Environmental impact e-learning much lower than campus

In looking for some papers for my ICT Sustainability students to read, I came across "Designing low carbon higher education systems: Environmental impacts of campus and distance learning systems" by Roy, Potter and Yarrow at Open University UK (2007). They, not surprisingly, found that Distance Education uses about 65% less energy (and correspondingly lower carbon emissions) than campus-based courses. But they found e-learning only produced a modest 20% energy reduction over print-based courses, as students tended to print out the e-learning materials. It would be interesting to see if this still applies in 2015, with student more used to electronic documents and having mode potable devices to read them on.