comments:
I think you are looking at residential style on demand electric when you are talking about 10-12k watts. There are plenty of on demand heaters out there that 'only' require 3000-4500w that are 'point of use'. For example: KENUOS Electric Tankless Water Heater 110V 3000W,Point Of Use Instant Hot Water Heater with Digital Display & Remote Control Fast Heating Compact Under Sink Water Heater for Kitchen,Bathroom - Amazon.com https://www.amazon.com/KENUOS-Electric-Tankless-Instant-Bathroom/dp/B0GVX5PPWH/ref=mp_s_a_1_13_sspa?dib=eyJ2IjoiMSJ9.1jgibG5nOlKfx2ndIcCtChqSpiodEKqB7NqTNN5Jy7D5xeAaav8lRWW9Qw77FZ86MRLvVPbxiye2BcPV0xguLOAIQ6I-Tte1xz4LtZjC9i4Yn-Up_dAOO7CwUiUo1jdiLXmePuX2Qf8oYjWuZoynbZMGqZy-aS_JUVHQT1fdefmNkRwQX1zylispRJ3BQe8u4FqjNrcg6b5e1_HLdCX8Ag.kA87fRRpjgFqL_EkamEmE44Xvc7dw-jzcR9wzjsc8Zw&dib_tag=se&keywords=electric+on+demand+point+of+use+water+heater&nsdOptOutParam=true&qid=1780704981&sr=8-13-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9waG9uZV9zZWFyY2hfbXRm&psc=1 That said, it's still going to require big batteries and inverter for boondocking. Good luck!