Solar Electricity Explained

Electricity is simply a flow of electrons running around a closed circuit. So how do we create a flow of electrons using solar panels and the sun? Well, the internal workings of solar panels are quite complex, but here’s a quick rundown:

The photons which make up light, zoom into the solar panel and dislodge electrons from their resting place. These electrons then hitch a ride on a specially created magnetic field which gets all these loose electrons flowing in an electrical circuit. This is called the photovoltaic effect. All you really need to know is that the solar panels on your roof take the sunlight, and produce electricity.

The electricity is captured by heavy duty wires and fed into a box of electronics called an ‘Inverter’. The primary purpose of the inverter is to boost the fairly feeble flow of electricity (known as ‘low voltage direct current (DC)’) into nice, clean and reliable, high voltage 240V alternating current (AC) electricity that is compatible with both your household appliances and the electricity grid.

Any of the electricity that comes out of your inverter that is not used by your house and gadgets will, by the natural forces of physics, flow backwards through your electricity meter (very usefully, and legally, actually spinning your meter backwards!), and out into the national electricity grid. This process differs slightly if you are eligible for a feed in tariff, as explained on the solar panel installation home page.

Solar Electricity Systems Anatomy

1. Photovoltaic (PV) Panels

These are the most expensive part of the system and will typically make up 60% of the cost of your system. They simply take sunlight in and produce electricity. However that electricity is in a form that is not very useful to you – Low Voltage, Direct Current (DC) Electricity. To make it compatible with our appliances it travels via high current cables to what’s known as an Inverter.

2. DC to AC Inverter

This is a box of tricks that takes the raw DC electricity from the panels and boosts its voltage to a nice 240V AC so that it will power all your appliances and gadgets. The inverter can come with some really nice features, such as:

Power Monitoring: A little display on the inverter will tell you how much power you are generating at any one time.

Remote Power Monitoring: A separate display that wirelessly receives monitoring signals from the inverter. This means you can sit in your favourite chair and monitor your power production. The remote display will even have some logging functions so you can look at power use over time, and see how the weather, etc… affects your solar electricity systems performance.

PC Interface: Links to your PC and the Web so you can view your system status from anywhere, and do various graphing and analysis of your power generation.

Expandability: If you think you may want to expand your system at a later stage, you should get an inverter that is expandable. That means that you just plug in an extra module (solar panel array), instead of having to buy a new (bigger) inverter.

3. Wiring From Inverter To Fuse Box

You need to get your new electricity into the house and the grid, so that’s where this new wiring comes in. A disconnect switch is needed in case you need to isolate the solar panels for maintenance, or if something goes wrong with them. This switch will simply stop the solar system from feeding your house, and the electricity grid (for any number of reasons).

4. Main Fusebox Connection

You most likely won’t need a new fusebox, but your new system will be wired into your existing fusebox. This allows your solar electricity to feed into the house wiring for use.

5. New Electricity Meter

You will need a new electricity meter to cope with importing and exporting solar electricity to the grid. Your electric utility company will install this for you. Be aware: The utility may use this as an excuse to put you on a ‘time of use’ electricity tariff. This means that you may pay different amouts for electricity depending on when you use it. The good news is that if you use your appliances intelligently this can actually reduce your bills further. But you need to know what you are signing up for. Be sure to have a good chat with your utility about this, we’ll point you in the right direction (as any expert solar panel installation company should).

Solar Electricity Panels

When shopping around for a solar installation for your home, business, or industry… you will need to assess what kind of panels are best for you. Here are some of the factors you should weigh up:

Solar Panel Efficiency – We are talking about the ratio (as a percentage) of energy in the sunlight hitting the panel area – to – electrical energy in the wires coming out of the panel. Why is a high efficiency good? Well the higher the efficiency, the more Watts of electricity you will get per volume of material used in the solar panel. So generally speaking, the higher the efficiency the cheaper, that type of solar panel becomes for the same electrical output.

Does that mean that you should just choose the panel type that has the highest rated efficiency percentage? It’s not that simple because some panel types cost more to manufacture than others, they can still turn out more expensive that other types with a lower efficiency. So if you are going on price alone you would look at the Watts-per-dollar figure instead.

Solar Panel Cost – The obvious calculation here is “How many watts of electricity are you getting per dollar of panel?” But bear in mind that different panels degrade at different rates, so although some panels give a great cost-performance ratio up front, look at what performance is guaranteed, 5, 10 or 20 years into the future.

Solar Panel Toughness – Is there likely to be a hail storm over your house in the next 20 years? Thought so. Make sure your panel uses tempered glass that will withstand a direct hit.

If you would like more information on solar electricity systems to discover how installing one would benefit you, your wallet, and the environment… then take a few seconds to contact us for a FREE quote and information pack. The time is now!