The growing demand for datacenter services across a range of applications has resulted in significant and sustained growth in electrical energy consumption in the Information Communications Technology (ICT) sector. Currently, datacenters consume more than 2.5 % of US electricity and this percentage is projected to double in about 8 years. Efficiency improvements due to more efficient cooling, power delivery, and electronic processor chips via Moore’s law improve overall efficiency, but do not significantly slow the current growth trend; to do so requires a transformative improvement. The overall objective of the ENLITENED (ENergy-efficient Light-wave Integrated Technology Enabling Networks that Enhance Datacenters) program, therefore, is to provide a transformative change - to achieve an overall doubling in datacenter energy efficiency in 10 years through deployment of novel network topologies enabled by integrated photonics technologies. ARPA-E estimates that if the technical challenges posed by ENLITENED can be overcome, these alone would reduce projected US energy use by about 1% after 10 years and realize at least twice the number of datacenter transactions with the same amount of energy.
Industry projections show that in order to achieve future datacenter performance requirements, metal interconnects must be increasingly replaced by photonic technologies, yet costs for deployment are often prohibitive and energy efficiency is not necessarily the highest priority in the commercial sector. Though a broad industrial consensus pushes toward further photonic integration in switches and other datacenter components, in some cases, large companies will build another 80 MW datacenter to meet demand, rather than increase efficiency with photonics, due to a combination of reliability risks, cost and limited component supply.
To overcome metal interconnect limitations on future datacenter energy-efficiency performance, ENLITENED will target the critical packaging and integration challenges needed to exploit the inherent performance advantages of dense photonic interconnects and switching technology at the chip-scale within datacenters. Specifically, ENLITENED will target packaging and integration of novel and efficient photonics-enabled hardware systems that can demonstrate at least a 2-fold increase in energy efficiency at the datacenter level. To validate hardware solutions, ENLITENED will also entail modeling and simulation of the new datacenter architectures and data traffic protocols under realistic workloads, to provide quantifiable measures to validate transformative design strategies for future datacenters and retrofits.