Renewable energy sources for backup energy supply of small wastewater plants and individual households

Abstract

These researches concern the use of renewable sources of electricity during emergency shutdowns for uninterrupted operation of water management systems. The ability to purify drinking water during a power outage requires a backup power source. A mobile power plant, which is usually used as a backup power source during blackouts and emergencies, is known to cause environmental pollution and greenhouse gas emissions. The use of wind energy for these purposes requires the location of wind stations next to small treatment plants and households in order to quickly switch to autonomous mode, which does not always meet the territorial requirements and wind resources of the region. Open areas for the location of solar panels make the use of this type of renewable sources as a reserve in the conditions of military operations in Ukraine not quite suitable. On the basis of foreign experience in the use of small hydroelectric power plants (MHPs) and with different layouts of their location when working at sewage treatment plants, four possible options for providing electricity to sewage treatment plants and households during a blackout are proposed for the conditions of Ukraine. The option of the location of the MHP, which uses the energy of water transported through pipelines and which has successfully proven itself at operating treatment plants, is considered. Variants of using the pressure of an artesian well are proposed: MHP located in a vertical well that supplies artesian water under pressure; when an active artesian well supplies water under natural pressure at a constant flow rate to an above-ground (or underground) tank that simultaneously supplies normal household needs and a connected turbine-powered alternator. In addition, an option for the location of the MHPS was considered for the treatment and further use of rainwater sewage, including for the use of rainwater collected from "green roofs" in a tank-reservoir. The peculiarities of using this scheme are that it is easy to combine it with the case of using energy obtained from artesian wells. The proposed technological solutions allow for significant energy savings, including in places where high-quality water supply from artesian wells is possible, depending on the hydrogeological conditions of the area.