How does a heat pump work and how is it different from a furnace?

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1. 1

   Heat pump (Wikipedia)

   WikipediaPublished Oct 16, 2026Checked Oct 17, 2026

   “A heat pump is a device that uses mechanical or thermal energy to transfer heat from one space to another. The mechanical heat pump uses electric power to transfer heat by compression. Specifically, it transfers thermal energy by means of a heat pump and refrigeration cycle, cooling one space and warming the other. In winter, a heat pump can move heat from the cool outdoors to warm a house; in summer, it may also be designed to move heat from the house to the warmer outdoors, functioning in the same manner as an air conditioner. As it transfers rather than generates heat, it is more energy-efficient than heating by gas boiler. In a typical vapor-compression heat pump, a gaseous refrigerant is compressed so its pressure and temperature rise. When the pump operates as a heater in cold weather, the warmed gas flows to a heat exchanger in the indoor space, where some of its thermal energy is transferred to that space, causing the gas to condense into a liquid. The liquified refrigerant flows to a heat exchanger in the outdoor space, where the pressure falls, the liquid evaporates, and the temperature of the gas falls.”

2. 2

   Sustainable performance enhancement of a heat recovery ground source heat pump system using field data and machine learning.

   Scientific reports (Cui et al.)Published Mar 31, 2026Checked Oct 17, 2026

   “The system parallels a conventional condenser and heat recovery condenser within a single heat pump, recovering excess condenser heat to provide 50 °C hot water during summer operation. Results demonstrate that the HRGSHP effectively limits soil temperature rise to ∼0.45 ℃ while meeting the air conditioning demand. To further enhance efficiency, a multi-objective optimization framework combining a genetic algorithm and backpropagation neural network (GA-BPNN) model with a technique for order preference by similarity to ideal solution (TOPSIS) is developed. This enables accurate energy performance prediction and optimal operational parameter setpoint determination. The optimized system achieved improvements, with average coefficients of performance for system (COPs) and heat pump (COPu) increased by 27% and 11% in winter, respectively, the energy efficiency ratios for system (EERs) and heat pump (EERu) increased by 21% and 11% in summer, respectively, and operational costs were reduced by 19%. This work provides experimental evidence and optimization guidelines for implementing HRGSHP systems in building applications.”

3. 3

   Four-step conversion of a declared seasonal coefficient of performance into hourly, capacity-aware coefficient-of-performance profiles for certified air-to-water heat pumps.

   MethodsX (Võsa et al.)Published Aug 28, 2026Checked Oct 17, 2026

   “Third, an anchoring factor rescales this shape so that the modelled system reproduces the declared SCOP over the EN 14825 rating bins - an internal-consistency guarantee of the conversion, with the shape validity assessed separately. Fourth, capacities declared on the certificate split the load between heat-pump operation and electric backup. The method is independent of any particular simulation tool and serves as a pre-processor for dynamic building simulation, building-stock analysis, or energy-performance assessment. Fitted coefficients, a two-stage worked example with expected outputs, automated tests, and a standalone Python implementation are provided in a versioned Zenodo deposit.•Converts a single declared SCOP into an hourly, capacity-aware COP profile for building simulation.•Anchoring reproduces the declared SCOP as an internal-consistency guarantee; the COP shape is validated out-of-sample on held-out manufacturers.•Requires only standard EN 14825 certificate quantities; a standalone Python implementation, fitted coefficients and automated tests are provided.”

4. 4

   Thermoelectric heat pump (Wikipedia)

   WikipediaPublished Oct 15, 2026Checked Oct 17, 2026

   “Thermoelectric heat pumps use the thermoelectric effect, specifically the Peltier effect, to heat or cool materials by applying an electrical current across them. A Peltier cooler, heater, or thermoelectric heat pump is a solid-state active heat pump which transfers heat from one side of the device to the other, with consumption of electrical energy, depending on the direction of the current. Such an instrument is also called a Peltier device, Peltier heat pump, solid state refrigerator, or thermoelectric cooler (TEC) and occasionally a thermoelectric battery. It can be used either for heating or for cooling, although in practice the main application is cooling since heating can be achieved with simpler devices (with Joule heating). Thermoelectric temperature control heats or cools materials by applying an electrical current across them. A typical Peltier cell absorbs heat on one side and produces heat on the other. Because of this, Peltier cells can be used for temperature control. However, the use of this effect for air conditioning on a large scale (for homes or commercial buildings) is rare due to its low efficiency and high cost relative to other options.”

5. 5

   Geothermal heat pumps and thermal energy networks: Technical feasibility and market adoption.

   iScience (Simpson et al.)Published Sep 9, 2026Checked Oct 17, 2026

   “Geothermal technologies, including geothermal heat pumps (GHPs) and thermal energy networks (TENs), are gaining traction as methods to efficiently meet heating and cooling loads. Changes to costs and incentives may impact adoption and can help support decision-making in effectively deploying GHPs and TENs. In this work, the updated distributed geothermal market demand (dGeo) model is used to analyze scenarios across the US demonstrating a range of economic potential and adoption for GHPs and TENs. We find that the more established GHP technology has widespread economic potential and adoption, while the newer TEN technology has economic potential and adoption concentrated in areas with dense populations. GHP adoption was projected to 251 GW-th by 2050 with high incentives and tax credits, while TEN adoption was projected at 31 GW-th by 2050. Uncertainties in cost structure translate to large variations in adoption, pointing to the importance of demonstration projects and cost-tracking efforts.”