Solar Introduction
How does solar save me money?
When does solar produce power?
Using solar power during the day
I’m not using much power during the day is solar still worth it?
Installing Batteries (Hybrid)
How to size my solar system?
Go bigger or try and match my daytime usage?
Overloading your solar inverter
Is the best price the best investment?
What System is best for me?
Return on Investment Examples
Going solar vs. Not going solar
Zero out of pocket solar – financing your investment?
Are there still rebates for installing solar power?

Solar Introduction

Solar panels convert sunlight into DC electricity, the inverter then converts this to AC electricity so it can be used at your property or fed back into the grid if you don’t require the power. Here at Adapt Energy we specialise in grid connected & hybrid solar PV (Photovoltaic). Solar Photovoltaic (Solar PV) is the technical term for solar electricity panels and it refers to the conversion of light into electricity. The hybrid part is referring to batteries, the reason its hybrid is because you have the best of both worlds with batteries and grid power instead of relying 100% on one or the other. Batteries are becoming increasingly popular and many of our clients are opting to go that way but many are still starting with grid connected solar for the time being with the view to add batteries in the future.

How does solar save me money?

Once you have solar PV installed any power you use during the day will primarily come from the solar system.  Any excess energy the solar system produces will be fed back into the grid and your retailer will purchase this energy from you and this will appear as a credit on your bill (subject to approval). If you require more power than is being produced by your solar system, you will pull it from the grid as you do now.

The rate of power is now generally higher than the feed in tariff offered for excess power fed into the grid. This is why in order to maximise your savings it is beneficial to use the energy that you require during the day.

When does the solar system produce power?

Solar produces power during daylight hours and will start producing power as soon as light touches the array. The hours of production vary depending on your location and the system design but an example might be 7am-5pm. In order to work out your systems average daily production on a conservative basis multiply the panel output by the figure relevant to your location:

Adelaide 4.2
Alice Springs 5.0
Brisbane 4.2
Cairns 4.2
Canberra 4.3
Darwin 4.4
Hobart 3.5
Melbourne 3.6
Perth 4.4
Sydney 3.9
  • 6.5kW System x 4.2 = 27.3kWh/day
  • 8.5kW System x 4.2 = 35.7kWh/day
  • 10.6kW System x 4.2 = 44.52kWh/day
  • 32kW System x 4.2 = 134.4kWh/day
  • 100kW System x 4.2 = 420kWh/day

This average daily production will vary depending on the time of year and the weather conditions of course. On a clear summers day this figure can potentially be over 50% greater and on a dark cloudy winters day the production can be considerably lower. The system gradually builds up in the morning and increases production to the middle part of the day and tapers off later in the afternoon. It produces power like a bell curve on a graph with the best production in the middle of the day between around 9am & 3pm.

See the examples below with the green being power fed into the grid, the grey being solar energy consumed on site and the black line being the 24 hour energy consumption.

5.4kW residential example

32kW Commercial Example

Using solar power during the day

For residential households, many people would be out for large parts of the day and the majority of the power currently consumed may be first thing in the morning and later in the day. There are many options for adapting your usage to benefit more from the solar energy produced. Fridges and freezers will run 24/7 and often use more energy during the day when its warmer but there are a few more tips to utilise the solar energy:

  • Put a delay start on washing machines and dishwashers
  • Put your electric hot water system on a timer (we can do this on the day of the solar installation)
  • Use energy at weekends (ironing, vacuuming, washing etc)
  • Run your pool pump in the day on a timer
  • Install panels facing West so they are performing better in the afternoon when you are using power

I’m not able to use much power during the day, is solar still worth it for me?

Although the feed in tariffs are generally lower than the price of power, even if you don’t use a large portion of your energy during the day installing a larger system and more feeding the excess energy back to the grid can still offer a very attractive return on investment. With increasing feed in tariffs on offer of 10-16c/kWh even when only using 20% of the energy produced during the day, you can still often achieve a return on your investment within 5 years.

Use our solar savings calculator to work out your savings and return on investment.

Installing batteries (Hybrid)

Installing batteries is a great way to further reduce the amount of energy you purchase from the grid. Once you have batteries installed to your grid connected system you now have a hybrid system. When you have excess energy being produced it will be used to charge your batteries and once fully charged the excess energy will be fed back into the grid. Your primary source of energy will still be the solar system, then secondly when required (generally at night time) you will use your batteries, then finally if required you will use grid power.

How to size your solar system?

Roof Space

Your roof space determines the size system you can install. North facing panels will produce the most energy overall but with current panel technology and performance in lower light conditions, East and West arrays also perform almost as well. In fact in some cases East/West installations are favourable as the system then produces more power at the times when energy is required (mornings & afternoons).

One of our consultants will assess your roof space and inform you of the most suitable design, which is flexible to your requirements and confirmed upon the site visit from the installer.

Your Usage

Your energy consumption is a factor when deciding the right size system for you. Check your power bill and look for your average daily usage which will tell you what you’re are using per day for a 24 hour period. If this figure is not displayed you can take your total kWh usage and divide it by the number of days for that bill. 

Ergon Bill Example

Origin Bill example
AGL Bill example

The portion of this energy you can use during daylight hours is a contributing factor when deciding the most suitable size system and how much it is likely to save you. Ideally the solar system will produce at least enough to cover your daytime power. How much of your power that is consumed at night time can be used to decide on what battery size is going to be most suitable, if you decide to go that way.

With residential and smaller commercial properties your daytime usage is not necessarily the deciding factor for the size system you choose because the excess energy is being sold into the grid.  You may find the larger system is better value and with exported power can save you more in the long run. If you don’t have batteries the higher your daytime consumption, the more you will save. If you are not using much power during the day it is certainly an option to consider a smaller system such as a 3kW to offset your daytime usage but most of our clients are seeing the value in 5kW plus size systems.

It often makes sense to utilise as much of your roof space as possible due to the increasing feed in tariffs and up front rebates on offer. For example with a 6.5kW system producing an average of 27.3kWh per day, even if you used just 20% of this power (5.46kWh per day) and the rest went back into the grid (21.84kWh per day) you can still achieve a return on investment in under 5 years and save over $1,300.00 per annum.

Grid Approval

We can submit a grid application for you free of charge to find out what system size you can install and how much you can to export but generally speaking the restrictions on inverter capacity are as follows:

  • Residential 10kW per phase with 5kW export limit on single phase (single phase is most common)
  • Commercial – up to 30kW to qualify for full export with feed in tariff
  • Commercial 30kW plus – Export limitations normally apply

Residential single phase properties can now install up to 10kW inverter capacity and up to 13.3kW of solar PV resulting in savings of up to $6000.00 per annum if all the energy can be consumed during the day. Even if only 30% of the energy is consumed, the 13.3kW system could still save over $3000.00 per annum and allow you to break even well within 5 years. This is great news for those higher users. 

Go bigger or try and match my daytime usage?

With residential or smaller commercial buildings often the largest system possible offers the best long term investment. This is because the upfront rebate (STC’s) is offered based on the panel capacity, so the larger the system the larger the rebate. This often makes the larger systems (6-30kW) better value for money. Also, with increasing feed in tariffs you effectively get paid for what you sell back to the grid and this can offset large portions of your evening usage and supply charges.  With larger commercial properties we tailer the system to to fit your usage as accurately as possible as there is generally no feed in tariff offered on systems above 30kW inverter capacity but we will look at this case by case.

Larger system pro’s
  • Larger upfront rebate
  • Better value
  • Greater overall savings on the bill
  • larger system ready for batteries in the future
  • Once broken even greater savings moving forward
  • Offset/reduce costs of evening usage & supply charges with energy sold to the grid
Larger system con’s
    • Larger upfront investment (only if paying cash)

(Have you considered finance – your system could simply pay for itself?)

Smaller system pro’s
  • Can sometimes offer shorter return on investment
  • Less money upfront
Smaller System con’s
    • Less overall energy savings
    • Less opportunity to store energy for batteries
    • Adding panels later is more costly

The benefits of going big – residential solar 16.9kW – Case Study

Overloading your inverter

Panels very rarely run at 100% efficiency so in order to get the most out of your inverter capacity you can oversize it by up to 33%. This allows you to reach a higher production level earlier in the morning and maintain it later in the afternoon. It also means when it is a bit cloudy your extra output can make up for some of the losses.

Common examples:

  • Residential 6.5kW (PV) with 5kW inverter
  • Residential 10.8kW(PV) with 8.2kW inverter
  • Residential 13.2kW(PV) with 10kW Inverter
  • Commercial 39kW (PV) with 30kW inverter

Is the best price the best investment?

Getting solar installed for the best price will make the return on investment seem very attractive and the numbers will stack up very well on paper. This is often too good to be true in reality. Solar is an investment and its all very well your system paying for itself in under two years but if the system breaks down shortly after, the whole exercise has been pointless. You have to consider the quality of the system, the level of workmanship provided and the ongoing support from the installer and the manufacturer of the equipment within Australia.

It comes down to how long you intend on keeping the property or staying in the premises.

What system is best for me?

Although in order to maintain the highest possible standards we refuse to compete on the absolute bottom of the market, we have a wide range of products to suit all budgets. All of our systems are high quality and would offer a great investment in the majority of cases but one of the main factors when deciding if its worth spending more on a system is how long you are going to keep hold of the property. If you are going to be in the property for 10 years plus the extra 5-10% production you can get from a top of the range system will provide you with a better financial return in the long run. Secondly, the reliability and build quality you will get from the top of the range system will result in a longer lasting, hassle free system for up to 25 years and beyond.

  • Going to keep the property for up to 3 years? – Go Value
  • Going to keep the property for 5-10 years? – Go Premium
  • Going to keep the property for 10 year plus? – Go Platinum & consider batteries

Return on investment Examples

This is based on our standard price for a 6.5kW system with the price of  power at .28c/kWh (inc gst) and the feed in tariff at 10c/kWh.

Value system
  • 50% usage of solar energy during the day
  • 2.18 years payback
  • 45.87% ROI per annum
Premium system
    • 50% usage of solar energy during the day
    • 2.79 years payback
    • 35.84% ROI per annum

Platinum system
  • 50% usage of solar energy during the day
  • 3.06 years payback
  • 32.68% ROI per annum

For a more detailed breakdown of your savings and return on investment see our solar savings calculator. These figures are one of the reasons our top of the range Platinum Solar Package is our best selling option. The reason being is that you can have one of, if not the best solar system on the market whilst achieving an exceptional return on investment. Once you have broken even you really do have a system you can rely on that will continue to perform at the highest possible level for many years to come.

Going solar vs. Not going solar

Just to put it into perspective your energy costs are inevitable and have increased exponentially over the years. The price of power is at an all time high and Australia has some of the most expensive prices for electricity in the World. If you can own your own energy station producing renewable energy your costs will be heavily reduced in the long run and you will ultimately be left with more money for yourself, your family and/or your business. If you have the money to invest in solar and purchase the system outright you can achieve a far better ROI than having the money in a savings account with most people achieving 20-30% per annum. On the other hand if you don’t have the spare capital why not use the money you are already budgeting for power and redirect it towards your own solar system.

Zero out of pocket solar? – Financing your solar investment

Solar doesn’t have to be a financial burden, in fact with a simple green loan or lease to own package your repayments are likely to be less than what you are saving from the solar system.

6.5kW Example - 5 year term


$ 190.71

Per Month (Based on 70% solar usage)


$ 135.61

Per Month

Cash flow difference

$ 55.10

Per Month (in front)

With this example the customer would be better off by $55.10 per month whilst paying the system off. Then in 5 years time, the repayments would stop and the customer would be $190.71 per month better off even if the price of power stays the same. If the price of power increases the effective savings also increase.

We have a wide range of finance options to cater for individual requirements from Certegy payment plans (now Humm – Buy now pay later) and Green Loans to commercial lease to own and chattel mortgage options.  If you prefer, your own bank or broker may also be able to offer a suitable option. Our solar savings calculator has a finance calculator at the bottom so you can compare your savings & repayments. Contact us to discuss the best package for you.

Are there still rebates for installing solar power?

When you have a solar system  installed by a Clean Energy Council accredited installer using a Clean Energy Council approved Inverter & Panels (< 100kW) you will be eligible for the STC (Small Scale Technology Certificates) program. This is a Federal Government scheme that is being reduced by one fifteenth at the end of each calendar year from 2017 until is reaches zero in 2032. This is for the number of STC certificates eligible for each system which also varies depending on your location and it’s average amount of sunlight. The price of each certificate also fluctuates and varies depending on demand from 0-$40 (the lowest its been was around $17). The rebate is currently at a very healthy price but could potentially drop significantly at any given point. This is why its advisable to secure your STC (“rebate”) price while it’s still high.

The larger the system, the greater the number of STC certificates that will be eligible.


  • 3kW system = 50 STC’s at $36 each = $1,800.00
  • 6.5kW system = 107 STC’s at $36 each  = $3,852.00
  • 10.8kW system = 178 STC’s at $36 each = $6,408.00
  • 33kW system = 545 STC’s at $36 each = $19,620.00
  • 99kW system = 1,635 STC’s at $36 each = $58,860.00

The STC’s will be offered as an up front, point of sale discount for the solar system and installation.

Contact us and we will provide you with a quotation including your STC discount.