A good Energy Efficiency Ratio (EER) depends on the application, but generally, an EER of 12.2 or higher for room air conditioners is considered highly efficient, and an EER of 18 is extremely energy efficient.
Understanding EER
EER, or Energy Efficiency Ratio, is a measure of how efficiently an air conditioner cools a space. It is calculated by dividing the cooling output in British Thermal Units (BTUs) by the electrical power input in watts. In simpler terms:
- EER = Cooling Output (BTUs) / Power Input (Watts)
A higher EER indicates a more efficient air conditioner. This means it can provide more cooling with less energy consumption.
What Constitutes a "Good" EER?
The definition of a "good" EER varies depending on the type of air conditioner and your priorities:
- Room Air Conditioners: Most room air conditioners are considered highly efficient if they have an EER of 12.2 or higher. An EER of 18 would be considered extremely efficient.
- Central Air Conditioners: While EER is used, central AC units are more commonly rated with a SEER (Seasonal Energy Efficiency Ratio) rating. SEER takes into account seasonal variations. For central AC, a good SEER rating starts around 15, with high-efficiency models reaching 20 or more.
- Considerations:
- Energy Savings: A higher EER translates to lower energy bills.
- Cost: More efficient units often have a higher upfront cost.
- Environmental Impact: Lower energy consumption reduces your carbon footprint.
Examples:
- An air conditioner with an EER of 10 uses more electricity to provide the same amount of cooling compared to an air conditioner with an EER of 12.
- If an air conditioner has an EER of 18, it provides 18 BTUs of cooling for every 1 watt of electricity it consumes.
Conclusion
When choosing an air conditioner, consider your specific needs, budget, and the long-term benefits of a higher EER. While a higher EER usually means a higher initial investment, the long-term energy savings can often offset the initial cost. Look for an EER rating of 12.2 or greater for room air conditioners to ensure good efficiency.
