"I did read the article. Interesting indeed. But they forgot to mention what to do if electrical system fails in flight."
Don't forget Pneumatic systems aren't 100% reliable either, ducting can fail, valves can fail, the computers driving the valves can fail. Seems to me that 2 gens. per engine is more then reliable then one bleed source per engine (one at any given power setting that is) also I imagine a RAT would still be available and for the most crucial systems, inverting DC batteries may be a possibility.
"Not if the plane is operating on AC
not DC. Current aircraft are all DC."
What modern commercial jet doesn't use 400 hz AC
Sounds like the plan on the e7 is to skip the CSD's and go solid state to convert the variable freq. to constant for the systems that need it. Much similar to a Dash-8's power system.
"Also - bleed air installation won't be removed as you mentioned since still some bleed air is needed. The plane won't be bleedless - it will just use much less bleed air that current planes."
The article only mentioned bleed air being used at idle power for stability through BOV's (bleed off valves) I'm sure only, meaning the bleed air will be sent straight out the side of the cowl. I'd have to take a guess that this may be used to prevent compressor stalls as well, when changing power settings, but never having worked on a bleedless engine I can't be sure this would be required.