Compound Solar Collector with Multi-Stage Pyramidal Concentration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current solar energy collection systems face challenges in achieving high efficiency and low costs due to sensitivity to sun movement, optical inefficiencies, high manufacturing costs, and size constraints, limiting their widespread adoption.
Innovation Solution
A compound solar collector system utilizing concatenated tapered pyramidal structures with multiple internal reflections, which reduces sensitivity to sun movement and allows for low-cost tracking, increased efficiency under cloudy conditions, and lower manufacturing costs, while maintaining high energy collection capabilities.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If traditional parabolic mirror collectors or Fresnel lenses are used for solar concentration, then high concentration ratios can be achieved, but the systems require highly accurate and expensive feedback-controlled solar tracking mechanisms
Solution Approach 1:
The patent divides the single large parabolic mirror into multiple smaller planar mirror segments arranged in a specific geometric configuration. These segmented mirrors work together to concentrate sunlight onto the receiver, achieving the same concentration effect as a large parabolic mirror but with simpler, less expensive individual components that are more tolerant of tracking inaccuracies
Solution Approach 2:
Each planar mirror segment is designed with specific local optical properties and orientations that contribute to the overall concentration function. The mirrors are positioned and angled to reflect sunlight from different parts of the sky dome onto the receiver, with each segment optimized for its specific role in the concentration process
2Ease of manufacture
If flat-plate solar PV panels are used, then installation is simple and costs are moderate, but the active area must essentially equal the PV material area resulting in high costs of $2-$5 per watt
Solution Approach 1:
The patent combines concentrating optics (planar mirrors) with PV cells in a hybrid system where the mirrors concentrate sunlight onto a smaller area of PV material. This merging of optical concentration with photovoltaic conversion allows the same PV area to generate more power, effectively reducing the cost per watt while maintaining ease of installation
Solution Approach 2:
The system adds the spatial dimension of optical concentration by positioning mirrors at specific angles and distances above the PV cells. This vertical arrangement allows sunlight to be concentrated from a larger aperture area onto a smaller receiver area, increasing energy density without expanding the PV material footprint
3Productivity
If thin-film PV materials are used to reduce base material cost, then cost decreases but module efficiency is reduced
Solution Approach 1:
The concentrating mirror system pre-concentrates sunlight onto the thin-film PV cells before the light reaches the active material. This preliminary concentration compensates for the lower efficiency of thin-film materials by delivering higher photon density to the cells, thereby maintaining overall system performance while using cheaper PV material
Solution Approach 2:
The system changes the intensity parameter of incident sunlight by using optical concentration to increase the photon flux density on the PV cells. This parameter change allows thin-film materials, which have lower quantum efficiency, to still generate adequate power output by receiving more concentrated light
4Use of energy by moving object
If large area parabolic reflectors are used for solar concentration, then high energy concentration is achieved, but the systems become large and bulky requiring vast desert floor space
Solution Approach 1:
The patent arranges multiple planar mirror segments in a nested or stacked configuration where smaller mirrors are positioned above and around a central receiver. This nested arrangement achieves high concentration ratios in a compact vertical footprint, dramatically reducing the horizontal land area required compared to large-area parabolic reflectors
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 compound solar collector system achieves significant efficiency gains and cost reductions, enabling effective energy conversion even under hazy conditions and tolerating geometric flaws, making it suitable for residential and industrial applications with reduced land and material requirements.
Implementation Method 1
a compound collector system formed of a plurality of concatenated collectors, each of which utilizes multiple internal reflections of light passing down a tapered, pyramidal-type structure made of highly-reflective and planar mirrored surfaces
Implementation Method 2
tapered, pyramidal-type structure made of highly-reflective and planar mirrored surfaces
Data Source
AI summary
A solar collector is formed as a compound arrangement of a multiple number of tapered, pyramidal-type structures. This forms an N-stage solar collector, each stage providing a degree of concentration and thus forming an arrangement that is smaller than a single stage collector (while achieving the same amplification factor). The stages are arranged in tandem along a common optical axis, with the output of the first stage becoming the input for the second stage, and so on. It was found that a reduced number of reflections is required, reducing the loss of the overall system.