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How do I choose the best solar PV system for me?

Choose the best solar PV system for your home If you go back twenty years, then choosing the best solar PV system would not have been difficult – because you wouldn't have had many options! Domestic solar panel manufacturers were few and far between, and companies willing to install a solar PV system for you would have been even harder to find.

Thankfully, the world has begun to wake up to the potential of solar as a clean, renewable source of energy, and both solar panel manufacturers and installers are much easier to find. Both of these factors have meant that the price of panels and installation has fallen sharply, particularly in the last five years or so, as the market has become much more competitive. Previously, German panels were seen as the PV panel of choice, but more and more Asian companies (particularly Chinese companies) are starting to produce panels that are just as efficient as their German counterparts.

When it comes to choosing the best solar PV system for you, there are three things you need to consider: how much energy you will be using, how much appropriate roof space you have, and how far your budget can stretch.

Factoring it all together

For a family of two adults and two children, if you want to generate enough power so you are in effect, “off the grid”, you are going to need a system worth between 5kWh and 10kWh. For a 5kWh system you're going to be looking at spending between $14,000 and $20,000 – a 10kWh system will put you closer to $30,000. As for the roof-space, for a 5kWh system you are looking at room for 10 panels, and of course 20 panels for a 10kWh system.

If this all sounds a bit too much for you, then don't worry as you can still install a 4kWh system for between $10,000 and $12,000, which will generate between half and two-thirds of the electricity your family uses on a daily basis. You will not be “off the grid” but you will at least be reducing your utilities bill by partially powering your home with solar power.

Why do quotes differ so much?

If you manage to arrange quotes from two different solar energy system providers, then you may be surprised that the figures they quote for the supply and installation of a solar PV system differ significantly.

The reason for this is likely to be the standard of the PV panels that they use – the more expensive the installation, the more efficient the panels. However, you need to make sure this is the case, and that the company with the higher price tag are simply not just trying to overcharge you. Ask each installer how much energy their system is expected to produce in the first year, and then divide the total cost that you have been quoted by the amount of energy produced. Whichever system gives the greater amount, then that is the system you should be going for, as – if the promises made by the installer are correct – that will provide you with the best value.

By making a careful choice, you'll end up with the most effective solar PV system for you, and you'll soon be benefiting from cleaner, greener solar energy.

The State of Solar Power in California Today

Photovoltaic Field in California If there's one thing that California has an abundance of, its sunshine. It could easily have laid claim to the state motto 'The Sunshine State' if Florida hadn't gotten there first. Instead, Californians have to be content with 'The Golden State', and the 3,000 hours or so of sunshine per year that the people of San Francisco, Los Angeles and San Diego have to put up with.

Naturally, there's potentially a massive amount of energy that could be tapped within those 3,000 annual hours of sunshine, and moves have been made in California to do just that. In a joint venture between the California Energy Commission and the California Public Utilities Commission, a campaign named 'Go Solar California!' has been instigated. The campaign has been set up to educate the people of California on the benefits of using solar power, as well as creating a central resource of information for any Californians who want to consider making solar power part of their lives, but don't really know where to begin.

The Go Solar California! Campaign has set itself two goals:

• To encourage Californians to install at least 3,000 megawatts of solar energy systems in their homes and businesses by the start of 2017.

• To install 585 millions therms of gas-displacing solar water heating systems by the start of 2018.

As part of this campaign, Go Solar California! has created the California Solar Initiative, which is a solar rebate program for investor-owned utilities customers, namely the customers of Pacific Gas and Electric, Southern California Edison and San Diego Gas & Electric. The CSI program funds solar energy installations on existing homes, and existing or new agricultural, commercial, governmental and not-for-profit business premises. People who install and use solar energy within their homes will qualify to receive money-saving rebates.

California has something of a trail-blazing reputation when it comes to solar power. In 1978, the US Congress passed the Energy Tax Act which encouraged home-owners to invest in solar and wind energy technologies, as a reaction to the energy crises of the 1970s. In 1979 ARCO Solar commenced construction of the world's large photovoltaic (the means of generating power from sunlight) manufacturing plant in Camarillo, California, and in 1981 opened Solar One in Daggett California, the world's first large-scale thermal solar power plant. As of 2014, no less than four major solar power plants were under construction within the state of California:

• The 550 MW Desert Sunlight Solar Farm in Riverside County

• The 550MW Topaz Solar Farm in San Luis Obispo County

• The 500MW Blythe Solar Power Project, also in Riverside County

• The 250MW California Valley Solar Roach in the Carrizo Plain

With global warming now being an undeniable factor in everyone's lives, and with traditional fuel sources such as fossil fuels rapidly diminishing, the time has really come when everyone ought to take responsibility for our planet's future, so it remains habitable for our future generations. Campaigns such as Go Solar California! and incentives such as the California Solar Initiative are one real leap forward in hoping to encourage as many people as possible to do just that.

So what are the components of a solar power system ?

Solar power components When you see solar panels on someone's roof, you know that that person has invested in a solar power system, but have you ever stopped to think what extra components are needed for a system to work? Here is a complete guide to all the elements you need for a solar power system.

The Panels

PV (photovoltaic) panels are the most common type of panel, especially for residential installations. They are made from three layers:

* The N-Layer – silicon that is mixed with phosphorus

* The P/N Junction – pure silicon

* The P-Layer – silicon that is mixed with boron

When sunlight strikes the N-Layer, it knocks electrons loose. These electrons pass through the P/N junction (which is a one-way junction) into the P-Layer. This creates an electrical field that then drives the electrons that have been “knocked off” from the silicon, creating an electric current.

The Inverter

If you know your physics, then you will know that the electric current that is generated in this way is direct current (DC), which is like the electricity stored in batteries. However, mains electricity is alternating current (AC) where the flow of electricity changes direction 50 times a second. To make the electricity supplied by solar power suitable for use in domestic homes, a device is needed that converts DC current to AC current, and this device is called an inverter.

An inverter works in a very simple way, using a series of switches which are known as “solid state switches” that “flips” the DC current backwards and forwards 50 times a second, to create the AC current.

The Battery

Not all solar power systems have a battery, but some systems that produce more electricity than is needed for the building they are powering have a battery connected to store this excess energy. The stored energy can then be used when the solar panels are not providing enough energy, such as dark and rainy days.

The Distributor

The distributor is the device that distributes the AC power created by the inverter to the grid, and sometimes to both the home in which the solar power system has been installed and the grid. The output from the inverter is fed to a dedicated breaker in your house's electric panel, and then through to your home. If you are creating more power then you are using, then some of the power flows backwards and into the grid, and you receive a credit from your utilities company. If your system is not supplying enough energy for your home, then the shortfall is made up as usual by your utilities company.

These are the basic components of any solar energy system and as you can see, solar power is not a complex energy system – the cells create DC current, the inverter changes it to AC current, and the distributor controls the way in which power is distributed between your home and your utilities supplier.

Now you understand the components that make up a solar energy system, why not consider making the switch to the money-saving, cleaner and more environmentally-friendly source of energy that is solar energy ?

What Are The Differences Between Residential and Commercial Solar Power Systems?

Commercial solar power plant It is not only individuals who are increasingly likely to embrace solar energy these days. More and more commercial enterprises are making the leap to power their buildings with electricity created via the free energy received from the sun. Not only does making the switch save money, but such companies are hoping they will be viewed more favorably if they are seen to be displaying a commitment to more environmentally-friendly energy sources.

The question though is, what's the difference between residential and commercial solar power systems?

The most obvious answer is the scope. While a home has only a small number of people using electricity, the amount of people at a commercial premises can easily number into the hundreds. Solar panels for residences are usually smaller, and generate less power. This is because the roof space of residential buildings is less than the roof space of commercial buildings, so while a residential solar panel typically has 72 cells, a commercial solar panel will be about twelve inches wider, and have 96 cells.

Solar energy is a black and white issue

Commercial solar panels are also like the Model T Ford – you can have any color you like, as long as it's white. While most residential homes who go for solar are happy to accept white panels, if you do not want your panels to be so apparent, you can go for black ones instead.

As commercial panels are also likely to be needed to generate more power, they are usually more expensive per panel, although the actual price for solar energy is calculated by the power that they produce, and not the size or efficiency of the panel. Therefore, a 4kW system for a residential system will cost exactly the same as a 4kW system for a commercial system.

Because commercial panels are larger than residential ones, they are more efficient at producing electricity. Commercial panels have an efficiency of just under 20 percent, making them two percent more efficient than residential panels.

A non-stalling installation

In the case of both residential panels and commercial panels, they are installed using a bolted racking system, but as the roof of a commercial building is more more likely to be flat than the roof of a residence, a mounting system using non-penetrating ballast can be used, making installation easier. This makes a commercial installation easier than a residential one, although because many commercial installations can involve upwards of one hundred panels, as opposed to between eight and sixteen panels for a residential system, a full installation at a commercial premises can take longer than a week, or even as long as a month.

It's worth noting that if you are a residential customer who has decided to install a solar panel system, there is nothing to stop you from installing commercial-standard solar panels, especially if you have plenty of roof space, and you are not too bothered about how your panels will look on your roof. These are just some of the slight but important differences between a commercial and residential solar energy system installation. There is one thing that both types of system will have in common though – they allow the owners of the system to save money by using the free energy supplied by the sun, and they will both help to prevent global warming from becoming any worse.

If You Wish to Go Solar, Read This FAQs

Solar Panels Placed on Many Rooftops These DaysIf you have made the decision or are thinking about making the decision to go solar, then you may be wondering - how does sunlight actually get turned into electricity? You may have other questions too, such as will your solar panels work on cloudy days, and will your panels work at night via moonlight, which, after all, is reflected sunlight? To find out the answer to these questions and a few more, please read on. 

Q. How does solar power work?

The sun may be around 93,000,000 million miles away, but it is still a very powerful source of energy, and if you've even been sunburnt, you'll know just how powerful! Solar energy came about thanks to a chance discovery. While studying light, the French scientist Alexandre Edmond Becquerel noticed that when certain materials, such as silicon, absorbed light, they “knocked” electrons loose. From this observation, he perfected the photovoltaic (PV) cell, which was a device containing an electric field that made these “knocked” electrons flow in a certain direction, hence creating an electric current. Modern-day PV cells still use the same principle.

Q. Do solar panels work on cloudy days?

Yes, but less efficiently. The brighter the day, the more light arrives at the PV cells, and the greater the number of electrons that are sent flowing. If the sun is blocked by cloud, less light reaches the cells, and less electricity is produced. On a dull day, a panel will only produce between 10 and 25 percent of the electricity it can produce on a clear day.

Q. Can solar panels work by moonlight?

No, the sunlight reflected by the moon is too weak to generate any solar power. Your system will still power or at least partially power your home at night, as most systems come with a battery that stores some of the electricity generated during the day to be used at night.

Q. How long do solar panels last?

That depends on the manufacturer. Most PV solar panels have a lifespan of around 25 years, but can run for 40 years and beyond.

Q. Is there a need to keep solar panels clean?

Yes, there is. PV cells only work if they receive direct sunlight, so anything that is blocking them will prevent them from generating any electricity. This could be leaves and other natural debris, bird faeces, and of course in winter if your roof is covered in snow, your panels will not work. In general terms, it is probably worth having your solar panels cleaned once every couple of years or so.

Q. How much electricity does a solar panel typically produce?

That depends upon the kind of system you install. As a general rule, each 1kW of solar panels produces 850kWh of power in a year. Therefore, if you have a 4kW system, you will generate 3,400kWh of electricity annually, which is roughly worth about $400, and is enough to power nine big screen plasma TVs for a whole year.

Hopefully, that should have answered some questions you may have had about solar energy. If you wish to get more info, you can visit the Department of Energy Solar Website , which have plenty of information and resources

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