Many countries have adopted energy labels in the global efforts to reduce environmental effects. They signal to consumers the energy costs they can expect from domestic equipment like washing machines, tumble driers, air conditioners and lamps. In Europe, the EU is also now classifying industrial applications with its EuP (Energy using Products) Directive, in preparation for setting energy reductions around 2012. Before then, though, customers will find it very difficult to compare the performance of industrial manufacturing equipment. Standards like ISO 14000 require reports of environmental effects, and efforts to reduce them. The most important effects in electronics manufacturing come from boards and components. Toxic compounds like arsenic, beryllium, cadmium, copper, and lead are, for example, present in cell phones and displays. Equipment casingsmay incorporate brominated flame retardants. 
Manufacturing lines also consume energy, usually 24 hours a day, with soldering and pick-and-place equipment being the two most energy intensive processes. The energy consumed by soldering is determined by process requirements. A solder oven’s insulation will affect consumption, but the most important factors are the solder’s melting point, length of the oven and the number of temperature zones (heat capacity). Any heat escaping from equipment also has to be removed by HVAC (heating, ventilation and air-conditioning) equipment thus making any energy savings worth double. Equipment design can have the strongest impact on future environmental performance, with downstream effects being spread across millions of products. The design determines the energy consumption, but comparing designs is impossible without standard measurement methods. A popular method is the ‘Eco Indicator 99’, which uses Life Cycle Assessment (LCA). It assigns ‘Eco points’ to represent a product’s total lifetime environmental damage. The steel, aluminum, copper and plastics used in pick-andplace equipment can mostly be recycled, so the major effects come from transport, installation and – particularly – use. Pick-and-place machines normally last seven years or more, therefore energy consumption over the machines’ lifetime is their most significant effect on the environment. In China, particularly, this is important since energy demand is growing faster than supply. Coal plants will meet much of the 30-35 GW per year shortfall, but they are already causing severe environmental pollution, and this can only worsen as the thermal quality of coal drops. So, energy efficiency there is even more urgent. Philips has committed to improving its energy efficiency by 25 percent in 2012 compared to 2007 levels as part of its EcoVision IV programme. As part of this effort, Assembléon used the ‘Eco-Indicator 99’ to assess the major impacts of its pick-and-place machines. These include the electricity they use for driving motors, controls and compressors, as well as the lights and air conditioning for the factory itself. Less obvious, but also significant, is the power taken by reworkstations. LCA for pick-and-place
The LCA tree for a pick-and-place machine (figure 1 shows a simplified version) gives the most significant material and energy flows. The environmental impacts separate out into machine production, use and disposal. Major effects during assembly are associated with steel production as well as road and (particularly) air transport. During use, most important is the energy consumption. Properly designed equipment will be largely recyclable, and so haverelatively low impacts at disposal. 
During use, most energy goes to power the pick-and-place machine and provide compressed air and vacuum. The space around the machine must also be heated/cooled and air conditioned. Assembléon calculated a virtual box around the machine to allow for this. The length is the same as the length of the machine, the depth is the depth of the machine plus 1m operator handling space at each side, and the height is 4m to allow for the height of the factory hall ceiling. At end-of-life disposal, the machine is dismantled. Where possible, the materials arerecycled, and the rest go to landfill. Calculating eco-points and ranking the effects
The ‘Eco-Indicator 99’ method next calculates the damage model for these flows using the three ‘damage categories’ shown in figure 2. Extra energy will in future be needed to extract mineral and fossil fuel resources. Ecotoxicity, acidifi cation, eutrophication, climate change, ozone layer depletion and land use will affect ecosystem quality. And carcinogenic effects and respiratory and other diseases will affect human health. These three damage categories are nowranked. 
Since it is impossible to accurately assess each factor (complete and consistent figures are just not available), ranking is subjective. Researcher Dr Hofstetter in Switzerland has developed a ‘triangle’ method to assess environmental effects. Sixty five respondents ranked human health as the most important value at (figure 3), with ecosystem health second and conservation ofnatural resources third. 
In terms of a pick-and-place machine’s environmental impact on resources, the most important factor was energy use, but results depend on how the factory generates its energy. Generally, renewable energy has much lowereffects than fossil fuels. As many machines are located in China, effects need to be calculated for the ‘worst case’ of coal fired power stations besides greenhouse gas emissions of CO2, NO2 and SO2 – which includes U, Th and Hg. Figure 4 shows the major environmental impacts from an Assembleon pick-and-place machine. Major effects include energy consumption; respiratory problems from organic substances; followed by climate change, carcinogens and fossil fuels. 
Telecoms board assembly
The different processes undergone by a typical mobile phone assembly with 364 components (1456 components on a four-fold board) will have the impact shown in figure5. Each factor contributes between 0 and 100 percent, with the printed wiring board being most significant at around 50 percent and solder and SMTprocessing being less influential. 
Although lead free solders are much less toxic than Sn-Pb types, the process is more energy intensive (figure 6). That is mainly because it has a higher melting point (typically: >215ºC versus >183ºC). 
Alongside savings in components and boards, avoiding rework reduces lifetime solder paste usage from 14.5 kg to 3.5 kg, and reduces energy for refl ow soldering. It also means an average three fewer 2.5kW rework stations per line than for sequential pick-and-place machines. Proposal: energy labels
The overwhelming importance of energy consumptionto the environmental effects of a pick-and-place machine has led Assembléon to propose anenergy label method based on the EuP,which covers eco-design requirementsfor designing and developing productsthat consume significant energy andnatural resources. The company isforwarding this proposal based oncomparisons of six pick-and-placemachines using the ‘Eco-Indicator99’ method with their calculationsindicating the need for such labels. The labels themselves are simple (the EuP Directive proposes labels with between six and nine classes). With the ‘average’ energy consumption of all available products being rated at ‘100’, an energy consumption of 55 percent or below ‘average’ gives a product a ‘class A’ rating (figure 7). 
It is not just the initial rated figures that are important though, machines must keep working at maximum efficiency across the equipment lifetime. Assembléon is addressing this, too, with its Assembléon Performance Solutions (APS) program maintaining output, quality and yield, uptime and efficiency over the whole working life ofthe machine. -------------------------------------------------------------------- ------------------------------------------------------- Life cycle assessment A Life Cycle Assessment (LCA) estimates the damage a product will have on the environment. It covers extraction of the raw materials, as well as the effects of manufacture, packaging, distribution, use and product disposal. The ‘Eco-Indicator 99’ method (now ISO 14042) was developed in the 1990s to estimate a product’s environment effects. It was first adopted by the Dutch ministry of environment (VROM) to assess new product designs, and works well for assessing a pick-and-place machine across its life. There are three steps to ‘Eco-Indicator 99’. First, it makes an inventory of processes in the product life cycle (LCA tree), and the flows to and from them. It then calculates the damage of these flows using ‘eco-points’. Finally, the data is normalized, multiplied by a weighting factor, and summed. One thousand eco-points give the environmental effects of one average European citizenfor a year. ------------------------------------------------------- ------------------------------------------------------- Machine design determines energy consumption 
As part of its environmental efforts as a Philips company, Assembléon some time ago upgraded its existing equipment ranges, and in 2003 included environmental performance in the specifications for its new ASeries line. As with much electrical equipment, energy consumption is a good measure of overall design quality and machine efficiency. Several other factors also affect energy performance. High throughput spreads environmental effects across more boards, and Assembléon has increased the output of its A-Series machines using a simple software upgrade three times since introduction. For the AX-501, it is now 165K components/hour – sometimes allowing only one machine to be used instead of two. The A-Series was also designed for low weight (3200 kg for the AX-501) to make transport easy. Energy-efficiency motors use energy recuperating controllers and moving masses and friction have been reduced, which also raises reliability and placement quality. The machines have low compressed air consumption, and have an energy saving mode that switches off unnecessary equipment. Preparing programs offline similarly eliminates unnecessary energy consumption. The footprint of the A-Series has been minimized, now at 3720 x 2285mm, to reduce requirements for air conditioning and lighting per square meter of facility space. Consumption of consumables like lubricants was also reduced. Modular design improves environmental performance by lengthening equipment lifetimes and delaying disposal. Here, too, planning at the equipment design stage can greatly reduce environmental effects, with above 99 percent of an AX-501 machine by weight recyclable. Perhaps most importantly, high yields mean that fewer components are placed uselessly, and fewer (expensive) populated boards are wasted. Often neglected, rework is a pure waste of all energy and resources put into it. According to Assembléon, the parallel placement technique used in its A-Series machines give single-figure defects per million placements (typically 50 dpm) giving a difference in FPY (first pass yield) of above 20 percentcompared to sequential machines. ------------------------------------------------------- About the author
Sjef van Gastel is Manager, Advanced Development at Assembléon. | 
