Abstract: A microprocessor-based perimeter thermal energy control system regulates heating and cooling in the perimeter area of a building in accordance with instantaneous and integrated heat flow measurements and instantaneous temperature deviation measurements. Control of heat pumps and air conditioning units is provided as is automatic switching between heating and cooling. The inherent thermal parameters of the space are inductively determined and used by the system to continually self-adapt to the heat flow properties of the space. The gain of the heat flow based control system is varied automatically as a function of the deviation between the actual space temperature and the desired set point temperature. Morning recovery is initiated and regulated in response to instantaneous and integrated heat flow measurements and inductively determined thermal space parameters and produces a near linear stepwise change in the temperature of the space from night setback to occupancy temperature.