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Energy Efficiency Formula:
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Energy efficiency measures how effectively energy is converted from one form to another. It's calculated as the ratio of useful energy output to total energy input, expressed as a percentage. Higher percentages indicate more efficient systems with less energy waste.
The calculator uses the energy efficiency formula:
Where:
Explanation: This formula calculates what percentage of input energy is converted to useful output energy, with the remainder typically lost as waste heat or other forms.
Details: Calculating energy efficiency is crucial for evaluating system performance, identifying energy waste, reducing operating costs, and meeting environmental regulations. It's particularly important in the UK where energy efficiency standards are strictly regulated.
Tips: Enter both energy values in kilowatt-hours (kWh). Output energy cannot exceed input energy. Values must be positive numbers.
Q1: What is considered good energy efficiency?
A: Efficiency above 80% is generally good, though this varies by application. Modern appliances often achieve 90%+ efficiency.
Q2: Why can't efficiency exceed 100%?
A: Due to the laws of thermodynamics, no system can output more energy than it consumes. Efficiency over 100% would violate conservation of energy principles.
Q3: How does UK legislation affect energy efficiency?
A: The UK has strict energy efficiency standards for buildings and appliances through programs like the Energy Performance Certificate (EPC) and Minimum Energy Efficiency Standards (MEES).
Q4: What are common ways to improve energy efficiency?
A: Insulation upgrades, high-efficiency appliances, LED lighting, smart thermostats, and regular maintenance of systems.
Q5: How does this relate to carbon footprint?
A: Higher energy efficiency typically means lower energy consumption, which reduces greenhouse gas emissions and carbon footprint.