Energy autonomy of a house: solar panels, batteries, geothermal energy
The energy autonomy of a home has long been seen as an idealistic project isolated in remote areas. In recent years, it has become a reasonable goal for an increasing number of buyers and homeowners, driven by the continuous decrease in equipment costs, the sustained rise in energy prices, and a desire for resilience in the face of strains on the grid. This guide provides an overview of different technical solutions, their costs in 2026, and the levels of autonomy realistically achievable.
Three levels of autonomy to distinguish
The term energy autonomy encompasses very different realities depending on the degree of independence aimed at from the public grid. In practice, three levels of autonomy stand out.
Simple self-consumption involves on-site production of some of the electricity consumed, generally through photovoltaic solar panels, without storage. Excess production is fed back into the grid, and electricity not covered by solar production is drawn from the grid. The autonomy level achieved depends on the match between production and consumption: typically between 25 and 50% self-consumption without batteries, depending on usage and sunlight.
Self-consumption with storage adds a domestic battery to the setup, allowing storing electricity produced during the day for nighttime consumption. This level can achieve 60 to 85% self-consumption depending on the installation size and consumption profile. The building remains connected to the grid for winter periods and peak demand.
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