⚡ Cu ρ (75°C): 0.0214 Ω·mm²/m 🔌 NEC / IEC Standards: NFPA 70 & IEC 60364 🇺🇸 US Grid Avg: $0.175/kWh 🇩🇪 DE Grid Avg: €0.345/kWh 🇸🇪 SE Elpris: 1.54 SEK/kWh 🇳🇴 NO Strøm: 1.17 NOK/kWh 🔩 Copper Ref: $9,650/t (2026-10-24)
❄️ Heat Pump & HVAC Thermal Load · EN 12831 & ACCA Manual J Reference

Heat Pump Sizing for 300 m² (3,229 sq ft) — US Sunbelt & Mediterranean (TX/FL/CA/ES/IT)

Thermal heat loss calculation, recommended heat pump capacity (kW, BTU/h & HVAC Tons), SCOP efficiency, and annual electricity consumption.

Recommended Heat Pump14.6 kW49,817 BTU/h (4.15 Tons)
Annual Electricity Usage4,786 kWh/yrDelivers 21,060 kWh Heat (SCOP 4.4)
Savings vs Direct Electric16,274 kWh/yrSpecific Load: 46.8 W/m²
Electrical Circuit (230V)25 A BreakerPeak Compressor Input: 4.06 kW

Thermal & Electrical Specification Table (300 m² / 3,229 sq ft)

Heated Floor Area300 m² (3,229 sq ft)
Climate Zone & Design Outdoor TempUS Sunbelt & Mediterranean (TX/FL/CA/ES/IT)
Building Insulation EnvelopeStandard Double-Glazed Insulation (55 W/m² Base) (46.8 W/m² Peak)
Peak Space Heating Load14.04 kW Thermal
Recommended Heat Pump Output (Incl. DHW)14.6 kW (49,817 BTU/h · 4.15 Tons)
Seasonal Coefficient of Performance (SCOP)4.4 (340%–450% Seasonal Efficiency)
Annual Heat Demand vs Electricity Consumed21,060 kWh Heat → 4,786 kWh Electricity

Frequently Asked Questions

What kW size heat pump do I need for a 300 m² (3229 sq ft) house?

For a 300 m² (3229 sq ft) building with Standard Double-Glazed Insulation (55 W/m² Base) in US Sunbelt & Mediterranean (TX/FL/CA/ES/IT), the peak space heating load is 14.04 kW (46.8 W/m²). Including domestic hot water allowance, a 14.6 kW (49,817 BTU/h / 4.15 Ton) heat pump is recommended.

How many kWh of electricity does a 14.6 kW heat pump use per year?

With a Seasonal Coefficient of Performance (SCOP) of 4.4 over 1500 full-load equivalent heating hours, the heat pump consumes approximately 4,786 kWh of electricity per year to deliver 21,060 kWh of heat — saving 16,274 kWh/year compared to direct electric radiators.