The Tokyo Gas Kohoku NT Building, completed in March 1996, was built with the objective of achieving overall savings of energy and natural resources throughout the entire life cycle of the building, from construction to demolition. The building is expected to reduce primary energy consumption by 35% and lifecycle co2 emissions by 25%. This was combined with the positive use of natural energy sources and the introduction of a cogeneration system with an absorption chillerheater using waste heat as input for its generators.
In a university building in Boston, IAQ complaints prompted an increase in outdoor air ventilation, causing a large increase in energy use. C02 readings were then taken in an auditorium, cafeteria, offices, and classrooms. The readings were used to calculate occupancy estimates and to simulate operation of a demand-controlled ventilation (DCV) system. The differential equations were solved in a spreadsheet program using a Runge-Kutta macro. A PID control system was also simulated. Ventilation adjustments were input to DOE-2 to estimate energy savings. A two year payback was estimated.