A pass through water heater would be a good example (running 7 hours daily). Not many apartments would have a capacity to add a new water heater of such type, e

A pass through water heater would be a good example (running 7 hours daily). Not many apartments would have a capacity to add a new water heater of such type, even for human use (10-30 minutes per day, spaced out across the building in time, not all simultaneously at the same hours).