Energy Efficiency

on . Posted in HVAC Engineering

Energy efficiency rating, abbreviated as EER, also called energy efficiency ratio, a dimensionless number, is a measure used to quantify the energy efficiency of appliances and systems, particularly in the context of energy consumption and conservation.  It provides consumers with a standardized way to compare the energy efficiency of different products and make informed decisions when purchasing appliances.

Energy efficiency ratings are often displayed as labels or ratings on products such as household appliances, electronics, lighting, heating, cooling, and ventilation systems.  The ratings help consumers understand how efficiently a particular product uses energy, which can have implications for both environmental sustainability and cost savings.

The specifics of how EER are calculated and presented can vary depending on the region and the type of product.  In some cases, a higher rating indicates greater energy efficiency, while in others, lower ratings might be better.  Common rating scales include letters (such as A, B, C) or numerical scales.  These ratings are typically developed and regulated by government agencies or industry standards organizations to ensure consistency and accuracy.  They often take into account factors like energy consumption, performance, and other relevant metrics to provide a comprehensive evaluation of energy efficiency.


Energy Efficiency Rating formula

\( EER \;=\; ( H_o \;/\; P_i ) \; 100 \)

\( H_o \;=\; EER \; P_i \;/\; 100 \)

\( P_i \;=\; H_o \; 100 \;/\; EER \)

Symbol English Metric
\( EER \) = energy efficiency \(dimensionless\)
\( H_o \) = heat output \(Btu\) \(J\)
\( P_i \) = power input \(W\) \(kg-m^2 \;/\; s^3\)


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Tags: HVAC Efficiency