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ECO's Overview



Energy Conservation Opportunities (ECO's)

The tables on the following webpage list the ECO’s identified by the AUDITAC project as being potential areas to assess during an Inspection or Audit of a building, with the ultimate aim of reducing the energy consumption of the Air Conditioning System(s) within the building. These ECO’s were produced by Work Package 4 of the project.

Structure of the ECO List

The main purpose of an Energy Audit is to identify a suitable set of actions that should lead to significant energy savings, within the specified operational and financial constraints.
In the Preliminary Audit phase, a set  of candidate ECOs is identified following the procedure outlined in WP3 report. The ECOs are selected from a list in which they are grouped into the following categories and subcategories:

E.1 Solar gain reduction / Daylight control improvement
E.2 Ventilation / Air movement / Air leakage improvement
E.3 Envelope insulation
E.4 Other actions aimed at load reduction

P.1 BEMS and controls / Miscellaneous
P.2 Cooling equipment /  Free cooling
P.3 Air handling / Heat recovery / Air distribution
P.4 Water handling / Water distribution
P.5 Terminal units
P.6 System replacement (in specific limited zones)

O.1 Facility management
O.2 General HVAC system
O.3 Cooling equipment
O.4 Fluid (air and water) handling and distribution

In the “Envelope and Loads” categories, ECOs aimed at reducing the building cooling load are listed. These ECOs may be either of the operational type, or may involve renovation work on the building envelope. Therefore, the evaluation methods may be similar to those normally applied either to category “O&M” or “Plant”.
“Plant” ECOs involve more or less radical intervention on the HVAC system. Their applicability should therefore be carefully assessed both from the technical and economical standpoint;  for this purpose, a review of the main cost-benefit evaluation methods is presented in this report.
The “O&M” ECOs include all actions that may in general be implemented in a building, HVAC system, or facility management scheme. The costs involved by such ECOs are generally limited if not negligible: application is therefore normally recommended, provided their technical feasibility is assessed.
Several of the ECOs of each of the above categories may be effectively implemented with the aid of a Building Energy Management System (BEMS). Such circumstance is highlighted in a specific column of the ECO list.
The CAT tool refers explicitly to these ECO’s where appropriate.


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