Heat Pump Efficiency Ratings: SEER HSPF COP Explained
Clear, practical guide to SEER, HSPF and COP for heat pumps — what the numbers mean, how they affect costs, and how to choose the right unit for an eco DIY home.
Heat Pump Efficiency Ratings: SEER HSPF COP Explained Heat pump SEER HSPF numbers are the quick shorthand homeowners and DIY builders use to compare efficiency. Understanding those ratings helps predict running costs, size solar or battery systems, and choose a heat pump that suits a tight, well-insulated eco home. This guide explains what SEER, HSPF and COP actually mean, how they’re measured, how temperature and installation affect real performance, and how to use the numbers when selecting equipment for an off-grid or passive-ish build. TL;DR: - Higher SEER/HSPF and a larger COP mean lower energy use — expect 15–40% lower bills upgrading from standard to high-efficiency models. - Use HSPF/COP for heating-focused decisions and SEER for cooling; COP tells instantaneous efficiency while SEER/HSPF are seasonal averages. - Match ratings to climate and envelope tightness, and plan for 10–30% real-world performance loss from poor installation when sizing solar or batteries. What SEER, HSPF...