Introduction

Renewable energy is energy that can be obtained from natural sources,  which are not depleted but rather are replenished again when they are  used. Renewable energy is a form of energy  that can be found easily and is all around us. For example, sunlight, wind,  and hydropower are natural sources of renewable energy. 

Today,  renewable energy is one of the most crucial research areas since it has  many benefits and solutions for our environmental problems. The use of  single-use plastics is increasing and due to different human activities, both  using and acquiring energy causes different types of pollution. It is essential  for people to observe different types of renewable energy and ways of  obtaining it because renewable energy “produces no greenhouse gas  emissions from fossil fuels” and can result in better environmental  conditions.

Piezoelectricity

Piezoelectricity, which is also known as the piezoelectric effect, is the  capability of specific matters to generate an AC (alternating current)  voltage when subjected to mechanical stress or vibration. Piezoelectric discs use this piezoelectric effect to create  and use an electrical yield when some kind of mechanical force, pressure,  or vibration is put on. Piezoelectricity is highly linked with renewable energy because “the stimuli for piezoelectric materials can be human walking, wind, rain,  tide, and wave, etc”. This characteristic of piezoelectric discs  and the use of this can be a potential solution to the energy production  problems since it could replace the non-renewable energy sources which  results in a significant amount of greenhouse gas emissions.

The objective of this project

The main objective of this project is to create a piezoelectric-based roof  structure that could be a potential solution to the energy production  problems that many countries around the world are experiencing. The  project will determine the most effective structure of the platform when  generating an electrical output. This project will investigate different  methods of generating electricity using the piezoelectrical effect and will  eventually develop a piezoelectric-based roof that can harvest energy from raindrops (as well as wind).

Idea

From my last year’s ASA project, which was about developing a piezoelectric based platform to harvest energy from footsteps, I realized the great potential of  piezoelectricity to be implemented and used in many different areas, to harvest  renewable energy. Since piezoelectric discs work due to the kinetic energy of  some kind of mechanical pressure applied, I thought it would be a great source of  energy if we go beyond kinetic energy from footsteps, and maybe try focusing on  a greater level. This is how I came up with the idea, to develop a piezoelectric based roof to harvest energy from raindrops. For this research and investigation, I  started by sketching different ideas for the structure, for me to experiment. The  first initial idea was to 3D print individual structures for the piezoelectric discs to  be inserted and connected. However, this structure was not feasible due to its  complexity and unsuitability for a roof structure. Therefore, I decided to start with experimenting shower and water pump structures to investigate the  responsiveness of the piezoelectric discs when energy from raindrops is applied.

Prototype and Experimenting

Before starting to make prototypes and overall structure, it is necessary to make sure everything was waterproof. Silicon and resin were tested but it reduce the sensitivity of piezoelectric disc. Thus, a thin and clear coat spray was used to make the waterproof layer. 

After several trials with wire connections, it was decided to use a series-parallel connection as it provides a more consistent output. Then, a glue gun was used to assemble the piezo and 3D base structure to the foam board, then connected all piezo through soldering. 

Collecting Data

The final product was placed in a rooftop area of the lab to test with actual raindrops. The data was collected for around 10 days using LabVIEW software. The graph shows that the current received was not an outstanding result, considering the time. One interesting fact was that the roof structure was also able to collect energy from wind other than the rain. 

Final shower & roof structure for simulation

After collecting data from actual rain, the results were not satisfactory, so a simulation was conducted. The simulation utilized shower heads and a water pump. This approach made data collection much easier to control and analyze.

Conclusion and Future Applications

Through the various experiments and observations on the prototypes and change of materials, it can be concluded that when developing a roof  structure to harvest energy by using the piezoelectric discs, the connection circuit and the way it attached to the ground matter a lot. The various  prototypes and trial-and-error processes have all proven that developing a new structure for harvesting energy is a difficult and time-consuming  journey. The fact that this roof structure has opened new doors of opportunity for attaining energy from raindrops and wind, I’m looking forward to  investigating further. This investigation has revealed the potential for sustainable energy harvesting for the next generation. This technology and  method of harvesting energy from mechanical stress from raindrops and wind power can be one of the most efficient and globally leading  renewable energy sources in the future. Even though technical challenges and room for improvement are still present, such as energy collection,  storage, and optimization, future investigations will make a better and more innovative solution to this current problem. When this structure,  named ‘Energy Roof’ is developed further in the future, there will be different real-life applications of this product. For example, it can be attached  to the top of the buildings for energy collection. Not only on buildings, but creative implementations, such as on airplanes and spaceships can also  happen, thinking that this structure harvests energy from wind as well.