Note that the months in this chart are for the period ending that month. So the January numbers are for mid-December to mid-January. Our energy usage clearly spiked as the temperature dropped, but on the whole it's not a huge increase. During this time last year at the old house, we used 31 kWh per day plus $154.56 in natural gas for the furnace (which was unusually high). During a one-year period we spent $1,620.76 on energy (electricity + gas) at the old house. We are on track to save about $950 per year in our Passive House. And all of this while being more comfortable than we ever were in the old house. No more cold drafts, no more chilly corners, no more icy floors.
Every home is different, so don't expect these numbers to reflect every Passive House project. But we are thrilled with the results we have seen.