Transformer oil  :

Transformer oil or insulating oil is an oil that is stable at high temperatures and has excellent electrical insulating properties. It is used in oil-filled wet transformers, some types of high-voltage capacitors, fluorescent lamp ballasts, and some types of high-voltage switches and circuit breakers. Its functions are to insulate, suppress corona discharge and arcing, and to serve as a coolant.

Transformer oil is most often based on mineral oil, but alternative formulations with different engineering or environmental properties are growing in popularity. 

 

Transformer oil's primary functions are to insulate and cool a transformer. It must therefore have high dielectric strength, thermal conductivity, and chemical stability, and must keep these properties when held at high temperatures for extended periods. Typically, they have a flash point greater than 140 °C (284 °F), pour point less than −40 °C (−40 °F), and a dielectric breakdown at greater than 28 kV_RMS. To improve cooling of large power transformers, the oil-filled tank may have external radiators through which the oil circulates by natural convection. Power transformers with capacities of thousands of kilovolt-ampere may also have cooling fans, oil pumps, and even oil-to-water heat exchangers.

Power transformers undergo prolonged drying processes, using electrical self-heating, the application of a vacuum, or both to ensure that the transformer is completely free of water vapor before the insulating oil is introduced. This helps prevent corona formation and subsequent electrical breakdown under load.

Oil filled transformers with a conservator oil reservoir may have a gas detector relay like a Buchholz relay. These safety devices detect the buildup of gas inside the transformer due to corona discharge, overheating, or an internal electric arc. On a slow accumulation of gas, or rapid pressure rise, these devices can trip a protective circuit breaker to remove power from the transformer. Transformers without conservators are usually equipped with sudden pressure relays, which perform a similar function as the Buchholz relay. details

 

Solar Drone @ Possible Services

 

 A drone, is an aircraft without any human pilot, crew, or passengers on board. Drones were originally developed through the twentieth century for military missions too for humans, and by the twenty-first, they had become essential assets to most militaries. As control technologies improved and costs fell, their use expanded to many non-military applications.These include aerial photography, precision agriculture, forest fire monitoring, river monitoring, environmental monitoring, policing and surveillance, infrastructure inspections, smuggling, product deliveries, entertainment, and drone racing.Solar drones are those  which are powered by solar energy.Solar cells or solar  panels are used for development. It can be very small or huge in size depending on it's works.It can be 24 hour on duty drones as it power itself.No fuel costs  but one time  PV installation.

Polycrystalline vs monocrystalline silicon

 

In single-crystal silicon, also known as monocrystalline silicon, the crystalline framework is homogeneous, which can be recognized by an even external colouring. The entire sample is one single, continuous and unbroken crystal as its structure contains no grain boundaries. Large single crystals are rare in nature and can also be difficult to produce in the laboratory (see also recrystallisation). In contrast, in an amorphous structure the order in atomic positions is limited to short range.

Polycrystalline and paracrystalline phases are composed of a number of smaller crystals or crystallites. Polycrystalline silicon (or semi-crystalline silicon, polysilicon, poly-Si, or simply "poly") is a material consisting of multiple small silicon crystals. Polycrystalline cells can be recognized by a visible grain, a "metal flake effect". Semiconductor grade (also solar grade) polycrystalline silicon is converted to single-crystal silicon – meaning that the randomly associated crystallites of silicon in polycrystalline silicon are converted to a large single crystal. Single-crystal silicon is used to manufacture most Si-based microelectronic devices. Polycrystalline silicon can be as much as 99.9999% pure. Ultra-pure poly is used in the semiconductor industry, starting from poly rods that are two to three meters in length. In microelectronic industry (semiconductor industry), poly is used both at the macroscale and microscale (component) level. Single crystals are grown using the Czochralski method, zone melting and Bridgman techniques.

Light-emitting diode

 

A light-emitting diode (LED) is a semiconductor device that emits light when current flows through it. Electrons in the semiconductor recombine with electron holes, releasing energy in the form of photons. The color of the light (corresponding to the energy of the photons) is determined by the energy required for electrons to cross the band gap of the semiconductor.White light is obtained by using multiple semiconductors or a layer of light-emitting phosphor on the semiconductor device.

Appearing as practical electronic components in 1962, the earliest LEDs emitted low-intensity infrared (IR) light. Infrared LEDs are used in remote-control circuits, such as those used with a wide variety of consumer electronics. The first visible-light LEDs were of low intensity and limited to red.

Early LEDs were often used as indicator lamps, replacing small incandescent bulbs, and in seven-segment displays. Later developments produced LEDs available in visible, ultraviolet (UV), and infrared wavelengths, with high, low, or intermediate light output, for instance white LEDs suitable for room and outdoor area lighting. LEDs have also given rise to new types of displays and sensors, while their high switching rates are useful in advanced communications technology with applications as diverse as aviation lighting, fairy lights, automotive headlamps, advertising, general lighting, traffic signals, camera flashes, lighted wallpaper, horticultural grow lights, and medical devices.

LEDs have many advantages over incandescent light sources, including lower power consumption, longer lifetime, improved physical robustness, smaller size, and faster switching. In exchange for these generally favorable attributes, disadvantages of LEDs include electrical limitations to low voltage and generally to DC (not AC) power, inability to provide steady illumination from a pulsing DC or an AC electrical supply source, and lesser maximum operating temperature and storage temperature.

In contrast to LEDs, incandescent lamps can be made to intrinsically run at virtually any supply voltage, can utilize either AC or DC current interchangeably, and will provide steady illumination when powered by AC or pulsing DC even at a frequency as low as 50 Hz. LEDs usually need electronic support components to function, while an incandescent bulb can and usually does operate directly from an unregulated DC or AC power source.

As a transducer of electricity into light, LEDs operate in reverse of photodiodes.

Solar cell

 

A solar cell, or photovoltaic cell, is an electronic device that converts the energy of light directly into electricity by the photovoltaic effect, which is a physical phenomenon. It is a form of photoelectric cell, defined as a device whose electrical characteristics, such as current, voltage, or resistance, vary when exposed to light. Individual solar cell devices are often the electrical building blocks of photovoltaic modules, known colloquially as solar panels. The common single-junction silicon solar cell can produce a maximum open-circuit voltage of approximately 0.5 to 0.6 volts.

Solar cells are described as photovoltaic, regardless of whether the source is sunlight or artificial light. In addition to producing energy, they can be used as a photodetector (for example infrared detectors), detecting light or other electromagnetic radiation near the visible range, or measuring light intensity.

The operation of a photovoltaic (PV) cell requires three basic attributes: The absorption of light, generating excitons (bound electron-hole pairs), unbound electron-hole pairs (via excitons), or plasmons.
The separation of charge carriers of opposite types.
The separate extraction of those carriers to an external circuit.

In contrast, a solar thermal collector supplies heat by absorbing sunlight, for the purpose of either direct heating or indirect electrical power generation from heat. A "photoelectrolytic cell" (photoelectrochemical cell), on the other hand, refers either to a type of photovoltaic cell (like that developed by Edmond Becquerel and modern dye-sensitized solar cells), or to a device that splits water directly into hydrogen and oxygen using only solar illumination.

Photovoltaic cells and solar collectors are the two means of producing solar power. 

 

 

 

 

Image: Solar cell symbol

Renogy Flexible Solar Panel 50 Watt 12 Volt Monocrystalline

 

• Extremely Flexible] This flexible panel is capable of meeting a wide range of applications where standard panels can be inconvenient to mount, such as on the curved roof of an airstream
• [Ultra Lightweigh] Thanks to advanced polymer materials, this product weighs 70% less than conventional solar panels, making transportation and installation a breeze
• [Super Thin Lamination] Hardly noticeable, the Renogy 50W Lightweight Panel laid flat is only a tenth of an inch tall. Approximately 95% thinner than its rigid counterpart, this panel is ideal for a stealthy solar setup
• [Highly Durable] Rigorously tested, the 50W panel Was designed to withstand extreme wind of up to 2400 PA and snow loads of up to 5400 Pa
• [Potential Uses] The Renogy 50 Watt Flexible Monocrystalline Panel can be primarily used on off-grid applications that include marine, rooftop, RV, boats and any curvy surfaces 

 

 Traditional solar panels are rigid and often enclosed in tempered glass. The Renogy 50W Flexible Solar Panel is anything but traditional. Perfect for marine use or placement on top of a van or vehicle, the Renogy 50W Lightweight Solar Panel is thin and capable of flexing up to 248 degrees. At 2.87 pounds, this flexible solar panel weighs only a quarter of its traditional 50W counterpart. Highly flexible, this lightweight panel can easily be installed on curved surfaces. This panel can also be used for other various applications, including providing power on a boat or teardrop trailer. 

Link to Buy : Amazon