Friday, 23 May 2014

How to install solar panel at roof top and stay off the grid life chapter-1

How to install solar panel at home's roof top and save electricity and stay of the grid life forever-chapter-1




What are solar panels?,  what are the types of solar panel?,  How efficient are they?

 By: Alok kumar





 



From now we are going to start a solar panel project which will guide the solar energy enthusiasts to install solar pannel at home and stay grid free life.

Before starting a step by step tutorial on How to install solar panel at home's roof top to stay off the grid life, we should know certain basic things first. These are:

  • we should know that what actually a solar panel is?
  • what are the types of solar pannels?
  • How efficient are they?

What are solar panels?

Solar panels are devices that convert the light into electricity (only DC). They are called "solar" panels because most of the time, the most powerful source of light available is the Sun, called Sol by astronomers. Some scientists call them photovoltaics which means, basically, "light-electricity."

Solar panel wings installed on satellite in deep space


A solar panel is a collection of small solar cells. Lots of small solar cells spread over a large area can work together to provide enough power to be useful like an power house. Here the more light hits a cell, the more electricity it produces, so spacecraft are usually designed with solar panels that can always be pointed at the Sun even as the rest of the body of the spacecraft moves around, much as a tank turret can be aimed independently of where the tank is going.

special purpose DS1's solar cells are even more efficient than regular solar panels made for satellites because they use solar concentrators.

Whar are the types of solar panels?


There are two basic types of solar panels, crystalline and thin-film. The characteristics of these are similar but the method of manufacturing is very different for these two is very different.

     Crystalline type:

crystalline module is made from a number of discrete cells, usually 36 for a 12 Volt module. These cells need to be assembled and soldered together by hand, which goes some way to explaining the relatively high price of crystalline modules. Each cell is made from a wafer, composed either of a single crystal (monocrystalline) or many crystals (polycrystalline) of a semiconductor material, generally silicon. The monocrystalline cells are of slightly higher efficiency, but for all practical purposes they can be regarded as the same. Polycrystalline solar modules can be identified by the crystalline appearance of the polycrystalline solar cells.

     Thin Film or Amorphous type:


Thin film or “amorphous” solar modules are made by a different process. A thin film of semiconductor material is deposited on a substrate, usually glass. This substrate forms the body of the solar module. A laser is then used to score the material in order to produce individual cells, which produces the characteristic striped appearance. This method uses less of the semiconductor material and is easier to automate and can be mass produced easily. The solar modules thus produced are therefore are of lower cost. However, commercially available thin film solar modules or amorphous have significantly lower efficiency than crystalline modules. This limits their applications where there is no size restriction on the solar array and adds to the cost of installation.


How efficient are solar panels?

DS1's solar panels convert 22% of their available solar or sun energy into electrical energy or power. This may not sound very good, but it is much better than most solar panels. Most solar panels are fairly inefficient. Less than 14% of the energy that reaches on them will be converted to electricity. DS1's panels are the highly efficient panels available.


Characterstics or operation of 12v 36 cell solar panel:

Here figure shows the relationship between voltage and current for an 12 Volt 36 cell solar module, the most common configuration. The two curves represent different isolation levels.

The current that a photovoltaic module will deliver into a short circuit is known as the short-circuit current or Isc. This is proportional to the insolation, so the more the sun shines the greater the current.

The open circuit voltage or Voc is determined by the number of cells in series, and is not significantly affected by the insolation. You can see that over the working voltage of a 12 Volt load such as a battery the current is nearly constant for a given value of insolation.

In this tutorial we have got a basic knowledge of what is solar panel, what are the types available in the market, which one is cheap and which one have high efficiency, here we have also seen the power characterstics of the 12v 36 cell solar cell configuration.

Now we need to move forward In the next tutorial or post i am going to explain how to choose the solar pannel in quantity as well as quality, and what power rating should be selected to live off the grid life at minimum cost. The next tutorial will assume the total time between sun rise and sun set is 7:30 hours.

Thank you for reading. Stay tuned by just following me on google+. and for any query please ask that in comment section.  







How to install solar panel at roof top and stay off the grid life chapter-2

How to select the type, Quality and quantity of Solar Panel for living a Grid free life. What are the total daily Wattage requirement for average household.


By: Alok kumar

How to select the best solar panel for home to enjoy grid free life, is the most popular question asked by the guys all around the world. To understand how to choose the solar panel array one should be familiar with certain electrical terminology which are ( if you simply know this basic thongs skip this paragraph):


  • Voltage
  • Amperage
  • wattage 

Voltage: The potential difference between two points. Is measured in Volts (V) and has the symbol                   ‘V’.

Current: The flow of electrons in a circuit. Is measured in Amps (A)and has the symbol ‘I’.

Resistance: A material’s opposition to an electrical current. Is measured in Ohms (Ω) and has the                          symbol ‘R’.

Power: The rate of doing work. Is measured in Watts and has thesymbol ‘P’.

Energy: The capacity for work, the product of power and time. Has the symbol ‘E’. The basic unit of              energy is the Joule, but electrical energy is normally expressed in Watt hours (Wh) or kilo                    Watt hours (kWh). One kWh is 1000 Wh.

The relationship between these units is:

                  P = VI
                  or V = P/I or I = P/V

                  V = IR
                  or I = V/R or V = I/R

                 P = I2R



Power equals voltage multiplied by current. This can also be expressed in the other two forms shown.

Voltage equals current multiplied by resistance. Again there are two other forms shown. This is known as ‘Ohm’s law’.

Power equals current squared multiplied by resistance.

Now we are prepared to start the above discussion that How to choose the optimum solar panel for home.

How to choose an optimum solar panel for homes.


We have to consider different points when choosing optimum solar panel array. These points are:
  • How much wattage we need daily.
  • Space we have and space required by solar panel for such daily power requirement.
  • How to calculate the actual daily power needed.