Solar Panel Mounting: Pushing the Boundaries of Energy
Efficiency for Solar Panels
The VEX sustainable design challenge presented the robotics club at our school
with a challenging, and fun way to apply our skills in CAD, physics, math, and
engineering. The first step in the design process required taking the challenge as a
request for proposal (RFP). By doing so we can derive a requirements document for
the robot based on the needs of the design challenge. The first things to determine
were the absolute necessities of the robot, and declare these in shall statements.
- The robot shall be designed using Autodesk CAD software
- The robot shall achieve one or more sustainability goals
- The robot shall use a minimal amount of materials
- Etc.
After determining the absolute necessities of the robot, we clarified the vague terms
made in the above statements. There is no specific definition for sustainability goal,
so it was our obligation to define that. It is our belief that there is a significant
problem with the world’s energy needs. The world has constantly used fossil fuels
as a source of energy, releasing more and more CO2 into the Earth’s atmosphere.
The amassing CO2 causes global warming, and the ever-looming threat of extinction
is a cause for concern. Thus, the need for an efficient source of “clean” energy
emerged. The goal for our team was to design a robot or machine that can efficiently
accomplish the goals presented, while also engineering a reliable working product.
Thus we decided to provide a source of clean energy through solar power. In well-lit
areas, solar power pays for itself within a year given the right panels. Innovations in
solar panels have progressed steadily throughout the past decade, but there has
never been an innovation in the mounting of solar panels. While material efficiency
is a top priority for mounting devices, we can still push the boundaries. The
mounting device that we propose will track the sun with the VEX light sensor, and
adjust the panel for optimal conditions. This allows a solar panel to maximize its
time vs. energy-attained function, pushing efficiency over the top. Our mounting
device is also designed to be lightweight and long lasting; with the use of steel in the
hopes the steel reaches infinite life. We as a team accomplish these goals through
the use of the various CAD tools at our disposal. After determining what we
specifically wanted to design, we made sketches, free-body diagrams, and general
ideas for the project. With sketches and free-body diagrams at our disposal we
began to actually make the model in Inventor. There were many tools and ideas that
the sustainability workshop introduced to us as a team. Among them was the FEA
package for CAD, and the belief that there needs to be math done on a design before
actually modeling. One of the articles in the sustainability workshop introduced
some of the designs for a previous challenge. It pointed out the second place design,
a machine that produced energy through a slowly descending weight. While this
design was practical, it turns out the concept is physically impossible. Subsequently,
our team wanted to make a reliable working product, which had actual industrial
use. We accomplished this through analysis using the produced free-body diagrams,
specifically force analysis, statics analysis, and most importantly stress analysis.
With the Autodesk FEA analysis package, we were able to see the areas of highest
and least stress on our mounting device (given the forces on our panel from the
free-body diagrams), and could very easily determine which places needed less or
more support, adjusting till we maximized our material efficiency. The sustainability
workshop also taught us how to maximize the energy efficiency of our robot. In
almost any exchange of energy, there will be a loss from the final system. The
sustainability workshops tips on reducing friction in our mounting device, allowed
us to maximize the energy efficiency of our device. The sustainability workshop also
taught us about CFD analysis, and how heat transfer can affect energy efficiency.
While we were unable to complete this analysis, we know that it would be helpful to
do, especially because a solar panels energy intake is almost directly correlated to
heat transfer. The materials section of the site helped greatly as well in designing a
green product. Finally, the constrain tool was the main reason we could do all of this
analysis, and without the proper constraints on our models, we had many
inaccuracies.