Comparing embodied greenhouse gas emissions of modern computing and electronics products.

Information and communications technology (ICT) contributes substantially to global greenhouse gas (GHG) pollutant emissions, but it is time-consuming to estimate the environmental impacts caused by the production of ICT devices, and the literature lacks coverage for newer products. Using a process-sum life cycle assessment (LCA) approach, we estimate and compare the embodied GHG emissions of 11 ICT products, including large- and small-form-factor desktop and laptop personal computers, a thin client device, an LCD monitor, newer mobile devices (an Apple iPad, an iPod Touch, and an Amazon Kindle), a rack server, and a network switch. Full bills of materials are provided via hand disassembly and weighing and are mapped to processes in the ecoinvent v2.2 database to produce impact estimates. Results are analyzed to develop simplified impact estimation models using linear regressions based on product characteristics. A simple and robust linear relationship between mass and embodied emissions is identified; a more sophisticated linear model using display mass, battery mass, and circuit board mass as inputs is slightly more accurate. Embodied GHG emissions for newer products are 50-60% lower than corresponding older products with similar functionality, largely due to decreased material usage, especially reductions in integrated circuit content.