Solar Trough Field System

Abstract

A solar trough field system according to the invention comprises multiple parabolic reflectors; a thermal receiver tube, center of which coincides with the focus of the parabolic reflectors and which consists of a metal heat receiving pipe (1) and a glass tube (2) which are nested (the glass tube surrounds the metal heat receiving pipe from outside); a ‘vacuum seal and glass tube connector system’ (E) which connects the glass tubes (2) and the thermal heat receiving pipe (1) to each other; a rotating support unit (21), which connects the parabolic panel to the glass tube connector system (E) and provides the thermal receiver tube (1) to stay stationary while the parabolic panel is rotating around it; ‘flexible expansion unit’ (29) located at the end of each parabolic trough unit which provides vacuum seal while the Heat Receiving Pipe (1) is moving due to heat expansion; and a vertical loop (52) located at the discharge side of the parabolic unit, which can be used instead of water separator and which also provides the heat expansion of the Heat Receiving Pipe (103).

Description

TECHNICAL FIELD[0001]This invention relates to developments on parabolic trough-shaped collectors which concentrate the sunlight on an axis of focus, converting it into other energy forms such as heat and electricity.PRIOR ART[0002]Currently, trough collectors (solar trough field system) are used to collect the sun's energy in order to obtain electricity and heat there from. These systems comprise trough-shaped long parabolic reflectors, thermal receiver tubes which are placed on the focus of the reflectors where beams coming from the reflector are collected and in which a fluid exists, and a rotating mechanism which aligns the reflectors to the sun. The beams coming to the reflectors which are directed towards the sun are reflected and collected on the thermal receiver tube which is located on the focus of the reflector. Thermal receiver tube is provided with two nested tubes where a vacuum setting is located in the space there between. A fluid, which provides the heat transfer, is...

AI Technical Summary

Benefits of technology

[0017]A “vacuum seal and glass tube connector system” which allows the Heat Receiver pipe to expand and move freely within and independent of the glass tubes, provides a vacuum seal and provides support for the entire Heat Receiver Element;

[0027]Another object of the invention is to use “glass tube connection system” to provide a continuous vacuum chamber for the full length of the parabolic through unit, allowing for the creation and repeated maintenance of the vacuum from a single valve located at either end of the parabolic trough unit, eliminating the need for the currently used “getter” sticks to absorb Hydrogen.

Problems solved by technology

The existing Solar through Field type of Thermal Energy technologies have some design problems which cause thermodynamic efficiency losses and increase fabrication, installation, operation and maintenance costs.

These design problems are:

The most fundamental problem of this system is that the thermal receiver tubes which are made of a fragile material are movable.

The thermal receiver tubes which are subjected to the torque loads have a higher possibility of breaking.

On the other hand, it is understood that the flexible hose connection is not a safe system since the temperature of the fluid which is transferred within the thermal receiver tube is 300-500° C. In addition, it has been obtained from the field observations that the truss structure, which supports the parabolic mirrors, is also weak against the torque and the moment loads acting due to the drive unit of the system and the wind.

Because of these loads, the parabolic reflectors are frequently broken, thus causing the operating costs to increase.

Even though hot oil does not have the dynamics of the steam, these hoses still burst occasionally, spilling oil all over the mirror lined parabolic troughs.

However this two stage operation results in thermodynamic losses up to 15%.

Although the truss system which is developed with EUROTROUGH is safer than the system of LUZ, it could not completely eliminate the breaking problem of the thermal receiver tubes.

In addition, it has been also revealed from the field observations that the hot fluid frequently leaks out from these connections of the thermal receiver tubes comprising rotary joint connection points.

Another design problem existing in current technologies can be seen from FIG. 2, which shows the connection between the glass tube (102) and the metal heat receiving pipe (103).

Thus it gradually weakens the special connection to the glass tube.This metal expansion piece inevitably conveys some of the vibration and torque created by the metal parts to the glass tubes, causing them to break.

A further design problem exists in high pressure separators (can be seen in FIG. 24).

However this increases system inefficiency, as well as adds to the system cost.

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