Understanding emission and efficiency: what a table really measures
Emission: on-site definition and units to know (gCO₂/kWh, kgCO₂/m².year)
A table helps you compare a system's carbon emission, at the right level. In gCO₂/kWh, we're talking about the impact per kWh of energy consumed (gas, electricity, wood, etc.). In kgCO₂/m².year, the result is brought back to the floor area and the year, so to actual use of the home. Be careful, these values depend on the emission factor used and the consumption assumptions.
Efficiency: useful efficiency vs nominal efficiency, and measurement conditions
Nominal efficiency is measured under standardised conditions, often favourable and at stabilised load. Useful efficiency describes what the generator actually delivers to the heating system, once losses are accounted for (on/off cycles, defrosting, standby, distribution). A serious table always states the measurement conditions, in particular flow/return temperatures, outdoor temperature and usage profile. To go further, you can look into the overall efficiency of a heating installation and its components.
Why the emitter changes everything: comfort, control and losses
Two installations with the same generator can give different results depending on the emitter. A low-temperature emitter (underfloor heating, correctly sized radiators) improves the operation of a heat pump and a condensing boiler. The payoff: more stable comfort, finer control and fewer losses, provided there is good balancing and water at the right temperature.
Emitters: how they influence emission depending on the heating system
High-temperature radiators: impacts on emission when water temperature rises
With radiators sized for water at 70 or 80°C, the emission is certainly there, but the generator works harder. A condensing boiler condenses less if the return is too hot. A heat pump sees its COP drop as the flow temperature rises. The result: you heat quickly, but often with more kWh consumed.
Underfloor heating and low temperature: effect on generator efficiency
Underfloor heating spreads heat over a large area. The water circulates at low temperature, often around 30 to 40°C. This low temperature improves the efficiency of a condensing boiler and the performance of a heat pump, with more regular emission and fewer consumption peaks.
Fan coil units and airflow: uses, limits and possible drift
Fan coil units are useful when responsiveness or a reversible solution is needed. But the airflow can create discomfort (noise, draughts) and encourage overheating. Without filter maintenance and without good control, emission becomes unstable and consumption drifts.
Reading and using an emission efficiency table on an RGE job
Identifying the key variables: flow/return temperature, intermittency, control
An emission efficiency table links the power actually delivered to water conditions. Start by looking at the flow and return temperatures. The lower they are, the better a heat pump or a condensing boiler works. Also check intermittency (setbacks, boost cycles) and control (thermostat, thermostatic valves, outdoor sensor) since they change the average regime.
Translating the table into technical choices: sizing, balancing, heating curve
Use the table to size for the target regime, not the "catalogue" regime that's too hot. If power drops at low temperature, adjust the emitter surface area or switch to more suitable emitters. On site, balancing secures flow rates and limits overheated rooms. Then adjust the heating curve to match the actual need and avoid short cycles.
Avoiding common mistakes: oversizing, settings, incompatibilities
The classic pitfalls are "safety margin" oversizing, a heating curve set too high, or aggressive boost cycles. Also watch for incompatibilities. A high-performance heat pump quickly loses efficiency if you keep radiators designed for 70/50°C without recalculating. A check under real conditions, followed by a settings review, often gains more than replacing the equipment.
Concrete 2026 cases: improving emission without losing efficiency (and vice versa)
Heat pump + existing radiators: when to adapt the emitter or the operating temperature
Condensing boiler: making the most of the cold return thanks to the emitters
Full renovation: insulation, ventilation and settings to stabilise emission
With Argile: costing and justifying your emitter choices based on emission
Quick energy diagnosis: comparing scenarios in under 5 minutes (emission, efficiency, emitter)
On site or in the office, you test several combinations. Argile estimates the expected emission, the generator's efficiency and the impact of the emitter choice. Low-temperature radiators, underfloor heating, or keeping the existing setup. You compare, you decide, in 5 minutes.
Pre-costing and quotes: integrating MaPrimeRénov' and CEE consistently with emitter choices
A solid quote is a consistent quote. Argile links your emitter choices to the work items, then integrates grants MaPrimeRénov' and CEE without shifting the scenario. You keep a readable costing, with clear assumptions about emission and comfort.
Technical and administrative visit: documenting assumptions and securing your RGE file
Argile helps you document what makes the difference. Readings, photos, constraints, flow temperatures, condition of the emitters. You justify your emission and sizing assumptions. The result: a cleaner RGE file, with fewer administrative setbacks.
Key figures
0.95 to 0.98
Underfloor heating
0.90 to 0.93
Convector
0.93 to 0.95
Cast-iron radiator
Frequently asked questions
Rely on the regulatory emission factors used in the DPE method (updated periodically) rather than on "in-house" values. For electricity, check whether the source is "average CO₂ content" or "marginal use," as the gap can significantly change the calculated emission. Always state the source and the year of the factor in your report to avoid disputes.
Louis Airy
COO of Argile
