Among the various cases of application of off-grid electrical production systems in which FGS Energie Alternative is specialized, there are particular situations when it's extremely convenient or even obligatory for reasons of distance to keep the equipment isolated from the network.
In the aqueducts in mountain areas generally the sources or the first water treatment plants are located on the territory where the availability of water allows, with the consequence that these structures are found in narrow gorges or ravines, small valleys, very frequently unreachable even to wheeled vehicles, where a maintenance worker can only arrive on foot.
In these cases the electric current of the network is obviously absent for various reasons, first of all the fact that generally, and at least in the past, no particular electrical equipment was needed at the source.
In recent years, however, for various regulations and control needs, even on these sites it's necessary to do a series of operations that require electricity, such as water treatment, or simply
transmission of monitoring data such as levels, chemical data, etc.
The simplest solution often used is to apply a small photovoltaic system with an accumulation system, which however often proves to be unreliable, above all because in these sites we have problems of vegetation and very narrow horizon, if we are inside valleys. As a consequence, the accumulation batteries suffer, due to the irregular charge, involving frequent maintenance and instability of the system.
In these cases, FGS Energie Alternative proposes a range of micro-turbines suitable for the production of electricity, directly or with accumulation systems, necessary for these users.
Let's see for example an application of a micro turbine in line with the aqueduct.
This system is mainly used with forced ducts that have an internal pressure from 2 to 10 Bar, it's therefore effective in applications such as filtering and water purification in the aqueducts, providing, thanks to a correct sizing of the turbine and of the storage system, the necessary energy for powering 24h / 24 the service systems.
The generation system is placed upstream of the machines that are powered and, thanks to the pressurized operation of the turbine, it's possible to maintain a pressure higher than the atmospheric pressure in the turbine's diffuser (unlike the Pelton turbines) in order to guarantee the operation of the most common machines intended for filtering or any other hydraulic application.
The operation is completely automatic and does not require any intervention during his work, the bypass valve for example is regulated by a system coordinated by PLC which, when the pressure in the duct is changed, gradually opens or closes the bypass valve ensuring constant energy production. preventing the turbine from working outside the maximum efficiency range.
The system is also equipped with an additional manual bypass valve and two valves at the inlet and outlet of the micro-turbine which allow the latter to be removed for routine cleaning and maintenance operations.
In the image below we can see the detail of the impeller inside the volute:
The machine in question is able to produce about 400W of electrical power kept constant by the bypass system.
In a recent installation, for example, a storage plant with a capacity of about 7kWh coupled to a 1.2 kW inverter has been designed to meet the customer's requirements. The system proved to be effective in meeting the energy requirements of different machines up to 1 kW of power and the nominal energy consumption.
Compared to a system with only photovoltaic, we have a greater reliability of the possible accumulation battery pack, as they are constantly loaded, rather than suffer deterioration cycles of subsequent charges and discharges.
Moreover, in special cases where the power required is always comparable or lower than the one produced, it is also possible to completely eliminate the battery pack.
The possible uses that the system is able to manage range from UV lamps for water disinfection, water neutralization with CO2, Oxidation with O3, activated sludge processes, as well as all PLC control or remote control equipment.
Here are the photos of the complete system, in this case a water filtration system with CO2.
