An installation capable of being electrically autonomous comprising elements to be powered (12, 20, 30) including: - a building comprising at least one room delimited by at least one wall and a roof, and - connection means for the connection of at least one additional electrical device, the installation including means for powering the elements comprising: - means for generating energy from a natural source, including photovoltaic panels, - means for storing energy (56; 56A, 56B), - means for interconnecting (58, 62, 64; 58A, 58B, 62A, 62B) the storage means and/or the generation means to the elements to be powered, the installation also including: - an electricity distribution terminal, located outside the building and including the connection means for the connection of said at least one additional electrical device, which is an external electrical device, - means for measuring (72; 72A, 72B) at least one parameter (I 72; I 72A, I 72B) relating to the energy stored in at least one part of the energy storage means, and - means for controlling (66, 68, 67; 66A, 66B, 68A, 68B) the interconnection means depending on the values obtained by the measuring means, so that if the energy stored in the at least one part of the storage means is less than a threshold value, the electrical power supply of at least one of the elements (20, 30) other than the building is prohibited, - a charger including a DC converter placed downstream of the energy generation means, - and in that the installation includes, at the output of the charger, two electrical branches in parallel, a first branch including a first inverter suitable for transforming into alternating current the electric energy produced by the energy generation means and downstream whereof the building and the electricity distribution terminal are connected in parallel, and a second branch which includes the energy storage means and downstream of these energy storage means a switch and a second inverter formed by a DC/AC current converter (54, 60; 54A, 54B, 60A, 60B) placed between the energy storage means (56; 56A, 56B) and on the one hand the building and on the other the electricity distribution terminal. - a building comprising at least one room delimited by at least one wall and a roof, and - connection means for the connection of at least one additional electrical device, - means for generating energy from a natural source, including photovoltaic panels, - means for storing energy (56; 56A, 56B), - means for interconnecting (58, 62, 64; 58A, 58B, 62A, 62B) the storage means and/or the generation means to the elements to be powered, - an electricity distribution terminal, located outside the building and including the connection means for the connection of said at least one additional electrical device, which is an external electrical device, - means for measuring (72; 72A, 72B) at least one parameter (I 72; I 72A, I 72B) relating to the energy stored in at least one part of the energy storage means, and - means for controlling (66, 68, 67; 66A, 66B, 68A, 68B) the interconnection means depending on the values obtained by the measuring means, so that if the energy stored in the at least one part of the storage means is less than a threshold value, the electrical power supply of at least one of the elements (20, 30) other than the building is prohibited, - a charger including a DC converter placed downstream of the energy generation means, - and in that the installation includes, at the output of the charger, two electrical branches in parallel, a first branch including a first inverter suitable for transforming into alternating current the electric energy produced by the energy generation means and downstream whereof the building and the electricity distribution terminal are connected in parallel, and a second branch which includes the energy storage means and downstream of these energy storage means a switch and a second inverter formed by a DC/AC current converter (54, 60; 54A, 54B, 60A, 60B) placed between the energy storage means (56; 56A, 56B) and on the one hand the building and on the other the electricity distribution terminal.