Swapping a gas boiler for an electric one: the real cost dilemma
We break down the real cost of replacing a gas boiler with an electric one. Savings on bills or higher electricity use? Technical data and viewpoints.
English · Original discussion in Spanish · Published
Is it worth replacing a gas boiler with an electric one? The savings on the monthly gas bill clash with the running costs and the real efficiency of electricity.
Deciding to switch a heating and hot water system from natural gas to an electric solution is a calculation that goes far beyond simply comparing monthly bills. One user raised the idea of eliminating the fixed cost of natural gas during months of low demand, hoping for substantial savings, but the collective response points to consumption optimisation and the technology used as critical variables.
The dilemma of electrical capacity and fixed costs
The main stumbling block when moving to electric systems, especially for "instant" hot water, is power demand. It requires an installation with a high contracted capacity (figures of 10-12 kW were mentioned), which on its own raises the fixed charge on the electricity bill. This contrasts with the initial perception of removing a fixed gas charge that is paid even when unused.
Some propose hybrid or alternative solutions to full replacement. The idea of using an electric water heater (with a tank) for hot water has been raised, keeping the gas boiler solely for heating, or even, in extreme cases, adapting the existing boiler to run on propane or butane, although this requires specific modifications to the unit.
Efficiency and types of heating: beyond the kW
Efficiency is a concept that sparks technical debate. While some argue that the cost per unit of heat generated by an electric resistance element is high compared with gas energy, others point out that performance depends entirely on how those calories are used. It is not enough to plug in a device; heat distribution —radiation, convection— determines whether consumption translates into real comfort or wasted energy.
The effectiveness of conventional electric radiators in urban flats has been called into question, with suggestions that their performance is limited when it comes to covering all areas of a home. In contrast, sealed systems with oil-filled reservoirs are defended, where heat management is more controlled, although this introduces new maintenance variables, such as corrosion.
The reality of maintenance and corrosion in sealed systems
Moving from an open system to a sealed one, as a water-based heating circuit implies, brings concerns about corrosion. While some argue that the absence of air in a sealed circuit minimises the risk, others note that dissolved oxygen in the water, combined with galvanic pairs between different metals in the installation, accelerates rusting. This is a technical variable that cannot be solved by simply changing fuel.
The initial installation cost, the payback period and the durability of components are factors the technical analysis does not address, yet they are crucial for any assessment of economic viability. Is the perceived saving on the gas bill enough to justify the initial investment and the complexity of a complete energy overhaul?
Related discussions on the forum
Deciding to switch a heating and hot water system from natural gas to an electric solution is a calculation that goes far beyond simply comparing monthly bills. One user raised the idea of eliminating the fixed cost of natural gas during months of low demand, hoping for substantial savings, but the collective response points to consumption optimisation and the technology used as critical variables.
The dilemma of electrical capacity and fixed costs
The main stumbling block when moving to electric systems, especially for "instant" hot water, is power demand. It requires an installation with a high contracted capacity (figures of 10-12 kW were mentioned), which on its own raises the fixed charge on the electricity bill. This contrasts with the initial perception of removing a fixed gas charge that is paid even when unused.
Some propose hybrid or alternative solutions to full replacement. The idea of using an electric water heater (with a tank) for hot water has been raised, keeping the gas boiler solely for heating, or even, in extreme cases, adapting the existing boiler to run on propane or butane, although this requires specific modifications to the unit.
Efficiency and types of heating: beyond the kW
Efficiency is a concept that sparks technical debate. While some argue that the cost per unit of heat generated by an electric resistance element is high compared with gas energy, others point out that performance depends entirely on how those calories are used. It is not enough to plug in a device; heat distribution —radiation, convection— determines whether consumption translates into real comfort or wasted energy.
The effectiveness of conventional electric radiators in urban flats has been called into question, with suggestions that their performance is limited when it comes to covering all areas of a home. In contrast, sealed systems with oil-filled reservoirs are defended, where heat management is more controlled, although this introduces new maintenance variables, such as corrosion.
The reality of maintenance and corrosion in sealed systems
Moving from an open system to a sealed one, as a water-based heating circuit implies, brings concerns about corrosion. While some argue that the absence of air in a sealed circuit minimises the risk, others note that dissolved oxygen in the water, combined with galvanic pairs between different metals in the installation, accelerates rusting. This is a technical variable that cannot be solved by simply changing fuel.
The initial installation cost, the payback period and the durability of components are factors the technical analysis does not address, yet they are crucial for any assessment of economic viability. Is the perceived saving on the gas bill enough to justify the initial investment and the complexity of a complete energy overhaul?
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Summary of a discussion on Burbuja.info - Foro de economía, actualidad y política., translated from Spanish and reviewed before publication. Read the full discussion (25 replies).
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