# Architectural Simulation of Hybrid Energy Harvesting: A Design Experiment in Lanzarote Island
## 4 Design Development
### Architectural Design Based on Energy Harvesting Using Micro-Energy Sources  
The definition of micro-energy generation technology, which generates renewable energy from micro-energy sources, is broken down by the amount of electricity generated and the unit of renewable energy generated in microwatts (\(\mu\)W). Furthermore, the meaning of'micro' is not limited to the unit of electricity. It means the size of the electricity production facility: the size of micro-energy harvesters is measured in the unit of millimeters or centimeters [35]. This study selects, among the various micro-energy sources, the tiny vibrations of wind as a source of renewable energy. This is because, firstly, this study aims to develop an architectural design that utilizes piezoelectric materials, which convert minute vibrations into energy [36]. Secondly, the wind power in Lanzarote is sufficient to generate renewable energy. A small-sized wind turbine, a typical energy harvesting facility based on wind, requires a minimum of 3 m\({}^{-1}\cdot\)s\({}^{-1}\) cut-in speed to operate [37]. An analysis of wind resources in the research subject location shows that the average wind speed in 2020 in Lanzarote was 6.5 m\({}^{-1}\cdot\)s\({}^{-1}\), which is sufficient to generate wind-based renewable energy. Moreover, an analysis of the wind direction in the study location shows that the dominant wind direction tends to be north east (NE) and north-northeast (NNE) from January to December (Table 4). There are prior studies related to this study that use wind as a source to produce renewable energy and utilize piezoelectric materials. Studies on the relationship between piezoelectric materials and wind direction focused on optimizing the energy generation efficiency of wind when installing piezoelectric materials. It has been found that to maximize the energy production of piezoelectric materials, it is optimal to install them so that they are perpendicular to the wind direction. The purpose of such an installation plan for piezoelectric materials is to maximize the vibrations generated by wind to the piezoelectric materials, thereby maximizing energy generation [38]. Research has also been carried out on the development of fans that rotate by the wind and on the installation of piezoelectric materials on the blades of these fans [39]. Piezoelectric materials are placed on the blades of the fans. In order to measure the energy generation as a function of wind strength, three piezoelectric materials (PVDF, polyvinylidene fluoride) with a length of 30 mm, a width of 12.5 mm, and a thickness of 0.02 mm are placed on three separate blades. They are made to rotate by a certain level of wind power. As a result, when wind power of 14 m\({}^{-1}\cdot\)s\({}^{-1}\) is applied, the rotation of the fan blade produces a maximum of 2566.4 \(\mu\)W output power. When a higher level of wind power is applied, the output power drops precipitously [40]. Research has been conducted on the creation of piezoelectric flags. Piezoelectric flags are created with the size of piezoelectric materials (LDT4-028 K/L) limited to 60 mm, 75 mm, and 100 mm on each side and with the ratio between the width and the length (W\({}^{-1}\cdot\)L\({}^{-1}\)) set to 2, 1.5, 1, and 0.5. Each piezoelectric flag created is measured for the amount of energy produced at varying wind speeds. As a result, when a piezoelectric material is 60 mm long, \begin{table}
\begin{tabular}{c c c c} \hline \hline
**N.** & **Month** &
\begin{tabular}{c} **Average Wind Speed** \\ **(m\({}^{-1}\cdot\)s\({}^{-1}\cdot\)month\({}^{-1}\))** \\ \end{tabular} & **Dominant Wind Direction** \\ \hline
1 & January & 5.7 & NE \\
2 & February & 6.6 & NE \\
3 & March & 7.2 & NNE \\
4 & April & 5.6 & NNE \\
5 & May & 6.4 & NNE \\
6 & June & 6.4 & NNE \\
7 & July & 8.1 & NNE \\
8 & August & 8.6 & NNE \\
9 & September & 6.0 & NNE \\
10 & October & 6.3 & NE \\
11 & November & 5.3 & NE \\
12 & December & 6.3 & NE \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Annual average wind speed in Lanzarote in 2020 [21].