This is the first in a series of videos on passive solar home construction, we begin with passive solar design basics, orienting the future house on the site to take full advantage of the free heat available from the sun while keeping it cool with natural shading in the summer.
The owner of the Kenogami house sold it before he worked out any thermal battery heat-storage techniques so I don't have much to offer on that front unfortunately, and we've never been in contact with the new owner.
You may have seen this already, but here is a page on phase change building materials, I still think there is tremendous potential for material phase changes to be used for energy efficiency, there are just no mainstream products readily available on the market to date.
Our new demo house has a heat storage solution you may find interesting, it has a radiant floor heated with air tubes rather than hydronic, and those tubes will be fed with air warmed by a solar air-heating panel, so we are using the floor as a thermal battery to store solar heat. Here is an air heated slab on grade radiant floor DIY install video.