Are there any? Google makes a secrete of it, do you know how to find such one?

Living and romancing in Kyoto for the last 4 years and don't know of any capsule hotels in the city. You'll have to go to Osaka for that...

there is one, but its quite far out, and a little expensive for capsule hotels.
alternatively there is a sauna in the downtown area, much cheaper and in a much more convenient location.
i forgot the details of both but found out when i was living in japan by asking at the tourist information.
ring them or give them a visit in kyoto station.