensibly requires a significantly lower power load than ‘press B’, automatically the best option when it comes to overall power consumption? For potential purchasers the answer is ‘not necessarily’.

No matter where they are made, the latest high-performance, highly automated sheetfed presses have a lot of potentially power-hungry bells and whistles on them, with perhaps the most high-profile example being Heidelberg’s XL range.
Competitors have been quick to highlight this as an issue, leading to changes in the way the manufacturer communicates its specifications.

"Heidelberg was initially very careful when it came to providing power consumption details to be absolutely on the safe side, and in order to allow for peaks of utilisation – for example immediately switching on everything at the same time," explains B1 product manager Gernot Keller. "Now we have a lot of XL installations we can see what the actual usage is. Previously it was based on a mathematical model, now it’s based on what’s required from a practical point of view."

Cost per sheet
His colleague Matt Rockley, Keller’s equivalent for B2 and B3, adds: "If you really want to measure like-for-like power consumption it needs to be independently monitored by someone like NoWatt. There’s a very popular misconception about the fuse rating on the XL 75, because some competing machines have a rating that is one-third less. But that doesn’t mean they use a third less power. We have customers producing £4m of turnover on an XL 75, compared to half that amount on B2 machines using older technology. So the only real way to analyse how much power is being consumed is to break it down into cost per copy."

This cost per copy analysis is one area where manufacturers are in accord. "I honestly think you’ve got to look at it in terms of power used per 1,000 saleable sheets produced. Otherwise you can’t make any comparison," says Komori Europe marketing manager Philip Dunn. Manroland’s Robotham concurs: "The best way to compare machine-to-machine is power consumption per sheet. Of course it will vary depending on the job, but you can work it out as an average."

The power consumption analysis extends beyond the actual press itself, and the ancillaries used can make a major difference to the power being consumed. 

"Customers should also consider more energy-efficient peripherals, such as using brush-free motors and water-cooled ancillaries," says Heidelberg’s Keller. "We are fighting to get people to accept water-cooled. People are afraid of the initial investment, but once it’s in it’s a very clean and simple way of cooling and customers just love it. There’s less air turbulence, and fewer filters to clean, so you also reduce the amount of ongoing maintenance required."

Pumps and driers are another power-hungry area for consideration, according to Robotham. "The pumps used in the cabinets alongside our presses used to produce 100% of blast or suction air. Now, the pumps can be frequency controlled with our SelectAir option, so they only produce as little or as much air as needed. Whether that’s 40% or 80%, it will be tuned," he explains. "These options, such as water-cooled peripherals, are a capital cost at the outset, as are frequency controlled pumps, but over the life of the machine you will be saving energy so it’s got to be looked at from that return on investment perspective. That’s the biggest difference, really, looking at the bigger, holistic, long-term picture."

And once potential purchasers start looking seriously at ways to make ongoing savings on power use, the items for consideration keep mounting up. "It’s also worth looking at things like autowash systems," notes Handforth. "We use a non-solvent pre-impregnated towel, whereas normally there’s a tank of solution being pumped – so a pre-impregnated system doesn’t need that pump running. Drying systems are another important area. Baldwin seems to be quite ahead of the game in lower consumption on driers. And for example with a coating unit you would always specify an infrared drier. But on some jobs the drier doesn’t have to be turned on, in some cases the air knives alone will do the job."

Hot topic
Driers are the number one villain when it comes to unnecessary and excessive power use, according to Allister Mannion, development director at energy monitoring and management specialist NoWatt. His top tip is that printers should not automatically use their driers, and when they do use them they should ensure they are on the minimum setting required. "Driers can at least triple the energy costs per job," he warns.

Another important area for scrutiny is that of equipment being left on standby. One NoWatt customer found himself horrified at the amount of power still being drawn by his factory out of working hours. "Lots of print shops with existing kit have demonstrated that staff are leaving kit on standby because it’s easier for the operators. But it might be consuming more power than necessary as a result," says Mannion.

Retford-based RCS has examined this issue in detail, and has come to a possibly surprising conclusion about optimum standby times. "We’ve done quite a lot of work on education of the individual. When people are at home they will diligently turn the lights off, whereas at work it’s not their bill anymore," states managing director Michael Todd. "But if people want wage increases and stability, these are the sort of costs we need to be on top of. We’ve worked out that if a piece of kit is not being used for more than 10 minutes, then it’s better to power it down."

RCS has also installed a PowerPerfector voltage power optimisation system, which allows businesses to ‘micro-manage’ their power supply by optimising the difference between the voltage received on-site, and the voltage actually required by kit. It also eliminates transient spikes in supply from the grid. As a result RCS has reduced its power consumption by nearly 12%.

"Energy is going up massively, some of the projections we’ve seen for the next six years show increases of as much as 40%" concludes KBA’s Nixon. "If that’s the case it’s going to play a very big part in the ongoing usage costs of a product."

RECENT ELECTRICITY PRICE RISES
E.on February, 9%
Scottish Power November 2010, 8.9%
EDF Energy from March, 7.5%
British Gas December 2010, 7%
Npower January, 5.1%

TOP TIPS
• Look at average power costs per 1,000 saleable sheets as part of your investment criteria
• Cut back on unnecessary use or over-use of driers
• Check whether machines are being left on standby for extended periods
• Take a longer-term view and consider investing in more power-efficient ancillaries, such as water-cooled
• If your annual electricity bill exceeds £50,000, a NoWatt system may be beneficial
• Investigate the potential benefits of a PowerPerfector if your power costs are £20,000 or more