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Stack Draft Caclulations

December 1st, 2011

Evaluate stack draft under potential conditions

A recent request to use the Virtual Energy Audit to predict the amount of stack draft in a revised plant configuration using a common flue provided accurate calculations based on validated predictions. The VEA provided gas flow data including exit temperatures and pressures that allowed convenient calculations under a variety of firing configurations that incorporated the theoretical draft using relative temperature values and the frictional draft values derived from the velocity and frictional factors to compute the natural draft from the furnace combustion. These data will allow for specification of fans as required to overcome any natural draft deficiencies

Turbine-Generator Analysis

January 4th, 2010

The Virtual Energy Audit becomes a valuable tool to evaluate the potential additions of turbine-generators to an existing power plant. Adding turbine-generators will have two salient results: 1.) It will provide electrical power for use in the plant and/or sales to the power grid for which either would have direct economic benefits, and 2.) If the turbine is a back-pressure version, it will provide additional lower pressure steam to use for sale and use. The VEA will provide answers on the total plant operations such as the effects of additional steam demand and generation, with its costs, and the amount of additional back-pressure steam to be balanced against steam demand. Boosting steam generation to feed the turbine-generators will have many potential effects that the VEA will easily identify.

Potential Savings

December 24th, 2009

How much savings can be accrued using the VEA? Let’s start with 3% as an initial estimate. Based on an annual fuel budget of $10,000,000.00, the savings would be $30,000.00. At $10/lb generating 10,000,000 pounds per year, the savings would be 300,000 pounds per year for a savings of $3,000,000 per year! The savings would come from implementing the efficiency measures identified by the VEA such as more efficient boiler combinations, reductions in excess air use, better fuel combinations, improvements in peripheral equipment operation, identifications of incidental losses, and on. Of course, if a plant is already operating well, the savings might only be 1%, but then for other plants the savings might be 7 to 10%. It is up to the program user to identify and then use the measures highlighted. VA:W welcomes the opportunity to consult for optimal VEA use.