Should the next standby power target be 0-watt?

Panel: 7. Appliances, products, lighting and ICT

This is a peer-reviewed paper.

Authors:
Alan Meier, Lawrence Berkeley National Laboratory, USA
Hans-Paul Siderius, Netherlands Enterprise Agency, The Netherlands

Abstract

Many countries have adopted goals to reduce standby power consumption in appliances. The initial target in the early 2000’s was 1 watt, but subsequent policies sought further reductions to as low as 0.5 watt. Considerable progress has been made in minimizing standby power use, but a new generation of Internet-linked devices now needs to maintain network connections. Thus standby energy is on the rise again. This situation has led to consideration of new, lower standby targets that will take into account network connections. We propose a standby target of 0 watt, but only for a brief period operation. During that time the device must operate for several minutes with no power draw and without losing network connectivity or other critical functionality. Subsequent revisions to the target would extend the minimum length of autonomous operation to 10 minutes or longer. To meet this specification, manufacturers will need to combine higher efficiency operation, energy storage, and harvesting ambient energy from the environment. Mobile phones, tablets, and other portable products have already incorporated these technologies although harvesting ambient energy sources is still in its infancy. This proposed 0-watt standby specification will give devices greater resiliency to power interruptions and will potentially enable saving energy consumption in higher modes. Further research is still needed to demonstrate that sufficient energy can be collected from the environment and can be economically stored. We performed case studies to assess actual requirements and aspects requiring further development. A new test procedure will also be needed in order to fairly capture the 0-watt behavior. This 0-watt specification reflects the convergence of three important trends: greater efficiency during standby operation, declining costs for storage, and new technologies for harnessing ambient energy sources—a trend that will also affect energy use in many other devices.