Heating Seasonal Performance Factor (HSFP) Calculator

Historical Background

The Heating Seasonal Performance Factor (HSFP) is designed to measure the efficiency of heat pumps over an entire heating season. Introduced as a comprehensive metric, HSFP accounts for varying seasonal conditions and system operation to provide a more realistic indication of efficiency than the Coefficient of Performance (COP), which measures performance under a specific set of conditions.

Formula

The HSFP formula is:

\[ \text{HSFP} = \frac{\text{HO}}{\text{EU}} \]

where:

• HSFP: Heating Seasonal Performance Factor, measured in BTU per Watt-hour (BTU/Watt-hr),
• HO: Total heat output in BTU over the season,
• EU: Total electricity used in Watt-hours over the season.

Example Calculation

If a heat pump provides 150,000 BTU of heat output and consumes 20,000 Watt-hours of electricity over the season, the HSFP is calculated as:

\[ \text{HSFP} = \frac{150,000}{20,000} = 7.5 \, \text{BTU/Watt-hr} \]

Importance and Usage Scenarios

Calculating HSFP helps identify the seasonal efficiency of heat pumps, providing critical insights for homeowners and HVAC professionals into energy usage and potential cost savings. HSFP can guide consumers when comparing different heat pumps or upgrading existing systems, ensuring optimal performance and lower operational costs.

Common FAQs

What is the significance of HSFP in HVAC systems?
HSFP reflects the seasonal energy efficiency of air-source heat pumps, offering a comprehensive measurement that considers variations in climate and operation over the entire heating season.

How does HSFP differ from COP?
While COP measures efficiency at a particular moment under controlled conditions, HSFP measures performance over a longer period, giving a more accurate assessment of efficiency across varying seasonal conditions.

What is a good HSFP value for heat pumps?
A good HSFP value typically ranges between 8 and 10 BTU/Watt-hr, but higher values are desirable as they indicate better seasonal efficiency.