VAV for laboratory hoods - design and costs.

Laboratories with chemical fume hoods can have HVAC systems designed for variable air volume (VAV) for the optimum in safety and cost savings. Various VAV designs are discussed with their associated advantages and disadvantages. Controls for providing VAV operation of fume hoods are outlined. A computer simulation of the energy usage for constant vs. variable volume hood operation is performed. The energy and cost savings are discussed along with a construction cost comparison of constant volume with variable volume. An economic analysis for retrofitting VAV in laboratories is performed with the VAV system in this example having a simple payback of three years and a 35% rate of return on the differential investment.