Solar electric power system basics home power magazine electricity related words


A PV array is the energy collector—the solar “generator” and does so via the photovoltaic effect. electricity quiz and answers Discovered in 1839 by French physicist Alexandre-Edmund Becquerel, the photovoltaic effect describes the way in which PV cells create electricity from the energy residing in photons of sunlight. When sunlight hits a PV cell, the cell absorbs some of the photons and the photons’ energy is transferred to an electron in the semiconductor material. With the energy from the photon, the electron can escape its usual position in the semiconductor atom to become part of the current in an electrical circuit.

Most PV cells fall into one of two basic categories: crystalline silicon or thin-film. Crystalline silicon modules can be fashioned from either monocrystalline, multicrystalline, or ribbon silicon. Thin-film is a term encompassing a range of different technologies, including amorphous silicon, and a host of variations using other semiconductors like cadmium telluride or CIGS (copper indium gallium diselenide). Thin-film technology generates a lot of the current R&D chatter, but crystalline modules currently capture more than 80% of the marketplace.

PV-DIRECT SYSTEMS: These are the simplest of solar-electric systems, with the fewest components (basically the PV array and the load). gas stations in texas Because they don’t have batteries and are not hooked up to the utility, they only power the loads when the sun is shining. This means that they are only appropriate for a few select applications, notably water pumping and ventilation—when the sun shines, the fan or pump runs.

OFF-GRID SYSTEMS: Although they are most common in remote locations without utility service, off-grid solar-electric systems can work anywhere. These systems operate independently from the grid to provide all of a household’s electricity. gas tracker These systems require a battery bank to store the solar electricity for use during nighttime or cloudy weather, a charge controller to protect the battery bank from overcharge, an inverter to convert the DC PV array power to AC for use with AC household appliances, and all the required disconnects, monitoring, and associated electrical safety gear.

BATTERYLESS GRID-TIED SYSTEMS: These most common PV systems are also known as on-grid, grid-tied, utility-interactive, grid-intertied, or grid-direct. gas density calculator They generate solar electricity and route it to the loads and to the electric utility grid, offsetting a home’s or business’s electricity usage. System components are simply comprised of the PV array, inverter(s), and required electrical safety gear (i.e., fuses/breakers/disconnects/monitoring). Living with a grid-connected solar-electric system is no different than living with utility electricity, except that some or all of the electricity you use comes from the sun. (The drawback of these batteryless systems is that they provide no outage protection—when the utility grid fails, these systems cannot operate.)

You are going to have problems with mini-inverters in the blazing summer months in Arizona, especially if the structure has heating issues during the peak hours of the day. gas used in ww1 Many factors actually go to play there including direction of azimuth of your roof, angle of the roof, and the capabilities of cooling any system on top of your roof. In addition you require more system equipment if you decide to get a battery backup system. In contrast, a natural gas generator for inclement weather backup might be more cost effective and offers the same safety AC cut-off that is required of a battery backup system without the need for controller and charger control systems or conversion losses from AC to DC and then back again. gas 76 station It simply makes permitting and design much more complicated. Try looking for the best practices of both Solar PV and of generator backups before you make up your mind. Cost is going to be a major factor in that decision. gas giants You’re just better off with a conventional inverter system unless the load is high and you are running a commercial system. Even then, unless you are using specific Solar PV such as Thin Film, it is more cost effective to use a single inverter and it produces a cleaner energy signal. But always compare. Knowing what you want to do with your back up is also important in determining a practical backup.

Thanks for posting! In the case of a batteryless PV system, generally speaking the output of our grid-tied inverter will connect with our main service panel by "back feeding" a circuit breaker in that panel. After that point either the loads in the home will use all the power as it is generated by the PV system, if the household power requirements meet or exceed the PV system production. gas oil ratio units If the PV production exceeds what is required by the household loads then the excess power is then pushed onto the grid. And conversely if the Pv system isn’t producing enough power to cover the requirements of the household loads, then the grid will supply the additional required power.

Now that is the common way to interconnect the PV system with the grid…however some incentive programs may require a buy-all-sell-all configuration (perhaps that is the case with SCE?) where the PV system simply "sells" all power to the grid (via a supply side connection and separate meter) and the house "buys" all power from the grid. And this is common for Feed-in-Tariff programs.