Various forms of Solar Panels

Sep 9, 2017   //   by admin   //   Knowledge Base  //  No Comments

Solar Energy is the second most widely used renewable form of energy after Hydropower. It is predicted that solar energy will show a steady increase and will provide a third of the total energy by 2060. A solar panel is a packaged or connected assembly of photovoltaic cells. It is further connected to make a large photo voltaic system to generate electricity for residential and commercial purposes. Solar panels are most efficient when they are facing sun in an angle close to the perpendicular. Due to the rotation of earth this angle is variant throughout the year. We need to adjust the angles of mounts four times throughout the year.

  • Feb 5th – same angle as your latitude.
  • May 5th – same angle as your latitude minus 15 degrees. At noon the panel will be almost horizontal to the ground.
  • August 5th – Set at the same angle as your latitude.
  • November 5th – Set at the angle of latitude plus 15 degrees. This tilts your panels towards the sun as it travels low in the southern sky during the winter season.

There are four forms of solar panels:-

  • Trackers
  • Fixed racks
  • Ground- mounted
  • Rooftop solar panels
  • Building Integrated Photovoltaic(BIPV)

Trackers: –

These behave like sunflowers in nature. A solar tracker is a device that orients various payloads toward the sun. They sense the direction of the Sun and tilt the panels as needed for maximum exposure to the light. There are two types of application of photo-voltaic trackers:-

  • Flat-panel photovoltaic – trackers are used to minimize the angle of incidence between the incoming light and a photovoltaic panel.
  • Concentrated photovoltaic – trackers are used to enable the optical components in the CPV and CSP systems.

Solar energy collectors or payloads can be mounted in two different ways either Fixed or Moving. Fixed collectors have rotating mirrors instead of solar panels, while In Moving collectors use single or dual axis for rotation.

Fixed Racks: –

Fixed racks hold panels stationary as the sun moves across the sky. The panels move with the earth’s orbit to capture the greatest amount of solar energy possible. The fixed rack sets the angle at which the panel is held. Tilt angles equivalent to an installation’s latitude are common. It can be fixed on ground, pole or roof.

Ground-mounted: –

It is the most easy way of mounting. These use racks or frames to hold solar panels attached to ground based mounting supports like cement slabs. These have optimal efficiency and solar power tracking abilities. These are easy to maintain and clean. The ground- mounting based support includes:-

  • Pole mounts – These can be directly fixed in ground or embedded with a help of concrete.
  • Foundation mounts – These are fixed with help of a slab or rack for e.g. cement slab.
  • Ballasted footing mounts – These have concrete slabs and steel bases to hold system in position and doesn’t need penetrations.

Roof mounted :-

These are the most popular form of mounting and have best application where there is less space available especially in metro cities. In this type of mounting system solar panel is held via rack or a frame and is integrated into the roof of a building with a few inches gap and parallel to the surface of the roof. These includes following types of supports: –

  • Pole mounts: These are directly attached to roof via a pole.
  • Ballasted mounts: These are connected via concrete or steel bases. These allows to the rearrangement of solar panel systems with no adverse effect on the roof structure.

Building Integrated Photovoltaic (BIPV):

Building-integrated photovoltaic (BIPV) are photovoltaic materials that are used to replace conventional building materials while the construction of buildings. These are catching much popularity as it is cost efficient and can be integrated at the time of construction only. They are available in several forms like flat roofs, pitched roofs, facade and glazing.

Among all flat roofs is most widely used technology which uses thin film modules integrated in to flexible polymer membrane. Pitched roofs have modules shaped like roof tiles and increase the roof life by protecting insulating membrane and degradation by water. Facades can be installed on existing buildings and giving old buildings a new look to the building. And Glazing use semi-transparent PV materials at the time of construction only.

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