Load and energy studies determine the economic feasibility for upgrade of existing mechanical and electrical systems to increase efficiencies and improve performance of the building envelope to reduce energy losses. Loads are calculated using an 8760 hour computer program, and yearly energy use is simulated for the selected equipment types, building location, utility rates and hours of occupancy. The output is compared to capital costs, and either a simple payback or a discounted cash flow analysis helps the Owner make an informed investment decision.