Photovoltaic
Photovoltaic (PV) is the field of technology and research related to the application of solar cells for energy by converting sunlight directly into electricity. Due to the growing demand for clean sources of energy, the manufacture of solar cells and photovoltaic arrays has expanded dramatically in recent years. Photovoltaic systems require high quality silicon. Although worldwide there are only very few manufacturers of the silicon wafers required (thin wafers of almost pure silicon), production capacities are increasing all the time. Silicon has a decisive social advantage in that unlike oil, sand is available in limitless quantities everywhere, thereby avoiding damage to or conflicts with the environment. Silicon is the second most abundant element on Earth after oxygen. Sand, quartz or semi-precious stones like amethyst or opals consist essentially of silicon.
The components of a PV system.
- Photovoltaic Cell - Thin squares, discs, or films of semiconductor material that generate voltage and current when exposed to sunlight.
- Module - Photovoltaic cells wired together and laminated between a clear superstrate (glazing) and encapsulating substrate.
- Array - One or more modules with mounting hardware and wired together at a specific voltage.
- Charge Controller - Power conditioning equipment to regulate battery voltage.
- Battery Storage - A medium that stores direct current (DC) electrical energy.
- Inverter - An electrical device that changes direct current to alternating current (AC) to operate loads that require alternating current.
- DC Loads - Appliances, motors and equipment powered by direct current.
- AC Loads - Appliances, motors and equipment powered by alternating current.
How do the PV panels work?
A solar panel (module) is made up a number of solar cells. Solar cells are generally made from thin wafers of silicon, the second most abundant substance on earth, the same substance that makes up sand. To make the wafers, the silicon is heated to extreme temperatures, and chemicals, usually boron and phosphorous, are added. The addition of these chemicals makes the silicon atoms unstable (their electrons less tightly held). When photons of sunlight hit a solar panel, some are absorbed into the solar cells, where their energy knocks loose some of the modified silicon's electrons. These loose electrons are forced by electric fields in the PV panel to flow along wires that have been placed within the cells. This flow of electrons through the wires is electricity, and will provide power for whatever load we attach (a calculator, a light bulb, a satellite, etc.) Because solar cells are modular, a system's size can be increased (or decreased) over time, according to need.
Photovoltaic systems with or without batteries.
Introducing batteries to a PV system allows electricity to be stored and can then be used to provide power after the sun goes down. The simplest and least expensive PV systems are designed for day use only. These systems consist of modules wired directly to a DC appliance, with no storage device. When the sun shines on the modules, the electricity generated is used directly by the appliance. Higher insolation (sunshine) levels result in increased power output and greater load capacity. And when the sun stops shining, your appliance stops working. These simple systems are an appropriate, cost-effective option for loads operated only during the daytime. Examples of day use systems include: • Remote water pumping with a storage tank. • Operation of fans, blowers, or circulators to distribute thermal energy during the day for solar water heating systems or ventilation systems. • Stand-alone, solar-powered appliances such as calculators and toys. It is also possible, in a utility grid interconnected system (see below), to do without batteries, as such a system is essentially using the grid as its storage device.
What is a utility grid interconnected system?
Utility-connected systems, also called "grid-connected" or "grid-tied" systems, are for homes or commercial buildings that are connected to an electric utility. They are designed to provide a modest part to all of the building's total electricity needs. Advances in solar power electronics make it relatively easy to connect a solar electric system to the utility. Energy generated by such a system is first used within the home, and surplus power is "pushed" onto the utility's wires. When this happens, the utility may buy electricity from the homeowner. A draw-back of connecting your PV system to the grid (and using the grid as "storage") is that when your area suffers a power outage, your PV system automatically shuts off. (This is done intentionally, in order to protect people working on the lines from live electricity.) To avoid this problem, many people introduce batteries to their grid-tied system, which provide power in the event of a utility power outage.
The number of PV panels needed for a home.
This depends on how much electricity you use in your home, and where your house is located. The average household uses 600 Kilowatt-hours of electricity per month. However, an energy efficient home may use only half that. In a sunny climate, a 2 kilowatt PV system can produce 300 kilowatt-hours of electricity per month. Therefore, the first step in planning a solar system is reducing electricity consumption. It is always more cost-effective to invest in energy efficiency than to install a larger PV system. Planning, mindfulness and some initial investment can result in a dramatic reduction in electricity use, without sacrificing the comforts to which we've become accustomed.
How can we conserve energy?
A household can save electricity a number of ways, including: purchasing energy efficient appliances and fixtures (e.g. compact fluorescent lights); using solar thermal energy (e.g. drying clothes in the sun, using a solar hot water system); investing in propane or natural gas-powered major appliances (such as refrigerators, stoves, and clothes dryers); and cutting back on appliance use (e.g. turning off lights, abandoning the electric can opener).
OUR GUARANTEE
Our complete range allows installation of conventional grid-connected systems, grid-connected backup systems and self-sufficient systems. We offer maximum quality, simple installation and excellent value for money.
• 10 years quarantine of 92% of full performance
25 years guarantee for 82% of full performance
• Energy production 365 days of the year
• Reliable and longevity
• Silent mode
• Automatic function
• No emissions
• Able to place on any type building, sloping/flat rooves, land etc
• Possibilities of extending the system in the future.