That’s weird design and comparison; to get similar performance from a tool without electricity, you’d need some heat transfer mechanism between solar collector unit and consumer - steam? sand? just heat sufficient thermal mass and then load it with things to be cooked? I just hate the idea to waste efficiency by transferring energy through electricity here, while all heat losses could have been turned to profits instead. Electricity-centered approach of modern solarpunk pushes just a bit too far, too high tech in places where more traditional approaches could have been used.
Well, I must say that if you already have a solar electrical power system, it would be quite convenient to just hook up the oven there. Then on the other hand any conventional oven could probably do this same trick.
These are things that just came to my mind after reading this; I’m probably going to think about these more and try them next summer. This article is inspiring indeed!
https://permies.com/t/65217/DIY-Solar-Oven
https://www.sciencebuddies.org/science-fair-projects/project-ideas/Energy_p018/energy-power/build-a-simple-solar-oven
https://www.solarbrother.com/en/making-a-solar-oven/
Oh come on, just grab some sunlight and go. We’ve built these babes with damaged frenel lenses from huge tvs in junkyard.