Nordic countries are well known for their long-term efforts to preserve nature and the environment, so it is no surprise that as long ago as the late 1970s, when Ericsson considered the next generation of mobile networks’ equipment, the optimization of power efficiency was already a top priority.
The human dimension
DfE is often associated with products, although it is important to remember that there is a human element behind products, and that a clean design can only be successful if those behind such designs have a full understanding of the global benefit of such a way of working.
Prior to any DfE initiative, and even before mapping a specific project, work is done to build a common understanding of what it means, and to educate people regarding the complete chain that stems from an individual way of behaving – such as turning lights off when leaving a room, recycling papers and convertible wastes, considering phone conferences as much as possible rather that traveling, and global interactions between individuals and others in the community. Effectively, individuals are asked to consider: how in my way of working will I contribute to making things better?
There is no such thing as a successful DfE project without strong commitment from the people involved, and forgetting that fact before considering any further step forward would result in failure. The human dimension is the prime foundation for developing proper ways of working – technology will always follow.
Thirty years of improving efficiency
In 1977, the telecom industry faced a growing demand for line access and realized the tremendous increase of power that needed to be generated by the multiplication of its systems. At that time, Ericsson initiated research projects focusing on the development of new technologies for use in power supplies aimed at improving energy efficiency and subsequently reducing power consumption year after year while increasing systems performance – tough projects.
At that time, most of the power supplies were linear, and as a result of intensive research, in 1983, Ericsson launched the most advanced switching DC/DC converter (PKA), which raised power efficiency from 63 percent to 80 percent.
There is no doubt that this milestone was technically very important and it had a significant impact on the overall power community. As mentioned earlier, this was the result of research that ended in new technology at a time when environmental concerns were not a priority for many companies.
Stepping up from 63 percent to 80 percent power efficiency was a major achievement, and, indeed, Ericsson’s plan to improve on this each year has been achieved – today the figure is more than 93 percent (Figure 1), resulting in a significant reduction of carbon dioxide released by radio base station during their operation (Figure 2).
New technologies such as digital power will continue to improve power efficiency and to make systems more efficient via energy management, although there is another dimension contributing to creating better harmony with the environmental.
1980 – Ericsson DfE is already a way of working
Twenty years ago, the design and manufacture of a DC/DC converter was a complex process. For this reason, the launch of Ericsson’s PKA (Figure 3) came as a shock because of the number of innovations it introduced. These included a new building practice based on a ceramic substrate, a light design with no flying components, no unnecessary chemicals and compounds used in its manufacturing, shipping packaging based on folded cardboard, and many others.
Behind those innovations there were a number of environmental concerns and education paths regarding how to harmonize products with the environment.
Moving away from molding
The removal of molding compound from the DC/DC converter not only reduced moisture penetration, which was a serious cause of failure in those days, but the avoidance of such chemical substances when it was not a mandatory requirement for operation or safety limited the exposure of employees and users to chemicals released both during manufacturing and life-time operation.
Hybrid technology and reliability
Moving from flying components and wires to a single-side ceramic substrate and thick-film technology was another decision made to simplify manufacturing. This change optimized for higher yield, reduced fall-out and guaranteed higher reliability and longer life-time (22 years later, these equipments are still operating without any sign of failure).
Higher reliability means reduced failure rates but also reduced maintenance, which besides its direct costs, also generates traveling, re-work and associated environmental impact, especially when systems are located in remote places as extreme as the top of a mountain or in the middle of sparsely populated areas. Having this in mind at the start of the design process is vital to the way products are developed and components selected.
Cardboard packaging
One big concern when packaging such products is the amount of waste generated by the packaging required to secure the product’s quality and to guarantee that the ceramic substrate does not get damaged during transportation.
To continue using the conventional methods that were in practice in the early 1980s would have resulted in consuming huge amount of plastics and other chemicals, which was not in line with Ericsson’s objective to reduce unnecessary, non-recyclable waste.
Fortunately Nordic countries have great experience and expertise in the paper industry, so it was a natural choice for Ericsson Power Modules to consider such packaging when developing a new DC/DC power supply.
The results were very impressive, despite the market’s low expectations.. The optimization of bent-formed cardboard resulted in a very robust packaging that avoided transportation damage and the use of environmental resources.
Twenty-two years later – permanent learning
Because in the early 1980s Ericsson Power Modules had already initiated its environmental awareness strategy, and strived to achieve it, it is no surprise that over the last several years many products introduced on the market include advanced innovations that preserve environmental resources.
Improving efficiency is often a strong driving factor behind technical innovation to reduce energy consumption, but DfE covers more than that, and merely focusing on a product’s performance without considering how it impacts on the environment during all processes is not a long-term way of working.
DfE also means constantly considering whether there is room for improvement. For example, the legislation to remove lead from the electronics industry implemented about 15 years ago came at a time when Ericsson Power Modules had already released its first lead-free module, the Macrodens PKF.
If, in those days, the lead content of electronic equipment used in the telecom industry was not a major concern, it was already a sign that heavy metals released into the environment by different industries would affect it longer-term, and the tragedies happening all around the world caused concern and brought attention to the situation.
Here again, the human dimension is the most important factor driving DfE. In response to Japanese concerns, in the early 1990s Ericsson Power Modules adopted tin-silver solder in the manufacturing of most of its products, pursuing the development of lead-free converters when European RoHS legislation was still only under discussion.
In early 2001, Ericsson Power Modules released the first fully compliant lead-free DC/DC converter designed to sustain the higher reflow temperature dictated by end customers migrating to lead-free at board level. Since then it has continuously worked hard to reduce any environmental impact associated with its products.
Considering the whole chain
DfE is a permanent development process. Many manufacturing changes that Ericsson introduced almost 25 years ago are still relevant (such as cardboard packaging and encapsulation-free products), but improving and optimizing the whole chain to further reduce environmental impact is an ongoing concern.
Taking the whole chain into consideration means that when a new project starts, we need to consider how the final product will be handled when leaving our facility, and right through its life-cycle. One example to illustrate this is the new board-to-board technology introduced by Ericsson earlier this year.
The board-to-board technique results from a complete analysis of reducing other side effects impacting on the environment, such as unnecessary mass that adds fuel costs during transportation, reducing energy consumed during assembling processes both when Ericsson manufactures the product and when it is assembled by the final customer, and optimizing the product for end-of-life recycling.
Board-to-board technology is the result of years of technical expertise, but nothing would have been possible without strong commitment from everyone engaged in the project. (See Figure 4, Ericsson Power Modules’ PKD-E DC/DC module uses board-to-board technology.)
Conclusion
Design for Environment is not a concept, it is a philosophy. As the old saying goes: "We haven't inherited the earth from our ancestors, we have borrowed it from our children."
