There are practical applications of these ideas which are already beginning to come into the marketplace and the built environment.  Looking at the New Alchemy Institute's work, A Safe and Sustainable World by Nancy Jack Todd, will give you some of the history and background of how ecological principles and systems drove research in the 1970s and 1980s.  The New Alchies provided examples that we can emulate today and should have much sooner.

Bill McDonough's ecological design principles are also useful:
waste equals food
use only available solar income
respect diversity
love all the children

Fact is, we have always been a solar economy and will always be a solar economy.  We just don't count the solar contribution.  Last I looked, the official energy budget for the USA says 3% of the energy we use goes to agriculture, the food we eat.  That includes the chemicals, fertilizers, processing, and transportation but does not include the sunlight that powers photosynthesis that actually grows the food.  Ballpark figure I come up with is about 100 times the petroleum contribution will maybe equal the solar contribution.  That means merely the agricultural sector's solar input is three times the whole energy budget of the country.

We fool ourselves all the time because we confuse economics with reality and money with life.