Solar concentrator having a continuous parabolic reflective surface

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing parabolic solar concentrator systems face challenges in achieving a substantially continuous reflective surface due to support structure interference, complexity in construction, and damage to reflective surfaces during assembly, leading to optical losses and increased costs.

Innovation Solution

A parabolic solar concentrator system with a torsion bar and rib structure, where the axis of rotation is positioned behind the reflective dish, allowing the center of gravity to align with the axis, minimizing support interference and using removable brackets and clamps for easy assembly and damage prevention.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If metal sheets are used to create the reflective surface, then the cost is reduced, but the support structure becomes more complex to maintain the parabolic shape under wind stress

Engineering Contradiction:
Improvereflective surface continuityVSAvoidsupport structure complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The reflective surface is divided into multiple metal sheets that are joined together to form a continuous reflective surface. This segmentation allows the use of simpler, lighter metal sheets while achieving the required surface continuity and parabolic shape through proper joining and support.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Multiple metal sheets are merged together to form a continuous reflective surface. The sheets are joined using appropriate connections that maintain the parabolic geometry while allowing for thermal expansion and contraction, thereby achieving surface continuity without requiring an overly complex support structure.

Inventive Principle:
Principle #5Merging (Combining)

2Area of stationary object

If support pillars are positioned close to the reflective surface, then the structure is more compact, but they cause shading and interfere with the continuous reflective surface

Engineering Contradiction:
Improvesupport structure footprintVSAvoidoptical losses due to shading
Core Design Contradiction:
Area of stationary objectVSLoss of energy

Solution Approach 1:

The support pillars are positioned in a location that is dimensionally optimized to minimize their shadow on the reflective surface. By carefully selecting the position of the support pillars relative to the focal point and the reflective surface, the design reduces optical losses while maintaining structural compactness.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

3Weight of moving object

If the torsion bar is positioned close to the reflective surface, then the center of gravity is optimized, but it interferes with the support pillars and prevents optimal positioning

Engineering Contradiction:
Improvecenter of gravity positioningVSAvoidcollector positioning capability
Core Design Contradiction:
Weight of moving objectVSEase of operation

Solution Approach 1:

The torsion bar is positioned asymmetrically relative to the reflective surface, at a distance that optimizes both the center of gravity and the positioning capability. This asymmetric positioning allows the support pillars to be placed in optimal locations without interference from the torsion bar, enabling the collectors to reach the required +/- 120° positions.

Inventive Principle:
Principle #4Asymmetry

4Area of stationary object

If multiple reflective sheets are juxtaposed to cover larger dimensions, then the collector size is increased, but the gaps between sheets cause optical losses

Engineering Contradiction:
Improvecollector dimensionsVSAvoidoptical losses at sheet gaps
Core Design Contradiction:
Area of stationary objectVSLoss of energy

Solution Approach 1:

The metal sheets are pre-formed with appropriate curvature and joined together in a way that creates a continuous reflective surface. The joining method ensures that the gaps between sheets are minimized or eliminated, maintaining optical continuity across the entire reflective surface while allowing the collector to cover larger dimensions.

Inventive Principle:
Principle #10Preliminary action

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The system achieves a continuous reflective surface, reducing optical losses, simplifying construction, and enhancing maneuverability and efficiency by positioning the center of gravity close to the axis of rotation, thus minimizing structural interruptions and assembly risks.

Implementation Method 1

a plurality of reflective pieces of sheet metal, preferably substantially rectangular in shape, apt to reflect and concentrate the solar radiation towards the focus of the dish

Methodology Applied
Scientific EffectReflection: Reflection

Data Source

PatentEP3781880B1Solar concentrator having a continuous parabolic reflective surface
Publication Date: 2022.12.21 ENI SPA
  • EP3781880B1 patent drawingFigure 1
  • EP3781880B1 patent drawingFigure 2
  • EP3781880B1 patent drawingFigure 3

AI summary

Present invention relates to a system of parabolic solar concentrator (SCA) having a substantially continuous reflective surface aiming to maximize the efficiency of the parabolic solar concentrator and of its fabrication method. The system of the present invention allows the fabrication of a low cost parabolic solar concentrator, based on a torsion bar, ribs and a plurality of reflective pieces of sheet metal preferably covered with a reflective film. The parabolic solar concentrator according to a preferred embodiment allows the reduction of surfaces shading the reflective surface; another advantage is the lack of presence of supporting or movement elements (not including receiver tube components and supports) protruding in the concave side of the parabola, increasing the reflection efficiency and solar collection.