Executive Summary
The colossal consumption rate of the limited amount of fossil fuel remaining creates significant problems for the environment and the future of energy. To ensure that there will be a sufficient amount of energy to continuously drive the world’s economy and food supply, the development of and transition to a more abundant renewable source of energy becomes necessary. The challenges of converting to a new energy resource should be tackled today in order to prepare for the eminent depletion of fossil fuel.
Annually, the Earth receives approximately 8,000 times more solar energy than the amount of energy consumed globally, proving solar power to be a viable candidate as the next primary energy supplier. However, the variable nature of its power output due to different cloud coverage stands as a large scale engineering obstacle that hinders the widespread penetration of solar power into the energy market. Therefore, it is essential to accurately forecast available solar resources through the tracking of cloud movement, which can be accomplished with a grid of ambient light sensors to sense a cloud’s shadow as it sequentially shades different sensors.
The first prototype of the ground-based cloud detection device was built by Philip Pan and John Ramparo at the University of California, San Diego (UCSD) under the guidance of the associate director of UCSD’s Center of Energy Research (CER), Dr. Jan Kleissl.
Figure 1: Previous Ground Sensor Array
The primary objective of this research project was to optimize the first prototype by scaling down its size and creating a higher quality cloud speed and direction sensing system. This includes having higher sampling rates, creating a weatherized housing enclosure, and processing stored data on-board before relaying measurements to a centralized computer. The design and fabrication of the new and improved prototype was conducted by the collaboration of four senior level undergraduate engineering students: Andy Chen, Jeff Head, Tyler Capps, and Victor Fung.
Figure 2: Current Ground Sensor Array
The cloud velocity measurement system was successful in its attempt to reduce the size of the previous prototype while exceeding its capabilities. Performing a known velocity test, the on-board processing provided calculations corresponding to speed and direction errors of 0.85% and 0.00%, respectively. This proved its ability to accurately measure both cloud speed and direction as well as provide real time on-board processing.
The system is in the final design phase and with a few adjustments and improved robustness, will be ready for the market. Some of these adjustments include: Implementing an internal battery with solar power as a recharging agent, utilizing multiple 5-Volt regulators to evenly disperse power distribution, using XBee Pro transceivers (with antenna) to achieve longer range connections, and further optimize the code to gain an even faster sampling rate.