2. Main technical characteristics of the LSF

condition of the mirrors, angular inaccuracies of the light-reflecting mirrors, reflection coefficient of the mirrors, condition of the solar sensors, etc.

A Guide to Small-Scale Energy Harvesting Techniques

700 W/cm2

of the LSF.

of LSF.

Figure 1.

112

General view of the France furnace.

summer of 1987 [9, 10].

high-tech industry.

The Materials Science Institute of the Academy of Sciences of the Republic of Uzbekistan operates a large solar furnace of 1000 kW thermal power (LSF). It is a composite optical and mechanical complex with automatic control systems, comprising the heliostat field (62 heliostats), paraboloidal concentrator (with 1906 m2 midship section area-projection of the surface of the concentrator on the plane), and technological tower. Highly concentrated solar radiation, with energy density up to

technological tower. A set of specialized testing facilities are developed at the LSF, having not analogues in terms of a number of parameters either in home or foreign practice. Note that the abbreviation BSF (Big Solar Furnace) is often used instead

The LSF was put into operation as an experimental-industrial one, in the

During Soviet times this unique solar furnace was the leading facility of militaryindustrial complex for testing of different materials and equipment to the action of concentrated solar radiation and for development of advanced ceramic materials for

In connection with the change of research direction (from military to peaceful), the fields of technology of engineering ceramics, fireproof materials of wide range of applications, particularly for metallurgy, oil and gas complex, power engineering, machine building, and chemical industries became the major directions of use

Scientists in Uzbekistan have achieved significant results in high-temperature solar technologies. More than 150 compositions of various oxide materials having unique properties and serving as the basis for functional, structural, and highrefractory ceramics have been developed and synthesized at the LSF, and their thermophysical and other characteristics have been studied. The LSF is a unique instrument for field studies of high-temperature processes, i.e., on the synthesis and

Note that such a furnace was previously commissioned in Odeillo, France. This 1000 kW solar furnace was completed in 1970 (Figure 1). The furnace contains 63 orientated mirrors (heliostats), each of 45 m2 surface, with 180 single mirror

heat treatment of materials and study of their properties.

, may be nowadays created in the focal region of the LSF, located in the

The LSF as noted above represents a complex optomechanical aggregate with automatic control systems consisting of a heliostat field and paraboloid concentrator, which form a high-density radiation flux in the focal zone of the concentrator. The furnace is located 50 km from Tashkent, in the Parkent District. The geographical location is 41.32°N, 69.74°E; its altitude above sea level is 1050 m.

The LSF heliostat field is formed by 62 heliostats located on the smooth slope of a mountain (slope 13°) in a checkerboard pattern arranged on 8 terraces. All 62 heliostats of the LSF have a similar structure and dimension. The reflecting surface of the heliostat with dimensions of 7.5 6.5 m is flat and composite and consists of 195 facets with dimensions of 0.5 0.5 m and a thickness of 6 mm.

Figure 2. (a) Overview diagram of LSF and (b) general view of the LSF.

The reflecting surface of the concentrator is a rectangular-stepped cutting of a paraboloid of revolution with a focal distance of 18 m. The height of the midsection of the concentrator is 42 m, and the width is 54 m. The total area of the midsection of the reflecting surface is 1906 m<sup>2</sup> . The concentrator consists of 214 blocks. 50 rhomb-shaped facets with sides of 447 mm and different apex angles are installed on each block. The thickness of mirrors is 5 mm.

possible to significantly extend its functional capabilities. The new HACS differs fundamentally from the old one: modern microprocessor circuits are used in the element bases, achievements in modern information technologies have been implemented, reliable operation is ensured, and it has high accuracy and flexibility for the required processing modes [19]. The operational efficiency of the new system has successfully been tested on one heliostat, and efforts on transferring the system to other heliostats are planned (2019-2020). As a result, the LSF will have

Thousand kW High-Temperature Solar Furnace in Parkent (Uzbekistan) – Energetical…

It should be noted that the third modernization of the control system of the

Furthermore, any complex processing device without a system for monitoring

efficiently and reliably. In this respect, the LSF is equipped with modern devices to measure the density of concentrated solar energy and the temperature of the studied materials and devices to control the behavior of the high-temperature processes. They include a high-temperature pyrometer for remote measurement of the temperature of materials (IMPAC IGA 12,Tmax = 3500°C), a thermal imager (FLIR A655), various radiometers, photometers, digital thermometers, a computer vision system (developments of the Institute of Materials Science - IMS)

Thus, the LSF, in addition to an environmentally friendly melting furnace, is a

unique research tool for high-temperature studies, which has some important

4.Sixty-two heliostats, which makes it possible to control the focal energy

5. The HACS makes it possible to flexibly control movement of the heliostats.

8.The ability to measure and control the optical energy condition of the furnace.

4. Calculation of the optical-energetical characteristics of the LSF: the

In the helio-engineering practice, different techniques for evaluation of energetical characteristics of mirror concentrating systems (MCS) are employed, depending on the purpose, demanded accuracy, etc [23–29]. However, if a big MCS

as a solar furnace in Odeillo (France) or Large Solar Furnace near Tashkent (Uzbekistan) is concerned, there are specific features which must be taken into

An important feature of a big-scale MCS is the use of multi-heliostat system to create illumination field on its focal zone. Thanks to this feature, there is a

advantages compared to other high-temperature solar furnaces:

2. High levels of solar radiation concentration, ≈ 4500–10,000.

3. Large size of the focal spot of the furnace, ≈ 80–100 cm.

6. Simulation of 62 aperture-specific concentrators.

7. Control of the behavior of technological processes.

1. High power of the furnace, up to 1 MW.

heliostats of the French furnace has also been completed recently [22].

and measuring its operating parameters and characteristics cannot function

some new possibilities for practical use.

DOI: http://dx.doi.org/10.5772/intechopen.83411

and etc.

distribution.

general approach

account.

115

In total, there are 22,790 facets; the total area of the reflecting mirrors (facets) is about 5200 m<sup>2</sup> ; the heliostat field, process tower, and concentrator occupy approximately 2 ha of ground area. Technical characteristics of the installation are also described in the works [9, 10, 12, 13].

The general pattern of the device is shown in Figure 2a and the general view of the installation were shown in Figure 2b.
