Secondary heat from hot water is an extremely useful residual product – a combination of energy savings and optimal use of natural resources. The “Bathroom System” came as a natural extension of another project – “System For Energy Savings”, which is based on the overall concept of residual energy from hot water. Ecoboil is an advanced project based on analysis, design and synthesis of ideas, based on real results achieved with another project. It is intended to be mounted as a device on the wall in the bathroom, in the adapted bathing space. The development of concepts such as “green energy” and “intelligent buildings” is a prerequisite for the entry of such products, with the widespread use in newly built houses, passive houses, residential complexes, hotels, shopping centers, business buildings and more. The development of experimental models and a prototype will be forthcoming.