Almost none of the important examples in the history of the solar house survive in anything like original condition. (Fred Keck's Sloan house, and Frank Lloyd Wright's Solar Hemicycle are the major exceptions.) In part this may be due to the phenomenon of shearing layers, discussed in the previous post. And in part this may be due to the fact that they were generally not designed to be lovable.
In his book The Original Green, Stephen Mouzon argues that buildings must be lovable in order to be sustainable, because if they are not lovable they will not be preserved. This page by Mouzon has a summary, or for the full discussion, buy the book. Mouzon's idea built upon Stewart Brand's comment in How Buildings Learn that we need to understand "What makes some buildings come to be loved?”
In The Solar House, though I did not use the word lovable, I did discuss the fact that many landmark solar houses were designed as 'science projects' without much attention to architectural aesthetics. Recently on the blog I extended this line of inquiry: The Saskatchewan Conservation House: Aesthetic Questions.
Of course "lovable" was not a general aim of 20th-century architecture. And of course the term "lovable" has a conceptual problem a mile wide: it's purely subjective. (Mouzon seems to be a traditionalist.) More problematically for the Preservation disciplines, what is generally lovable changes with time. You might want to preserve an unloved building because odds are it will be loved in the future.
Still, I think the concept of lovable, however slippery, does hold some value in assessing why experimental solar houses have such a poor track record of being preserved. If more of those houses had been designed with more lovable features, would they have a better survival rate? Or maybe we need to develop some more love for historic experiments.
Related: To Love a Building, a page by a student of mine (not about solar houses)
Loosely related: Loveabilty (with an e) is also discussed here.