Electricity doesn't have a thing to do with this. Maybe you're imagining those fancy Japanese toilets that sing to you.

A bidet is just a spigot with a valve. Open valve, blast ass, get clean, close. Unless you have bizarrely cold water, this is all you could ever want or need.

I use a bidet that relies on water pressure from the apartment’s plumbing. No electricity needed.

It does get cold during the winter, but it’s not bad at all and it’s so much better than using toilet paper for wiping. I still use some toilet paper for drying, but far less than I used in the pre-bidet era of my life.

Get a toilet seat bidet. It's mechanical. Doesn't need electricity, only water... which is already present!

10 years ago I bought an unpowered toilet seat bidet just to try out the concept. Still haven't gotten around to upgrading to a powered version, because it turns out that cool water is nice. I even have a plugin next to the toilet that I had installed when the house was built, because I anticipated getting a Washlet.

I still intend to get a fancy one with warm water, heated seat, and a glowing bowl (for aiming in the middle of the night ;-)). Some day.

You can have a handshower mounted next to the toilet seat. Also: what bidets require electricity? (Except the Japanese toilet and bidet in one thing.)