Solar Buyer's Guide
How Does Solar Power Work
Solar power systems work by converting the sun’s light energy to usable electricity in your property.
To operate efficiently a solar power system requires direct sunlight, not just day light. The sunlight triggers a chemical reaction in the panels and as result DC power is generated.
The inverter then converts the solar panel’s DC power to AC power which you can use.
Solar power systems produce energy while the sun is out and if you don’t use this energy then it is sent back to the grid. If your system is producing more energy than what your home is using it will send energy back to the grid and your energy provider will pay you a feed in tariff (typically 6c to 11c) for each unit of electricity you send back.
If you wanted to use the solar energy your system is producing during the day, at night, then you would need to add a solar energy storage system to your solar system to store the energy for later use.
Solar panels used for residential purposes are usually 60 cell solar panels. Bigger 72 cell solar panels are also available however due to their increased bulk they tend to used mainly on commercial and government installations.
Solar Panels generally come with 2 warranties- a product warranty (which is typically at least 10 years) and a power output warranty (which is typically 25 years). It is important to note the key warranty is the product warranty, as this is the warranty you will be claiming on if your solar panel fails. The power efficiency warranty is a guarantee of the rate of degradation of the output of the solar panel over time.
You’ll often hear the term Tier 1 used to described solar panels, it is important to note that this is not a measure of the quality of the solar panel, rather it is a measure of the financial position of the solar panel manufacturer as rated by Bloomberg Finance.
When Purchasing A Solar System You Need To Ensure That The Solar Panels Meet The Following Guidelines:
- They are Clean Energy Council approved
- They meet Australian standards (AS5033:2014)
- They are covered by a minimum 10 year product warranty
- They are rated Tier 1 by Bloomberg
- The manufacturer has an office in Australia (for warranty claims)
The job of the Solar inverter is to convert the solar energy from your panels into usable AC power. The inverter is the brains of your solar system and regulates the flow of electricity from your panels into your property and into the grid.
When Purchasing A Solar Inverter You Should Always Ensure The Following:
- Clean Energy Council approved
- Meet Australian standards (AS4777:2015)
- Offers a minimum 5 year product warranty
- Have an office in Australia
There Are 3 Types Of Inverters That You Can Choose From When Purchasing A Solar System:
Standard String Inverter
This type of Solar inverter is the most popular and is a wall mounted box that ideally sits next to your meterbox.
With this type of inverter, solar panels are connected onto one of two strings of cabling that run into the inverter.
If you wanted to add a solar energy storage system (battery) to your system with this type of inverter, you would also need to add a battery inverter and an Energy meter to enable the operation of the battery.
Hybrid String Inverter
Hybrid inverters are growing in popularity and can output both DC and AC power.
Hybrid Solar inverters connect to your panels via strings the same as a standard string inverter, however the main difference is because they can output DC power, a battery can be plugged straight into them without the need for additional components.
If you are looking to add a solar storage system (battery) to your system then a hybrid inverter is the best solution.
Solar Microinverters remove the need for a central wall mounted solar inverter near your meterbox.
They attach to the bottom of each solar panel and each solar panel requires its own microinverter. This allows each solar panel to operate independently.
With microinverters there is no single point of failure, so if you experience trouble with a single solar panel it won’t affect the other solar panels in your system.
Microinverters allow more flexibility in placing of solar panels on the roof and perform better if your solar panels were subjected to partial shading.
Microinverters are battery compatible, however you need to use the relevant battery for the brand of microinverters you are using, or use an AC coupled battery inverter.
Solar Power System Production
When calculating a solar system’s daily production in Australia, we generally look at the kW rating and multiply this by the annual daily irradiation rate. So a 5kW solar system installed in Sydney will produce an average of 20kW per day over the course of a year- this will be higher in summer and lower in winter.
Solar Power System production will drop if it is overcast or raining, as the amount of sunlight hitting the panels will be greatly reduced.
With a string type solar inverter setup, your solar system is only as powerful as the weakest panel on that string, so if you have a single solar panel affected by shade this could bring down the production of your entire system- it is important to identify any shading issues and ensure solar panels are installed away from shaded areas. Even partial shading can have a huge affect on your solar system’s production.
To ensure the best production from your solar system, your solar panels should ideally be facing North, as this will maximise the sunlight hitting the solar panels during the day. West facing and East facing solar panels are also acceptable, however you need to avoid placing any panels on South facing roofs.
Solar System output is limited by the size of the inverter, so a 5KW solar inverter will not output any more than 5kW at a time- even if it is connected to 6kW of solar panels.
To ensure you maximise the return on your investment, you need to have a solar system that is suitable for your use. If your solar power system size is too small then you will continue to pay high electricity bills and if your solar power system is too large then you will be sending a lot of your energy back to the grid and hence increasing your payback period.
To calculate the ideal solar power system size, you need to identify what your daily energy usage is. You can find this on your electricity bill usually labelled as average daily usage.
This figure is your usage for the whole day (day and night), the next step is to identify what portion of this your energy you use during the day. For example if your average daily use is 40kW and you use 40% during the day, this equates 16kW of use during the day. So in this scenario we would look at 4kW to 5kW solar power system.
Beyond Solar will always recommend a solar system that is in line with your usage so that you get the quickest possible payoff period.
Batteries store the energy produced by your solar system for use when the sun isn’t shining.
All solar systems are generally compatible with a battery, however, you may require additional components before you can connect a battery if you don’t have a hybrid inverter, which can add up to $2,500 to the cost of the battery.
Batteries are available in a variety of sizes and also come in high voltage and low voltage options. You need to ensure your battery is compatible with your inverter.
Before committing to a battery system is important to identify that you are producing enough solar energy to charge the battery. If you are using all the energy your solar power system is producing then adding a battery won’t help as you won’t have any surplus energy to charge the battery, For example having a 3KW solar system would produce on average 12KWh per day, Installing a 10KWh energy storage system would mean that you must use very little power during the day to allow the battery to sufficiently charge otherwise your battery may never fully charge and in return affecting your payback period.
If this is the case then you may need to increase the size of your system to allow for enough energy to charge the battery.
Beyond Solar only uses batteries that meet Australian standards and have a minimum 10 year warranty.
Choosing An Installer
When choosing an installer it is important to ensure that they are going to deliver quality work and be able to help you if things go wrong in the future.
It is important that you go online and read reviews of different solar companies. You should read both the positive and negative reviews. Positive reviews will show who has had a good experience and what the company did well which is important.
Just as important though is to read the negative reviews- no business is going to get things right 100% of the time so the important thing to look for when reading a negative review is how the company handled the issue- Did they resolve the issues with the client? Did they take responsibility? Was the customer happy with the outcome? If they did then you can be assured that if things did go wrong they will address your issue and fix it.
Other Things To Look Out For When Choosing Which Solar Company To Go With Are:
Are they a CEC approved Retailer?
Companies that have signed on to the code have committed to provide a higher standard of quality and service, raising the bar in the solar industry. They will also provide a minimum five-year whole of system and installation warranty on solar power systems.
The program is designed to give peace of mind to people who are making the decision to invest in a solar system by helping them purchase the best product available from a company committed to responsible sales and marketing.
Beyond Solar has signed on to the Clean Energy Council Solar Retailer Code of Conduct, a voluntary scheme authorised by the Australian Competition and Consumer Commission (ACCC).
Do they offer a workmanship warranty?
This helps protect you if there are issues with the conduit, cabling or mounting of the panels. Beyond Solar offer a 10 year workmanship warranty on all systems we install.
Do they offer after sales support?
Installing the system is one aspect, but what if your wifi goes out or your system isn’t producing what it should. Beyond Solar offer after sales support for the life of your system.
Are there any hidden costs?
A good company will ask about your home- is it a double or single storey, what material is your roof made of, how far is your meterbox from your home. These sort of questions allow them to provide accurate pricing on your system with no hidden costs. Avoid a company that gives you a base price and then when they come out start adding extra hidden costs. Beyond Solar will never add any additional hidden costs to our quotes, that’s our promise.
What’s been your experience dealing with them?
Have you found them to be honest and upfront when dealing with their sales people? The sales people can reflect the culture of the organisation so if they are avoiding answering questions or not being transparent then you need to consider going elsewhere. Beyond Solar will take the time to address all your questions and concerns and ensure you are comfortable with the solution we are proposing.
Have they specified which components they will be using?
Have they specified which components they will be using? It is important that the brands and specs of the components being used in your system are detailed in the quote. If a company is vague about the brands used or lists multiple brands that maybe used in your installation, then get them to provide specifics in writing before you commit. Beyond Solar will always detail what brand components we will be using in your solar system.