Method of calculation of water-diverting structures of low-head hydroelectric power plant for power supply of small power consumers

In recent years and in many countries the economic development of distant regions is increasingly dependent on energy resources. This fact makes the world scientific community pay more attention to the renewable energy sources. Special attention is paid to the solar, wind and small hydropower for electrical consumers who have no possibility to connect to the central power supply lines. In the countries that have water resources the financial support is given to the development of small and micro hydropower stations. The present work presents the results of the research on the improved method of calculation of water-diverting structures of low-head hydroelectric power plant with an installed cross-jet hydro turbine that is actual for the power supply of small power consumers. The presented method can be used for the preliminary analysis of morphometric characteristics of water course as well as the basic parameters of a cross-jet hydro turbine.

Design and construction of hardware and software for autonomous observations of Transient Luminous Events

Transient luminous events (TLE) are phenomena which are currently on the rise in terms of sightings. However, there is no widespread uniform method of their observation and subsequent image processing. Therefore, our project focuses on the design and construction of hardware that can record TLE. It consists of a low gain, colour, CMOS camera with a bright, wide lens connected to a small, power-efficient single board computer. The project also includes writing software to control the hardware. The software decides whether to capture or not and at what orientation there is the biggest chance to capture a TLE. The software can process and classify the created photos based on deep neural networks. As a final product, we have developed the whole apparatus from a hardware and software point of view and installed it at the Astronomical Observatory at Kolonica Saddle in Slovakia, Central Europe. The plan for the future is to make similar apparatuses to spread the observation network.

Design of protection and control scheme for hybrid nanogrid

Nanogrid is “The new ray of hope” for people living in remote isolated locations as well as where power supply reliability is poor. A nanogrid is a small power capacity distribution system with the ability to operate standalone or with a utility grid. It consists of local power production supplying local loads and energy storage systems. In this paper, an innovative inverter design is presented, which converts the power in a single stage. It is superior to the traditional two-stage inverter system and can supply hybrid loads (AC and DC loads) with a single input. System AC and DC bus voltages are regulated under both steady-state and dynamic load variation conditions in the nanogrid. Simulation results are presented which confirm the suitability of the inverter and its control strategy for a hybrid nanogrid system.

INVESTIGATION PERFORMANCE OF PICO HYDRO WATER PIPE TURBINE

The flow of water in the pipeline for household needs is a source of energy that can generate electrical energy through Pico hydro turbines or small-power water turbines. The experiment has been conducted on a 10 Watt Pico hydro turbine mounted on a water pipe against changes in water flow discharge. The turbine performance analysis is conducted experimentally (actual) and theoretically (ideal). The analysis results showed the greater the discharge flow, the greater the power generated by the turbine. In tests with a maximum discharge of 8.9 l/min, the actual power of 1.121 Watts, the torque of 0.005 Nm with a rotation speed of 2146.8 rpm and efficiency of 12.59%; while the ideal power is based on Euler turbine equation of 4.2 Watts and torque of 0.016 Nm. So, the maximum turbine power that can be generated is only 26.67% ideal. Efficiency turbine decreases with increased discharge; in this test, the maximum efficiency was 24.89% at 5.8 L/min flow discharge.

Hybridization of non-manageable renewable energy plants with compressed or liquefied air storage

. A kind of energy storage proceeding from renewable sources is presented. It has been studied the storage, in the form of Compressed Air Energy Storage Systems (CAES) or Liquefied Air Energy Storage Systems (LAES) of the renewable electricity that, at the time it is generated, it is not delivered to the network because of technical or economic reasons, or saturation. The possibility of using an artificial storage system allows the installation not to be conditioned by the availability of a natural reservoir. This article focuses on the use of artificial storage systems, mainly for small power wind farms (about 30 kW), so storage systems will alternatively be called CAES or SCAES and LAES or SLAES (S from “small”) CAES systems advantages and disadvantages of each different thermodynamic cycle are studied. One of CAES systems higher limitations is the huge volume needed to store air mass enough. Instead of storing gaseous phase air, much more energy density can be accumulated by storing air in liquid phase (LAES). LAES system functioning is similar to CAES one. Liquid air is produced in an air liquefying plant when there is an excess of energy or it is not interesting to drop it into the network Some LAES systems advantages are storage volume reduction for the same energy density and the possibility of storing at about atmospheric pressure.