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Robotic future. Solar Drones

19.02.2018 — 0

Dron is a simplified name for unmanned aerial vehicles, also known as UAVs. Flying and floating small size devices are created for a variety of purposes: from aerial photographs to goods delivery. The world-famous company Amazon has patented its own system for the delivery of goods with the help of drones. At the moment, the service is being tested in the UK, Israel, and Canada. As the developers stated, the drones will be able not only to take the parcel to the customer’s house but also to hand it in any place — even if the buyer is moving.

Picture by maddchadd

In addition, that drones perfectly help improve everyday life, some robots are created to take care of future and environment.

*Solar DAO — a tokenized fund designed for everyone to easily participate in PV solar plants construction across the globe. SDAO tokens on: *YoBit

Water cleaning

Last year, a group of inventors presented the first prototype of a robotic cleaning water device — SeaVax. The device is created in the form of a boat with a storage container and all kinds of sensors. A drone is powered by solar energy — the modules are installed on the boat’s roof. It is designed to collect plastic waste in the UK waters, and the government of India is already interested in such invention. Due to the sensors, the cleaner does not confuse plastic with live water inhabitants and does not harm the environment. According to the developers, the boat is able to catch more than****20 thousand tons of harmful plastic waste per year.

SeaVax

This drone is not the only one existing on the market. The company RanMarine has created its own robot for water purification around Rotterdam — Waste Shark. Dron operates in an autonomous mode, charging from the built-in solar panels. Such a device is capable of catching up to 500 kg of garbage at one session.

Internet access

The world’s largest corporations are testing new ways of transferring data using automated drones. Google created its own program called SkyBender to distribute the new high-speed 5G Internet. The company plans to launch its own drones in locations with connection problems. Test launches of transceivers, operating on solar energy with their own modules are conducted in New Mexico. At the moment, Google is still working on improving the performance of drones, since the signal attenuation problem is still relevant. Nevertheless, the company has all chances to succeed in this project soon.

The head of Facebook, Mark Zuckerberg, plans to provide a high-speed connection for more than 4 billion people. The company has already conducted several successful test launches of its own Aquila drones, working on solar panels. According to the creator, the drone will be adapted for flights not only for long distances but also for a very long work time — about 90 days in the air.

Prospects for Solar Drones

Alta Devices has developed special thin solar modules to cover drones. New technology allows creating very thin and highly efficient solar modules. According to the developers, this material is ideal for unmanned aerial vehicles. Flexible panels can be used on any surface, without interfering with aerodynamics and without increasing the drone’s weight.
Also: Audi plans to launch its own electric cars using the thin solar panels technology from Alta Devices.

Useful solar drones

Let’s take a look at a few solar powered UAVs used in various industries:

  1. “Owl”. The Foundation for Advanced Studies, together with Tiber, successfully tested a new drone designed for operation in the northern regions. The solar drone is designed for monitoring the area, as well as for data transmission, which will be much cheaper than conventional satellites.
  2. A special drone for the pipeline service was created in China. Monitoring networks usually takes a long time, as it is done manually by specialists. The development team from China demonstrated its new development — a lightweight unmanned aerial vehicle on solar modules. This drone can be successfully used due to a long working time — from one month of continuous flight.
  3. V3 for cartography. Recently, the world knew about the ultra-light drone created for 3D design. Tsubasa V3 is a 250-gram drone equipped with solar panels for charging. The robot can be used for other purposes — for checking damage from natural disasters, inspecting buildings, monitoring environmental objects.

Pic credit: thenextweb

  1. “Live” drone. Scientists from HHMI have developed a unique small drone based on a real dragonfly. To do this, experts have derived genetically modified dragonflies, which can be controlled by light signals. The modified dragonfly is equipped with a special transmitter and tiny solar modules, through which the insect gets commands by light flashes. 
    **The winged cyborg can be used on bee apiary **or as a **new tracking method **:).

Solar DAO — a tokenized fund designed for everyone to easily participate in PV solar plants construction across the globe. SDAO tokens on: YoBit.

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PV solar cells production

17.08.2017 — 0

The Production of the Solar Cells

PV solar cells combined into in solar module (panel)

After the silicon crystal had been grown and cut into wafers, the latter are used in the production of photo transformers — the solar cells. This process goes in several stages. This articles explains the conventional sequence of solar cells production process that is widely applied in contemporary solar industry.

The stages are as follows:

  1. Chemical milling of the surface (acid- or alkali-based)
  2. Diffusion — the creation of a working p-n-junction
  3. Texturing
  4. The construction of the antireflection layer
  5. Forming of an electric current collector (or contact lattice)
  6. Burning-in of the electric current collector (or contact lattice)
  7. Tests using the sun imitation lamp

Some of the contemporary production lines may have additional processes, but in general the technology involves the processes described above. Let’s begin with the first two stages.

Chemical etching

The surface of the starting wafer can have a lot of defects, microcracks and contaminations that emerged during the crystal cutting process. The presence of such defects increases the rate of recombination (endings) of the carriers and decreases the efficiency of photoelements. Thus, chemical milling is naturally the first step. In practice, it depends on the crystal type and the specifics of the production line, and can be done in both acid or alkali mortars.

Diffusion

After the wafer surface has been chemically cleaned, it is necessary to create a p-n-transition. Generally, diffusion is the net movement of molecules or atoms from a region of high concentration (or high chemical potential) to a region of low concentration (or low chemical potential). In the process of diffusion, the admixtures move from the region of high concentration to the region of low concentration under the influence of high temperature. In this process the atoms of electrically active admixtures diffuse into the crystal lattice of silicon, creating the areas with p- (positive) or n-(negative) electrical conductivity. In the local diffusion defence masks are used that are made of dielectric (non-conducting) films.

This process is widely used to create the p-n-junction which serves as a kind of energetic barrier for the electric current carriers and lets them pass through in only one direction. Thus, the sunbeams that reach the surface of the solar cell release the carriers with different charge within the semiconductor material — holes (p) and electrons (n). This is the foundation of the electrical energy generation within the solar cells. The p-n junction functions as a “separator” that directs the movement of different types of carriers into different directions. Thus, chaotically moving carriers of charge (charged particles) reach different sides of the barrier and then are transmitted into the external circuit to create voltage.

Usually, the diffusion is carried out in a quartz tube placed into a special diffusion furnace with atmospheric pressure, under the temperature around 800–900 C. The admixtures used in the diffusion process include solid, liquid, gaseous, solid planar and surface sources. As a rule, the use of these sources of admixtures implies the application of the gas system. By regulating the timing, that is, for how long the silicon wafers are in the reactor, as well as the regulation of the temperature and the gas flows inside, professionals learned how to get the p-n-junction with the properties needed.

For example, in the process of phosphorus diffusion, a liquid substance is used as the source — namely, phosphorus oxychloride (POCI3); in the diffusion boron this role is played by boron nitride (BN). The diffusion process itself consist in putting the silicon wafer together with some admixture source into the quartz cassette, then moving it into the reaction area of the diffusion furnace for some time under fixed temperature. The gaseous oxide that evolves thereby diffuses to the silicon surface and interacts with it, which results into the formation of the glass layer from which the diffusion goes deeper into the semiconductor. Thus, on the surface of the silicon wafer emerges a layer with electrical n-conductivity which then takes part in the formation of the p-n-junction.

Nowadays the technique of ion bombardment is becoming increasingly popular. The advantages of this mechanism include a high degree of purity, as well as the possibility to control the quantity of the embedded atoms and the depth of their embeddedness.

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How PV cell work