Solar Panels have decreased dramatically in cost from about $800 in 2008 for a standard 200 Watt Solar Panel to about $300 which means more than a 50% decrease in costs.In these days when the price of electricity and energy is constantly increasing this is an amazing fact and the decreasing cost of Solar Energy has made it the biggest Advantage of using Energy from the Sun.Cheap Chinese Solar Panels can be now be bought as low as $250 in bulk which implies that you can easily buy a Solar Array of 10 Solar Panels for your home at a cost of as low as $2500 .While the initial investment may look high you can look at electricity savings for 25 years as Solar Energy requires NO FUEL and very little maintenance as well.Solar Panels are already ubiquitous in places like Germany and Italy which have strong government support programs called Feed in Tariffs.With prices of energy increasing and Global Warming,its a matter of time when Solar Panels become as common as Lights in your home and offices.Solar Panels Installation is normally done by a Solar Integrator or Installer who decides on which Solar Panels to Buy and Designs the Systems.But as an owner of a Solar Panel System you must have a good idea otherwise you might get cheated upon.
Solar Panel Sizing
Solar Panels come in a variety of shapes and sizes.They are also made up of different materials like for example while most panels are made from silicon (the same material used in electronics),some solar panels are also made up of thin film solar materials like Copper Indium Gallium Selenide or Cadmium Tellerium.Solar Panels can have power of as low as 5 Watts which are needed as solar chargers for batteries for you mobile phones and can be as high as 300 Watts for powering your home.Solar Panels of standard 200-250 Watts are of 5-6 feet in lenght and 3.5 feet in width and can weigh as much as 25 kg.Solar Arrays are made up of a number of Solar Panels which provide the required voltage and power for your electricity requirements.
Solar Panel is made up of Solar Cells which are the basic building blocks of a Solar Panels.A Typical Solar Cell provides around 0.5 Volts and around 60-90 Solar Cells make up a typical solar panel which implies 30-45 Volts .This will provide you around 8-10 Amperes of Electricity for around 200-250 Watts of Power.Note Solar Cells are also of different variety and efficiency.You can read about Solar Panel Efficiency and Solar Cells Efficiency.
Solar Panel Calculator
Calculating how many Solar Panels you need is quite tricky as it depends on the Solar Panels Efficiency,Design of the Solar Array,the place where you live etc.
1) Solar Panels Efficiency – Some Solar Panels are more efficient.For example Solar Panels made by Sunpower and Sanyo are the most efficient which means they require less area.For space constrained homes,they are the best bet but they cost more per watt hour of electricity generated.Click on the heading of this paragraph to understand more about Efficiency.
2) Sun Light or Solar Insolation – This measures the amount of sun light that your solar panel installation recieves.Typical Solar Insolation is around 1000-1500 watt hour per year.This means that if you install 1 watt of solar panels you will get 1-1.5 units of electricity per year.You should first calculate how much electricity you require per year.If you require around 7200 units a year you would need to install a 5 kilowatt or 5000 watts solar array.You can find out the solar insolation you receive from free websites like a) www.nrel.gov/rredc/pvwatt if you live in the USA and b)re.jrc.ec.europa.eu/pvgis/countries/countries-europe.htm if you live in Europe.These websites also give you information about the solar insolation/radiation you live
3) Design of the Solar Array – This is very important in ensuring that you get the most power out of your solar panels.The design of the solar array should always be done by a good solar installer.Note this is a fragmented industry but you can find more about the big solar installers in the USA here.You should ensure basic stuff such that there is no shading of your solar panels,the roof does not leak,the materials used are good.Also having a good solar inverter is important.Nowadays you can get individual solar microinverters for each solar panel as well.Note almost 1-520% of the power generated by your solar panels is wasted in converting from DC to AC.
Solar Panel and Cell Dimensions
A Typical Solar cell of 0.5V and 3 Amperes has a dimension of 60mm x 30mm x 2.8mm (LxWxD) .Solar Cells in Bulk can be bought these days at very cheap prices of 70c/watt.Monocrystalline Solar Cells cost more at 85c/watt while its impossible to buy Thin Film Solar Cells.A Typical Solar cell of 0.5V and 8 Amperes has a dimension of 60mm x 60mm x 2.8mm (LxWxD)
A Solar Panel of 200-250 Watt normally has dimensions 65 inches x 4o inches x 1.80 inches and weight of around 40-50 LBS or 20-25 kgs.Note Solar Panels made from Thin Film have much bigger sizes because of lower efficiency,however their thickness is lower and weight is also a bit lower than similar dimension polysilicon solar panel
Read about Solar Panel Installation Costs here
Solar Panels Costs
Solar Panels cost for the cheapest solar panel manufacturers in around $1.10/watt and they retail for around $2/watt of residential customers.Note for utility large scale buyers of solar panel buyers,the cost is much lower.Solar Panels Costs have trended down quite in the last 3-4 years except in 2010 when they went up as solar panel demand increased by more than 150% .Solar Panel Costs are the biggest component of a Solar System Cost.The costs for Solar Panels are lower for Thin Film Solar Panel for example First Solar Panels are much lower in cost but have lower Solar Panel Efficiency .Solar Panels in general cost between40-60% of the total system costs
Solar Inverter Costs
Solar Inverters cost around 50c/watt for small buyers of solar systems but can cost lower for large kilowatt inverter sizes and for scale buyers.Solar Inverters are a crucial component of a solar system and make up around 10% of the solar system costs.Here is a list of major solar inverter brands
Solar Installation Costs
These are the costs paid to the installers/electricians to connect solar panel systems and the balance of systems (BOS) to the grid or the customer installation.Solar Installations costs can vary between 10-20% of the total costs
Balance of Systems (BOS)
Balance of System components are the solar mounting systems,wires,cabling etc which are needed to mount the solar panels at the right inclination to generate the maximum energy while wire and cabling is needed to connect the solar panels to the inverter and each other.Note BOS can form between 15-20% of the Solar System.Again note the percentage of costs are an indicator and can vary substantially depending on the technology used,region etc.
Most Solar Panel Installations get a government subsidy in most parts of the world and involve a lot of paperwork,regulation,inspection etc.These can vary substantially depending on where the solar panel installation takes place.In USA the red tape involved is quite cumbersome and can form upto 30-40% of the total costs in the worst cases.In Germany which is the world leader in solar energy,the process is very smooth and can be done at 5% of the total system costs.