Global primary energy demand is increasing.Around 75 percent of the life cycle cost of the building is during the operation and maintenance phase and of this, a large part of the cost is actually the cost of energy.Energy Performance Index is a metric to understand the annual energy consumption of a building per unit area; the lower the EPI of the building, the more efficient is the building.For optimum heating/cooling and lighting, the orientation of the building is the first thing that needs to be decided before designing the building.
Energy consumption by the HVAC system of a building can be controlled by the following means:
Variable Frequency DriveVariable Air VolumeHeat Recovery WheelPiping and duct insulationEconomizer
Daylight penetration within in a building can be increased by skylight, light shelves and glazing on the windows.Electricity-efficient lighting system can be achieved with devices such as Dimmer, Sensor and Timer control.Depending on the climate and location of the building, the U-values and R-values of the opaque components of the building, such as the wall ans the roof, are determined.Vertical fenestration has two requirements - the assembly U factor and the SHGC requirements.Compensating for a reduced performance of one component of a building envelope with an increased performance of another component is called the trade-off method of achieving compliance with Building Codes.A net zero energy building is a building which has zero net energy consumption.
There are multiple variations within this net zero energy building, such as:Net Zero Site EnergyNet Zero Source EnergyNet Zero Energy CostsNet Zero Energy Emissions