Here's the technical article to which you referred, complete with appendices:
http://www.sustainablecommunication...inted-web-based-and-tablet-e-paper-newspaper/
That's the second edition of an article published in 2007. From its new preface:
Here's another article by the same authors, from 2009:
http://www.sustainablecommunications.org/printed-and-tablet-epaper/
From its abstract:
The first article found that the 542 MJ of energy needed to produce the newsprint accounted for the majority of the 859 MJ per reader per annum consumed by the newspaper (Appendix 4.1). For the web-based newspaper, with 30 minutes of reading, the 862 MJ of energy per reader per annum mostly consists of the 613 MJ needed to power the computer and monitor for an average of 4 hours per day (Appendix 4.6), even though only 30 minutes are spent reading the electronic newspaper.
Those numbers assume the computer consumes 160 W and a separate CRT display consumes another 120 W. A modern MacBook Pro laptop consumes about 20 W during passive display, less than a tenth of what they assumed in their 2007 article. You can see why their more recent article came to a rather different conclusion.