In 1988, two physics professors began discussing the scientific components that might lead to better energy efficiency in building construction. Bo Adamson from Lund University in Sweden and Wolfgang Feist from the Institut für Wohnen und Umwelt in Germany had read the research, dating back to the 1970s, that suggested it was possible to construct a low-energy building that was designed to exploit passive solar technologies and establish a comfortable indoor temperature with a low-energy requirement for heating or cooling.