Energy audit
When the object of study is an occupied building then reducing energy consumption while maintaining or improving human comfort, health and safety are of primary concern.
An energy audit of a home may involve recording various characteristics of the building envelope including the walls, ceilings, floors, doors, windows, and skylights.
The leakage rate or infiltration of air through the building envelope is of concern, which can be affected by window construction and quality of door seals such as weatherstripping.
The energy billing history from the local utility company can be calibrated using heating degree day and cooling degree day data obtained from recent, local weather data in combination with the thermal energy model of the building.
A home energy audit is often used to identify cost effective ways to improve the comfort and efficiency of buildings.
Recently, the improvement of smartphone technology has enabled homeowners to perform relatively sophisticated energy audits of their own homes.
Examples include the Energy Trust of Oregon program[5] and the Seattle Home Resource Profile.
LCEC also targets the creation of a special fund used for the implementation of the energy conservation measures resulting from the study.
Numerous audit procedures have been developed for non-residential (tertiary) buildings (ASHRAE;[12] IEA-EBC Annex 11;[13] Krarti, 2000).
Audit is required to identify the most efficient and cost-effective Energy Conservation Opportunities (ECOs) or Measures (ECMs).
Energy conservation opportunities (or measures) can consist in more efficient use or of partial or global replacement of the existing installation.
The only way to ensure that a proposed audit will meet your specific needs is to spell out those requirements in a detailed scope of work.
Taking the time to prepare a formal solicitation will also assure the building owner of receiving competitive and comparable proposals.
For example, while lighting is typically a base load, the heat generated from that lighting must be subtracted from the weather sensitive cooling load derived from the slope to gain an accurate picture of the true contribution of the building envelope on cooling energy use and demand.
In most corporate settings, upgrades to a facility's energy infrastructure must compete for capital funding with non-energy-related investments.
A complete audit procedure, very similar to the ones proposed by ASHRAE and Krarti (2000), has been proposed in the frame of the AUDITAC[17] and HARMONAC[18] projects to help in the implementation of the EPB (“Energy Performance of Buildings”) directive in Europe and to fit to the current European market.
The following procedure proposes to make an intensive use of modern BES tools at each step of the audit process, from benchmarking to detailed audit and financial study: The advent of high-resolution thermography has enabled inspectors to identify potential issues within the building envelope by taking a thermal image of the various surfaces of a building.
For purposes of an energy audit, the thermographer will analyze the patterns within the surface temperatures to identify heat transfer through convection, radiation, or conduction.
For those who cannot afford a thermal inspection, it is possible to get a general feel for the heat loss with a non-contact infrared thermometer and several sheets of reflective insulation.
After this, reflective barrier insulation is taped securely to the walls in 8-foot (2.4 m) by 1.5-foot (0.46 m) strips and the temperatures are measured in the center of the insulated areas at 1-hour intervals for 12 hours (the reflective barrier is pulled away from the wall to measure the temperature in the center of the area which it has covered).
Interest in energy audits has recently increased as a result of growing understanding of human impact upon global warming and climate change.
