The heating requirements of our passive houses:
This depends on a couple of things. The design of course, the orientation of windows, the number of floors but most importantly the overall size of the house and the number of occupants living there.
Because passive houses are so efficient, people themselves contribute significantly to heating the building though body heat, (roughly 100W per person) as well as their activities such as cooking, showering, running appliances, lighting and so on. The size and number of windows also play a big role in both losing heat and letting energy in through solar gains. This means that the heating bill for one of our houses is not fixed and varies depending on conditions.
When a family lives in one of our smaller Atlanticas they sometimes never turn on the heating at all, all year around. Conversely if a couple or single person lives in one of our larger houses, they will need to have some source of heating for the winter months.