4 ms·

400% compared with what? and how?

• AndrewDucker 3y ago
  They can shift 4x the amount of heat than the same amount of energy would generate.
• jdlshore 3y ago
  A resistive electric heater converts 100% of its energy to heat, by essentially wasting it. A natural gas heater converts about 95% of its energy to heat, by burning it. A heat pump converts about 3x its energy to heat, by acting as a sort of reverse air conditioner that’s cold on the outside and warm on the inside.
• thaumasiotes 3y ago
  400% is probably the ratio of thermal energy released by the heat pump to energy (of whatever kind) used to operate the pump.
  • baking 3y ago
    That has to depend on the outside temperature.
    • KMag 3y ago
      And also the indoor temperature. My recollection from designing these in class about 20 years ago is they typically operate at about half the Carnot efficiency.