[001] REFLECTOR UNIT FOR A LINEAR FRESNEL REFLECTOR SOLAR
ENERGY COLLECTOR SYSTEM
[002] FIELD OF THE INVENTION
[003] Embodiments of the present invention in general relate to a
linear fresnel reflector solar energy collector system, and in particular
relates to a reflector unit for the linear fresnel reflector solar energy
collector system having a configuration that reduces the weight of a
reflector support structure and its manufacturing cost.
[004] BACKGROUND OF INVENTION
[005] Solar power generation has been considered a viable source to
help provide for energy needs in a time of increasing consciousness of
the environmental aspects of power production. Solar energy
production relies mainly on the ability to collect and convert energy
freely available from the sun and can be produced with very little
impact on the environment. Solar power can be produced without
creating radioactive waste as in nuclear power production, and without
producing pollutant emissions including greenhouse gases as in fossil
fuel power production. Solar power production is independent of
fluctuating fuel costs and does not consume non-renewable resources.
[006] Solar power generators generally employ fields of controlled
mirrors, to gather and concentrate sunlight on a receiver to provide a
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heat source for power production. A solar receiver typically takes the
form of a panel of tubes conveying a working fluid therethrough.
Previous solar generators have used working fluids such as molten salt
because It has the ability to store energy, allowing power generation
when there is little or no solar radiation, such as at night time. The
heated working fluids are typically conveyed to a heat exchanger
where they release heat into a second working fluid such as air, water,
or steam. Power is generated by driving heated air or steam through a
turbine that drives an electrical generator.
[007] Such conventional methods and systems for solar power
generation have generally been considered satisfactory for their
Intended purpose. However, there is still a need in the art for systems
and methods for solar power generation that allow for improved
efficiency, decreased heat loss, and lower manufacturing costs.
[008] SUMMARY OF INVENTION
[009] According to an embodiment of the present invention there is
provided a direct saturated and superheated steam generating linear
fresnel reflector solar energy collector system having an configuration
that helps to achieve higher operating temperature and pressure with
improved optical and thermal efficiencies.
[010] According to an embodiment of the present invention there is
provided a direct saturated and superheated steam generating linear
fresnel reflector solar energy collector system wherein the
components of the linear fresnel reflector solar energy collector
system are designed for optimization of cost and performance.
[ O i l ] According to an embodiment of the present invention there is
provided a direct saturated and superheated steam generating linear
fresnel reflector solar energy collector system comprises a reflector
unit wherein the supporting structures for reflector unit have been
optimized for ease of manufacturing and higher productivity.
[012] According to an embodiment of the present invention there is
provided a direct saturated and superheated steam generating linear
fresnel reflector solar energy collector system. The direct saturated
and superheated steam generating linear fresnel reflector solar energy
collector system includes one or more primary reflectors, and each of
the one or more primary reflectors are arranged in parallel to each
other.
[013] According to an embodiment of the present invention there is
provided a direct saturated and superheated steam generating linear
fresnel reflector solar energy collector system includes one or more
primary reflectors, wherein the each of the one or more primary
reflectors are arranged in parallel to each other and placed at a
predefined distance apart from each other, closer to the ground.
[014] According to an embodiment of the present invention there is
provide a direct saturated and superheated steam generating linear
fresnel reflector solar energy collector system includes one or more
primary reflectors placed at a pre-defined distance from each other
wherein the distance is calculated such that the shadow of the one or
more primary reflectors is not casted on its adjacent primary reflectors
of the one or more primary reflectors for a particular hour angle.
[015] According to an embodiment of the present invention there is
provided a direct saturated and superheated steam generating linear
fresnel reflector solar energy collector system includes one or more
primary reflectors that are mounted on at least one axle.
[016] According to an embodiment of the present invention there is
provided a direct saturated and superheated steam generating linear
fresnel reflector solar energy collector system includes one or more
primary reflectors that are mounted on at least one axle that rest on
one or more rollers wherein the one or more rollers facilitates and
supports axial rotation.
[017] According to an embodiment of the present invention there is
provided a direct saturated and superheated steam generating linear
fresnel reflector solar energy collector system includes one or more
primary reflectors mounted on at least one axle that rest on one or
more rollers wherein the one or more rollers are mounted on steel
girders.
[018] According to an embodiment of the present invention there is
provided a direct saturated and superheated steam generating linear
fresnel reflector solar energy collector system includes one or more
primary reflectors mounted on at least one axle, and wherein the axial
rotation of the at least one axle about the center of mass reduces the
electric power required to rotate the one or more primary reflectors.
[019] According to an embodiment of the present invention there is
provided a direct saturated and superheated steam generating linear
fresnel reflector solar energy collector system includes a reflector unit.
The reflector unit includes one or more primary reflectors, wherein the
one or more primary reflectors are arranged in parallel to each other.
The reflector unit further includes at least one axle wherein the one or
more primary reflectors are mounted on the at least one axle for axial
rotation. The reflector unit further includes a reflector support
structure for supporting the one or more primary reflectors on the at
least axle. The reflector support structure includes a torque tube for
bearing the weight of the one or more primary reflectors; one or more
former sheets wherein the one or more former sheets are attached
onto the torque tube and wherein each of the one or more former
sheets is attached to a pre-bent aluminum rib of one or more
aluminum ribs.
[020] According to an embodiment of the present invention there is
provided a direct saturated and superheated steam generating linear
fresnel reflector solar energy collector system wherein the torque tube
is formed from a galvanized steel material.
[021] According to an embodiment of the present Invention there is
provided a direct saturated and superheated steam generating linear
fresnel reflector solar energy collector wherein the torque tube bears
the total dynamic and static loads of the one or more primary
reflectors.
[022] According to an embodiment of the present invention there is
provided a direct saturated and superheated steam generating linear
fresnel reflector solar energy collector system wherein the one or
more aluminium ribs serve to hold the one or more primary reflectors
in place and provide strength to withstand the hail impact and the
wind load.
[023] According to an embodiment of the present invention there is
provided a direct saturated and superheated steam generating linear
fresnel reflector solar energy collector system wherein the one or
more former sheets are welded on to the torque tube at intervals such
that the alignment of each former sheet of the one or more former
sheets with respect to each other is maintained equally.
[024] According to an embodiment of the present invention there is
provided a direct saturated and superheated steam generating linear
fresnel reflector solar energy collector system wherein each of the one
or more aluminium ribs are mounted to the corresponding former
sheet of the one or more former sheets such that the planarity of each
of the one or more aluminium ribs with respect to the each of the one
or more former sheets is maintained.
[025] According to an embodiment of the present invention there is
provided a direct saturated and superheated steam generating linear
fresnel reflector solar energy collector system wherein a radius of
curvature for each of the one or more primary reflectors is set by cold
forming each of the one or more aluminium ribs to the required
curvature.
[026] According to an embodiment of the present invention there is
provided a direct saturated and superheated steam generating linear
fresnel reflector solar energy collector system wherein the cold
forming of each of the one or more aluminium ribs is performed prior
to mounting of each of the one or more aluminium ribs on to the
torque tube.
«
[027] According to an embodiment of the present invention there is
provided a direct saturated and superheated steam generating linear
fresnel reflector solar energy collector system wherein one or more
support end plates are welded at the either ends of the torque tube.
[028] According to an embodiment of the present invention there is
provided a direct saturated and superheated steam generating linear
fresnel reflector solar energy collector system wherein an axle plate is
fastened to each of the one or more support end plates.
[029] According to an embodiment of the present invention there is
provided a direct saturated and superheated steam generating linear
fresnel reflector solar energy collector system wherein the one or
more primary reflectors are directly glued to the one or more
aluminium ribs.
[030] According to an embodiment of the present invention there is
provided a direct saturated and superheated steam generating linear
fresnel reflector solar energy collector system including at least one
linear cavity receiver housing a single evacuated tube collector and
one or more primary reflectors, wherein the one or more primary
reflectors concentrates the sunlight on to an ETC and thereby
increasing the concentration ratio.
[031] According to an embodiment of the present invention there is
provided a direct saturated and superheated steam generating linear
fresnel reflector solar energy collector system wherein a ETC is
clamped such that the position of the ETC is fixed in the cross
sectional plane and allowed to expand due to thermal expansion in a
longitudinal direction along the length of the ETC.
[032] According to an embodiment of the present invention there is
provided a direct saturated and superheated steam generating linear
fresnel reflector solar energy collector system for generating useful
heat in the form of saturated or/and superheated steam by
concentrating sunlight on to a single row of one or more evacuated
receiver tube collectors housed along with one or more primary
reflectors.
[033] According to an embodiment of the present invention there is
provided a direct saturated and superheated steam generating linear
fresnel reflector solar energy collector system including a configuration
having a single row of evacuated receiver tube collectors and one or
more primary reflectors that increases the concentration ratio (Total
mirror aperture width to absorber tube aperture width) and hence the
operation parameters (temperature and pressure of steam).
[034] According to an embodiment of the present invention there is
provided a direct saturated and superheated steam generating linear
lo
fresnel reflector solar energy collector system including an absorber
tube that is maintained in vacuum during operation hence the heat
loss is reduced and the efficiency is increased considerably.
[035] According to an embodiment of the present invention there is
provided a direct saturated and superheated steam generating linear
fresnel reflector solar energy collector system including a single row of
evacuated receiver tube collector configuration that simplifies the
process line and instrumentation thereby reducing the cost and
operation procedure.
[036] These and further aspects which will be apparent to the expert
of the art are attained by a direct saturated and superheated steam
generating linear fresnel reflector solar energy collector in accordance
with the main claim.
[037] BRIEF DESCRIPTION OF THE DRAWINGS
[038] So that the manner in which the above recited features of the
present invention can be understood in detail, a more particular
description of the invention, briefly summarized above, may be had by
reference to embodiments, some of which are illustrated in the
appended drawings. It is to be noted, however, that the appended
drawings illustrate only typical embodiments of this invention and are
II
therefore not to be considered limiting of its scope, for the invention
may admit to other equally effective embodiments.
[039] Figure 1 illustrates a perspective view of a Linear Fresnei
Reflector (LFR) solar energy collector system according to an
embodiment of the present invention;
[040] Figure 2 illustrates a perspective view of a reflector unit of a
Linear Fresnei Reflector (LFR) solar energy collector system according
to an embodiment of the present invention;
[041] Figure 3 illustrates a perspective view of the various
components of a reflector unit of a Linear Fresnei Reflector (LFR) solar
energy collector system according to an embodiment of the present
invention;
[042] Figure 4 illustrates a front view of a reflector unit of a Linear
Fresnei Reflector (LFR) solar energy collector system according to an
embodiment of the present invention; and
[043] Figure 5 illustrates a side view of a reflector support structure of
a Linear Fresnei Reflector (LFR) solar energy collector system
according to an embodiment of the present invention.
\i
[044] To facilitate understanding, identical reference numerals have
been used, where possible, to designate identical elements that are
common to the figures. It is to be noted, however, that the appended
drawings illustrate only typical embodiments of this invention and are
therefore not to be considered limiting of its scope, for the invention
may admit to other equally effective embodiments.
[045] DETAILED DESCRIPTION OF THE DRAWINGS
[046] Figure 1 to 5 illustrates various views of a Linear Fresnel
Reflector (LFR) solar energy collector system 100 according to an
embodiment of the present invention. The Linear Fresnel Reflector
(LFR) solar energy collector system 100 includes a linear cavity
receiver 102. The linear cavity receiver 102 houses a secondary
reflector 104 and an evacuated absorber tube collector (single tube
collector) 106.
[047] The Linear Fresnel Reflector (LFR) solar energy collector system
100 further includes a reflector unit. In an embodiment, the reflector
unit includes one or more primary reflectors 108 are arranged in
parallel with respect to each other, and each of the one or more
primary reflectors 108 are placed at a proximate distance (a gap) with
respect to the ground. The gap is so chosen that the shadow of the
one or more primary reflectors 108 is not casted on adjacent primary
13
reflectors of the one or more primary reflectors 108 at least for a
particular hour angle.
[048] The Linear Fresnel Reflector (LFR) solar energy collector system
100 further includes a reflector support structure that further includes
a torque tube for bearing the weight of the one or more primary
reflectors 108. The torque tube is configured to act as a support
structure for supporting the one or more primary reflectors 108. In
the present embodiment, the torque tube is made of galvanised steel
but in any other embodiment of the present invention the torque tube
can be made of any suitable material without moving out from the
scope of disclosed embodiments. The torque tube in the present
invention acts as a main strength element for bearing the load of the
reflector material and further bears the total dynamic and static loads.
[049] In the present invention, two types of structures using the
torque tube with different steel frame designs are proposed. In one
embodiment, the reflector support structure serves to hold the
reflector material in place and subsequently provides sufficient
strength to withstand the hail impact and wind load.
[050] In another embodiment, the direct saturated and superheated
steam generating linear fresnel reflector solar energy collector system
100 includes a torque tube based reflector support structure. Herein,
the reflector support structure includes one or more aluminum ribs
11
201 and one or more former sheets 202. The one or more aluminium
angle ribs 201 are pre-bent to the required radious of curvature of
each primary reflector 200 of the one or more primary reflectors 108
by a cold forming process. It is to be noted that any other technology
known in the art may be utiized in order to pre bent the one or more
aluminum ribs 201 into the desired radious of curvature without
moving out from the scope of the disclosed embodiments.
[051] After the cold forming process is completed, each of the one or
more pre-bent aluminium ribs 201 after are then mounted to the
corresponding former sheet of the one or more former sheets 202
such that the planarity of each of the one or more aluminium ribs 201
with respect to the each of the one or more former sheets 202 is
maintained. Therafter, the one or more former sheets 202 are welded
on to the torque tube at intervals such that the alignment of each
former sheet of the one or more former sheets 202 with respect to
each other is maintained equally.
[052] After the assembling and configuration of the reflector support
structure, the one or more primary reflectors 108 are then directly
glued to the one or more aluminium angle ribs 201 and therefore
takes the shape of the one or more aluminium ribs 201 permanently.
It is to be noted that in any other embodiment of the present
\s
invention, the one or more primary reflectors 108 may be attached or
fastened to the one or more aluminium ribs 201 by any suiatble
attachment/ fastening means without moving out from the scope of
the dislcosed embodiments. This simplicity of the configuration
reduces the weight of the reflector support structure and also the
manufacturing cost in making the refector support structure.
[053] The Linear Fresne! Reflector (LFR) solar energy collector system
100 further includes an axle. The one or more primary reflectors 108
are mounted on an axle. The axle further rest on one or more rollers
300 for supporting axial rotation and wherein the one or more rollers
300 are further mounted on steel girders 205. It is to be noted that
the girders 205 may be made of any material other than steel in
another embodiment of the present invention without moving out from
the scope of the disclosed embodiments. The reflector support
structure is configured for supporting the one or more primary
reflectors 108 on the axle. In an embodimet, one or more axle plates
301 are provided about the central line along the center of mass of
the one or more primary reflectors 108, and hence the turning torque
and power required for axial rotation is reduced. The one or more axle
plates 301 are fastened to each of one or more end support plates
203, wherein the one or more support end plates 203 are welded at
the either ends of the torque tube.
1^
[054] While the foregoing is directed to embodiments of the present
invention, other and further embodiments of the invention may be
devised without departing from the basic scope thereof, and the scope
thereof is determined by the claims that follow.
)1

We Claim 0
1. A linear fresnel reflector solar energy collector system
comprising:
a reflector unit, the reflector unit comprising:
one or more primary reflectors, wherein the one or more
primary reflectors are arranged in parallel to each other;
at least one axle, wherein the one or more primary
reflectors are mounted on the at least one axle for axial
rotation; and
a reflector support structure for supporting the one or
more primary reflectors on the at least axle, wherein the
reflector support structure comprises:
a torque tube for bearing the weight of the one or
more primary reflectors;
one or more former sheets, wherein the one or more
former sheets are attached onto the torque tube,
and wherein each of the one or more former sheets
is attached to a pre-bent aluminum rib of one or
more aluminum ribs.
|8
• ^
"Si*"
2. The linear fresnel reflector solar energy collector system of claim
1, wherein the one or more primary reflectors are placed at a
pre-defined distance a part, closer to the ground.
3. The linear fresnel reflector solar energy collector system of claim
2, wherein the pre-defined distance is calculated such that the
shadow of any of the one or more primary reflectors is not
casted on its adjacent primary reflectors of the one or more
primary reflectors for a particular hour angle.
4. The linear fresnel reflector solar energy collector system of claim
1, wherein the torque tube is formed from a galvanized steel
material.
5. The linear Fresnel reflector solar energy collector system of
claim 1, wherein the torque tube bears the total dynamic and
static loads of the one or more primary reflectors.
6. The linear fresnel reflector solar energy collector system of claim
1, wherein the one or more aluminium ribs serve to hold the one
or more primary reflectors in place and provide strength to
withstand the hail impact and the wind load.
7. The linear fresnel reflector solar energy collector system of claim
1, wherein the one or more former sheets are welded on to the
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M^ /\ /p 9
torque tube at intervals such that the alignment of each former
sheet of the one or more former sheets with respect to each
other is maintained equally.
8. The linear fresnel reflector solar energy collector system of claim
1, wherein each of the one or more aluminium ribs are mounted
to the corresponding former sheet of the one or more former
sheets such that the planarity of each of the one or more
aluminium ribs with respect to the each of the one or more
former sheets is maintained.
9. The linear fresnel reflector solar energy collector system of claim
1, wherein a radius of curvature for each of the one or more
primary reflectors is set by cold forming each of the one or more
aluminium ribs to the required curvature.
10. The linear fresnel reflector solar energy collector system of
claim 9, wherein the cold forming of each of the one or more
aluminium ribs is performed prior to mounting of each of the
one or more aluminium ribs on to the torque tube.
11. The linear fresnel reflector solar energy collector system of
claim 1, wherein one or more support end plates are welded at
the either ends of the torque tube.
ao
12. The linear fresnel reflector solar energy collector system of
claim 11, wherein an axle plate is fastened to each of the one or
more support end plates.
13. The linear fresnel reflector solar energy collector system of
claim 1, wherein the one or more primary reflectors are directly
glued to the one or more aluminium ribs.
14. The linear fresnel reflector solar energy collector system of
claim 1, wherein the at least one axle rest on one or more
rollers that facilitates and supports axial rotation.
15. The linear fresnel reflector solar energy collector system of
claim 14, wherein the one or more rollers are mounted on steel
girders.