Solar Panel House with Solar Solar Farm
Member of Clean Energy Council

SOLAR POWER FREQUENTLY ASKED QUESTIONS 

 

Solar power is a fascinating subject and to newcomers can be a little confusing.  Hopefully our FAQ’s below can answer your queries.  If you have any other concerns, be sure to contact us and one of our expert consultants will provide you with answers.


  1. How long will my solar panels last?
  2. What about the inverter, how long will it last?
  3. What does grid connect mean?
  4. What affects the amount of solar energy produced?
  5. What about roof orientation.  Is north really better?
  6. How do I know if my building is suitable for a solar power system?
  7. What does it cost to install a grid connect solar power system?
  8. What is a grid feed-in tariff?
  9. What size system should I install?
  10. What warranty can I expect from Solar City Enterprises?
  11. What’s the difference between monocrystalline, thin film or polycrystalline solar panels?
  12. What affects the installation costs?
  13. What about protection for my system?
  14. Can I upgrade to a larger system down the track?
  15. What happens on cloudy days?
  16. Is there any maintenance involved?
  17. Is it a reliable investment?

1. How long will my solar panels last? [back to top]

Photovoltaic solar panels have been stringently tested over the decades.  There is a small reduction in power output with age mostly due to dulling of the glass surface.  Solar panels are expected to last 30 to 40 years.

2. What about the inverter, how long will it last? [back to top]

Electronic components such as the inverter are the most sensitive.  With normal use, and as long as the system installed has been properly designed and the inverter is not overloaded, the inverter should last 15 years or so before requiring service. The top brand inverters offer extended warranties for up to 20 years. 

3. What does grid connect mean? [back to top]

Grid connect solar is only available where grid electricity is available. The electricity produced by your solar installation directs the power back into the electricity grid. The electricity grid basically behaves like a big battery that stores the power your system produces. The solar panels send DC electricity to the inverter which converts it to AC electricity (usually all your household appliances run off AC electricity). By supplying power to the grid, in most cases the property owner receives a credit or a payment for that electricity. This may be in the form of a government subsidised grid feed-in tariff or a wholesale payment from the energy provider.

4. What affects the amount of solar energy produced? [back to top]

As solar energy is basically radiation from the sun, more energy is available in the summer months.  Regardless of the seasons, the amount of energy generated will be affected by the amount of contamination (such as dust and moisture) in the air, the amount of cloud cover and any shading of the solar panels. The average solar energy converted to electricity in most areas within Australia has been calculated to an average of around 5 hours a day.  Slight variations will occur dependant upon the installation of the system.

5. What about roof orientation.  Is north really better? [back to top]

Yes it is if you live in the southern hemisphere… A system with solar panels facing in a northerly aspect will be the most efficient resulting in a higher production of electricity. However, all is not lost if you don’t have a northerly aspect on your roof.  It just takes a little ingenuity to design an efficient system on an east west aspect.

6. How do I know if my building is suitable for a solar power system? [back to top]

There are a number of things to consider before ascertaining whether or not your property is a good solar site. Orientation, available space, shadows and your current electricity usage all have to be calculated into the equation. Regardless, just about every property is suited for renewable energy of some kind. 

7. What does it cost to install a grid connect solar power system? [back to top]

Cost will vary according to the size of the system. Any available government rebates would be deducted from these estimates. A small system of around 1.5kW starts at around $6,000.00. If you have a large home consuming large amounts of power, a system to provide all your electricity needs could well rise to over $25,000.00. With the cost of electricity skyrocketing, most systems will still pay for themselves within 6 to 8 years. Call us to find out how.

8. What is a grid feed-in tariff? [back to top]

A grid feed in tariff is where your solar energy system is connected to the electricity grid and the property owner is paid for the electricity their system generates by a utility or government agency. There are two different types of tariffs, net feed-in and gross feed-in. A net feed-in tariff pays for any surplus energy created by the system. A gross feed-in tariff pays for all the electricity produced by the system.

9. What size system should I install? [back to top]

The answer to this question is three fold, as there are three different scenarios to consider.


  1. In areas where there is no grid feed-in tariff, the best advice is to install a system large enough to provide all your daytime power usage. There's no point producing more than what you use during daylight hours if you don't get paid for any excess fed into the grid.
  2. Some regions pay a one for one. In other words, you receive a credit for any excess power produced during the day that you can claim back during the night. In this case, the best advice is to install a system that covers all the electricity you use. Check your bill for your average daily kWh usage and if you have the budget, have a system designed to cover that usage.
  3. The third scenario is where you receive a grid fed-in tariff, or a one for one with an excess tariff. In this case, you can install a system of any size that suits your budget. If you decide to install a system that delivers more power than you use, you will get paid for that excess.

We suggest contacting us (see our contact page) and discuss your situation with one of our professionals who can give you the best advice based on your power usage and budget.

Over and above the installation of renewable energy, it is a worthwhile exercise to implement energy efficient strategies. Using energy efficient lighting and appliances will significantly reduce energy costs. With the cost of power these days, it would be wise to look at these strategies.

10. What warranty can I expect from Solar City Enterprises? [back to top]

  • Solar Panels: All our solar panels have a 25-year performance warranty.
  • Inverter: minimum 5-year warranty on all inverters. Fronius inverters have warranty extension options that can be added to the standard 5-year warranty. Solar Edge inverters have a standard 12 year warranty.
  • Mounting System: 10-year product warranty (manufacturer)

11. What's the difference between monocrystalline, thin film or polycrystalline solar panels?
[back to top]

There isn’t a lot of difference between monocrystalline and polycrystalline panels. Monocrystalline is slightly more efficient and therefore the panel is slightly smaller than a polycrystalline panel.  Cost per watt is similar so roof space is usually the deciding factor as to which panel is used.  Thin film panels are much larger again and are considered a more efficient panel in shady conditions. Unless your property suffers from shade we would strongly recommend monocrystalline for grid connect situations.

12. What affects the installation costs? [back to top]

A standard installation rate is based on the system being installed on a single storey pitched metal roof in close proximity to the meter box, with no additional or major work required in the meter box. Additional costs will be incurred for a flat or tiled roof, two storey building, fitting solar panels on more than one plane, or any equipment/meter box upgrades and extended warranties.  

13. What about protection for my system? [back to top]

Most insurers will allow you to include the system under your home and contents insurance.  If in doubt, contact your insurer. 

14. Can I upgrade to a larger system down the track?  [back to top]

This is a simple, but at the same time complex question. If you install a system with the intention to increase to a larger system in the future, you need to research your initial installation. It’s easy to say “just add a few more panels” but if you haven’t planned for it, you may be in for a shock.

In most cases, the inverter will also need to be upgraded, which is an expensive exercise. So you’ve planned in advance and installed a larger inverter in anticipation of upgrading... Also a bad decision as an underpowered system will be extremely inefficient until you upgrade. If you really want to take this approach, then we suggest taking a good look at the inverter specifications.


  1. Traditional inverters: You need to start with an inverter that has a minimum of two MPPT strings, for example a 4kW SMA inverter has two 2kW MPPT strtings which means you can fill one string (2kW) now and get the maximum performance from that string, then add another 2kW at a later date. This scenario works but you must add the whole 2kW at a time to ensure you don’t lose efficiency throughout the process.
  2. Solar Edge inverter: All Solar Edge single phase inverters (up to 6kW) will function at 100% efficiency with just 1.5kW of panels connected. This gives you the flexibility of adding as much as you want or as little as you want at a time. That's right; you can add just one panel at a time until you reach the maximum. This is accomplished due to the Solar Edge philosophy of employing MPPT at the panels, not within the inverter.

15. What happens on cloudy days? [back to top]

On cloudy days with a grid connect system any deficit will be drawn from the mains grid.

16. Is there any maintenance involved?  [back to top]

A solar photovoltaic system is virtually maintenance free.  The face of the solar panels are treated and clean themselves every time it rains.  Every year or two it may be necessary to give the panels a clean with a soft broom.

17. Is it a reliable investment? [back to top]

A solar energy system has no moving parts, making it one of the most reliable investments of tangible product on the planet. With experts predicting the cost of power to increase by 15 to 20% per annum for the next 7 years, the return on investment will increase substantially each year. You will be hard pressed to find a better investment that not only saves you money, but helps our environment. It makes good sense.