Team:GreatBay SZ/Description
Intro to IoT
The Internet of Things, or IoT, refers to the network of physical objects capable of gathering and sharing electronic information. With its unprecedented power in connecting physical objects, we can expect IoT to transform a wide range of fields--from medicine to urban planning to consumer data collection.
In the foreseeable 2030, there will be approximately 125 billion IoT devices; every second, 127 devices are being connected to the network[1].
The Critial issue in power supply
As the demand for IoT expands, here comes a fundamental technical problem that requires immediate solution -- How to power billions of IoT devices?
Currently, most IoT devices are supported by lithium and primary batteries, which are limited by lifespan and ecological impact. Chemical batteries, on the other hand, may have the advantage of longer lifespan, but their value for recycling is minimal. It becomes even worse when they need to be replaced in some remote areas where traditional power cannot reach.The following are the main limitations of traditional power-supply solutions:
Environmental Energy is good, but with Higher Requirements.
Other solutions have also been introduced in the industry. One of the latest, and most environmentally friendly solutions would be utilizing environmental energy harvesting technology to collect the subtle energy in the environment; for instance, solar energy obtained from the radiation of the Sun or wind energy derived from turbines.
However, such solutions that harvest energy directly from the surrounding have many constraints on geology factors and climates. In other words, only when IoT devices are positioned in specific locations, can these energy-harvesting technologies be properly applied. In this case, the scope of IoT devices' application may be dramatically limited to areas with, say, ample sunlight or strong wind.
As a result, we need a self-sustained, environmentally-friendly, and highly adaptive solution capable of powering IoT devices.
Why does humidity have great potential?
From the analysis above, we need a self-sustained, environmentally-friendly, and highly adaptive solution capable of powering IoT devices.
Our inspiration came from the discernable humidity in Shenzhen. Throughout the whole year, the humidity of Shenzhen remains above 70%;
What's more, over 70% of the globe has humidity that's higher than 50%[2]. This means that those invisible water molecules floating in the air can be an abundant storage of energy. Still, the question remains: how can humidity be harvested?
Intro to our BIOT
Based on the market demand and our inspiration by humidity in Shenzhen, this year, our team aims to develop a moisture-driven energy harvesting device utilizing biotechnology: BIOT, or Biotechnology Driven Internet of Things. In a nutshell, BIOT is an electric generator that utilizes a thin film of protein nanowires to harvest energy from moisture in the air.
The film is even smaller than a fingernail, but it can stably produce voltage up to 0.35V and current of around 0.5mA. The battery is stable in different conditions with various relative humidity and pH, even in high temperature. Besides, protein nanowires are bio-degradable.
The Core of our BIOT is Electrically-conductive Protein Nanowires (e-PNs). These protein nanowires were originally produced from G. sulfurreducens, and now with our efforts, they can be expressed in E.coli with biotechnology.
What makes e-PN special is that they contain surface Carboxylic groups that provide exchangeable protons as well as internal nanopores that allow the passage of water molecules to create a concentration gradient of ions. These two features combined result in e-PN's ability to generate power from the moisture in the air.
How does BIOT Produce Power?
First, water molecules in the air are ionized when adsorbed on the nanowire surface. The nanowire contains a high-density carboxylic group (-COOH). It is expected that, at higher moisture adsorption, a larger percentage of the carboxylic groups will be ionized (forming H+and -COO ̄ ions)
An ionization gradient will form following the moisture gradient. Since the proton or H+ is mobile (against an immobile -COO ̄ anionic background), it will lead to H+ diffusion from top to bottom.
The diffusion results in a (positive) charge accumulation at the bottom surface and a negative anionic background at the top, creating an electric field (E) that will counterbalance the charge diffusion[3].
What have we done in this summer?
Our project is mainly divided into four sections - BIOT production; Cost reducing; Power Efficiency Improvement and Hardware design. Throughout the whole summer, our team have successfully designed this high-performance electric generator that's driven by moisture in the air and increased its productivity and power efficiency using synthetic biology. We had implemented an integrated human practice to gain feedbacks to our project and developed a business plan to explore the promising business opportunity in the market.
As far as we know, this will be the first time that biotechnology has been applied in the field of IoT. Its advantages in low environmental restrictions, environmentally-friendly materials, stable power generation, long power-harvest duration, low cost, and large-scale applications will promote further global IoT development. Moreover, utilizing biotechnological toolbox, our product has more space for transformation that cannot be touched by traditional methods. We envisioned a Promising, Optimistic and Bright future of BIOT. With BIOT, we can see a grand future where hundreds of billions of IoT devices connected the whole world.
See More About Our Design in Proof-of-Concept page.
References
[1] Data: http://www.cww.net.cn/article?id=469666
[2] Data: https://www.weatherbase.com/weather/countryall.php3
[3] Liu,X., Gao,H., Ward,J.E., Liu,X., Yin,B., Fu,T., Chen,J., Lovley,D.R. and Yao,J. (2020) Power generation from ambient humidity using protein nanowires. Nature, 578, 1–5.