Hobot 2s for 379 CHF was a special offer, I bought the Hobot 2s. It is mains operated with a long cable. If the power fails, an emergency power is switched on via batteries. If the windows are very dirty, a 2x cleaning cycle is necessary.
Yes, you can use this window-cleaning robot for sloping greenhouse windows. It works on inclined surfaces from 15° to 90°, including roof windows or irregular panes, thanks to its adjustable vacuum grip and sensors.