canon – How to avoid clogging / drying out of an inkjet printer if it is not used over a longer period of time?

I am planning to purchase an inkjet printer: either an a Canon imagePrograf Pro-1000 or an Epson SureColor SC-P900.

During the first few weeks I will have some printing jobs. But then the printer will not be used for 6 to 12 months.

1. During the shutdown time it will probably not possible to supply the printer with power. How do I avoid the drying out or clogging of the print head and the ink system?

2. If the printer can be powered, do they automatically clean themself from time to time?

I checked in the manuals and on the internet but I did not find any information on this.

Thanks.