1 - What does ‘PV’ mean?

PV’ is shorthand for Photovoltaic. This is the technology that allows sunlight to be converted into electricity via solar panels. These panels use wafers of silicon to convert the photons of sunlight that hit it into Direct Current (DC) electricity. This DC electricity then runs through the wiring and into an inverter, where it is converted into Alternating Current (AC) which can be then used in your house.

 

 

 

 

 

 

2 - How much electricity do PV systems generate?

The capacity of a PV system is stated in terms of the number of watts, kilowatts, or megawatts it can produce in standard sunlight conditions. For example, in the ACT each kilowatt (kW) of solar energy installed produces about 1,500 to 1,600 kilowatt-hours per year, depending on the angle at which the panels are mounted.

 

 

 

 

 

 

3 - What is the Solar Premium?

The Solar Premium, also know as the Feed-In Law, is a '...legal obligation on utilities to purchase electricity from renewable sources' (Source: European Environment Agency). The ACT Government is currently looking to the possibility of implementing this. See a more detailed description of the Solar Premium.

 

 

 

 

 

 

4 - What do the terms watts, kilowatts and kilowatt-hours represent?

A watt is a unit of power. A kilowatt is one thousand watts and a megawatt is one million watts. A watt-hour is a unit of energy, or power multiplied by time. A kilowatt-hour is one thousand watt-hours and a megawatt is one million watt-hours. The electricity you purchase from the utility is measured in kilowatt-hours (kWh). Most family homes in Australia use 20 kWh or more per day. A refrigerator uses 1.2 kWh per day and a computer uses 2.4 kWh per 8-hour workday.

 

 

 

 

 

 

5 - What percentage of my electricity will my PV system generate?

That depends on how much electricity you use in a year. You can calculate this by adding the kilowatt-hours (kWh) found on your monthly electricity bills during the past year. Or, you can call your electricity provider for a history of your electricity consumption. Once you have that number, divide the expected annual output of the PV system by your annual consumption. In most cases, PV systems are designed to be supplementary sources of power.

 

 

 

 

 

 

6 - What is the difference between AC and DC electricity?

Alternating current (AC) electricity is the type of electricity that runs off the powerlines and grid in Australia. It is the type of current that is used by everything in your house. The voltage of this electricity is constantly alternating. PV systems, however, produce direct current (DC) electricity, which has a constant voltage. This electricity has to be converted to AC by a piece of equipment called an INVERTER in order for it to be used by the appliances in your house. The wires and inverter causes a slight loss of energy, so the AC output is about 80% of the DC electricity generated.

 

 

 

 

 

 

7 - How long does a PV system last for?

The componentry of a PV system has been refined over decades now with durability and longevity as a primary focus. As a result, solar panels are usually guaranteed for 20 years, and have an assumed working life of 30 years.

Inverters are more delicate than the panels, and many are guaranteed for around 5 years. However, as they have no moving parts and if they are placed in a part of your home that gets little moisture and dust, there is no reason why they should not last much longer.

 

 

 

 

 

 

8 - Do I have to select certain appliances to be powered by the PV system?

No, the solar electricity is fed through your main electrical distribution panel and can be used by any lights and appliances just like electricity from your local utility.

 

 

 

 

 

 

9 - How much roof space do I need for a PV system?

A typical PV system requires about 7 square metres for every kilowatt installed on a pitched roof, and up to 9 square metres per kilowatt on a flat roof. PV systems should be installed facing North for maximum electricity production.

 

 

 

 

 

 

10 - Do the solar panels have to stick out from my roof so much?

The reason that many solar arrays are so prominent is that the owner is determined to get every last photon out of the sunlight that hits the roof. If you are not concerned with absolute optimal performance, the panels can be attached flush to your roof. This is a much more subtle means of attachment and is preferred by people who want to keep the aesthetic line of their roof, or who want to not advertise the fact that they have a solar array.

 

 

 

 

 

 

11 - Will a PV system cause my roof to leak?

Most flat roof installations do not require penetrations, and therefore do not increase the chance of leaks. A PV system can actually protect a flat roof beneath it from ultraviolet rays and leaks. A pitched roof installation will require penetrations, but each hole is protected by standard roof flashing and the chance of a leak is not increased.

 

 

 

 

 

12 - I have an unusual roof, am I able to attach a PV system to it?

Mounting systems have been devised for practically every type of roof surface. Tiles, cliplock and colourbond are all no problem. However slate and shingle roofs, because of their fragile nature and the way they are attached to the roof battons are not able to have a mounting system attached to them. As soon as this is remedied, we will notify you on this website in large letters.

 

 

 

 

 

 

13 - Are PV systems expensive?

Systems of any kind that safely produce electricity are expensive. When you buy a PV system, you are effectively buying electricity for the next 30 years or more up-front, avoiding future electricity price volatility. Solar electricity is also a premium grade of electricity because it is generated without giving off any pollutants. This makes it more valuable and more expensive than standard utility electricity.