How much energy will my solar cells produce?

The electrical energy output of solar cells is obviously one of the crucial things that you need to know when looking to install a solar system. Some solar energy companies are giving a wide variety of unreferenced numbers, so we have done our research and provide you with fully referenced and reliable information for you to consider.

What is energy output?

The power rating of your system (kilowatts, or kW) is a measure of how big your generation system is, not how much it will produce. This is analogous to a car engine, where the size of the engine gives you an indication of how powerful it is, but does not itself tell you how much petrol it will use, although the two are related.

Whether or not you have access to a solar feed-in tariff (keeping in mind that all of the feed-in tariffs in Australia have been closed to new applicants), you should know how many (kilowatt-hours or kWh) your solar system can be expected to produce. Knowing this number will help you calculate the revenues and savings you can expect to receive from your solar panels.

What factors influence solar system energy yields?

Of course the first factor influencing how much electrical energy you will generate is the size (otherwise known as rated power) of your solar installation. A large installation (higher kW’s) will produce more electrical energy (just as a bigger car engine has more grunt).

But if we move past the obvious impact of size, the amount of energy your solar cells produce depends on how much fuel they are fed (just as the amount of energy a car engine will produce depends on how much petrol you pump into it via your foot on the throttle). In the case of solar PV cells, their fuel is the sun.

The amount of sun your solar cells are exposed to (and hence how much energy they will generate) depends upon:

  • The orientation and tilt of your installation (which will be optimised by your installer)
  • Whether there are shadows cast over your cells (due to trees, buildings etc)
  • The number of daylight hours (governed by where you live)
  • The intensity of the sunlight (governed by where you live)
  • The number of hours of full sun vs cloudy days (governed by where you live)

If we exclude the first two factors, which you have a degree of control over, your location in Australia is the primary variable dictating how much energy your cells will produce. Hence, a 1.5kW system in Melbourne will typically not produce as much electrical energy over the year as the same system in Alice Springs.

The figures for average daily production

Fortunately, studies have been conducted that take all of the above factors into account and give the average energy output for solar cells in locations around Australia. These figures are given as:

The amount of electrical energy (kWh) a 1kW grid connected solar PV system will generate on an average day (kWh/kWp.day).

The most comprehensive source of this information is the Clean Energy Council (the body that the Australian Government charges with accrediting solar cells, inverters and installers):

Average-Daily-Production-of-Renewable-Energy

Average daily production of solar PV cells in Australia
p4, “Electricity from the sun: Solar PV systems explained” by the Clean Energy Council

Researching this topic will reveal other credible sources, with slightly different figures. The USA’s National Renewable Energy Laboratory’s (NREL) PVWatts tool also works for Australia (using Aussie meteorological data) and is a great resource for plugging in numbers and estimating a solar system’s output. We encourage you to check it out.

Some exploration will reveal that it’s not quite possible to put an exact unequivocal figure on the energy you will produce from you solar cells. Indeed, as Dr Anna Bruce, Lecturer at the School of Photovoltaic and Renewable Energy Engineering at the University of New South Wales informed us, different solar systems both rated at 1kW sitting side by side may produce different amounts of energy due to the quality and efficiency of their components, how the grid is functioning and how well your system deals with high temperatures. Her expert advice is that “4kWh/kWp.day in Sydney is certainly feasible if a system has optimal tilt and orientation and is running well”.

So the Clean Energy Council figures above act as a good guide and are one of the best and most comprehensive sources available, however due to the nature of solar, your system may produce more, or a little less than the figures given.

*This article was originally posted in 2010 and has been updated in April 2019 to reflect any changes or updates.

© 2019 Solar Choice Pty Ltd

Comments

  1. What’s up everyone, it’s my first pay a quick visit at this website,
    and post is genuinely fruitful for me, keep up posting these content.

  2. On my 4kW, 22-panel Sunny Boy/Suntech system, my early estimate was to produce a high of 21kWh/day and low of 17.3kWh/day.
    This compares with the reality of 21.5kWh/day in 2011, slowly reducing to a current 19.9kWh/day, still well above the Perth estimate of 17.6kWh/day which I’m satisfied with!

  3. Hi,
    I have 3.6Kw inverter with 20 Solar panels and doing ok with it but I am thinking to buy a 500W Wind turbine that I can use during the night if there is any wind.
    Is this possible to implement? I can’t find any information about it or anything mentioning restrictions on it so I assume should be ok.
    I live in Perth.
    Any comments from anyone?
    Thank you.

    1. Hi Orlando.
      You will need to get planning approval to install a wind turbine. So enquire with your Local Council or State Department of Environment to see if it possible for you.

  4. I just want to commend whoever it is that is answering the questions on here, your attitude and the information you provide is spot on.
    Cheers
    Jeff

  5. Hi, I’m in Brisbane and have a 3.5kw system(20 panels) and wondering what daily output I should expect at this time of the year.
    Cheers Gary

    1. Hi Gary,

      This time of year you can reasonably expect around 3 kilowatt-hours (kWh) per kilowatt (kW) of solar capacity (assuming that your roof faces due north and has no shading and that your system loses about 15% in energy yields due to inefficiencies).

      In total that works out to about 10-11kWh per day for this time of year.

      For more info, check out the PVWatts calculator.

      Hope this helps!

  6. In determining our solar needs we are looking to manage our electricity consumption during daylight hours to keep it below the a-point-in-time output from the solar installation in kilowatts, not kW/hours. Thinking about kW generating capacity, and accepting inefficiencies of the system due to sunless days, we are more interested in covering usage cost than FiTs. Are we misguided, please?

    1. Hi John,

      You are absolutely on the right track: for anyone going solar now, using the solar energy directly in the home is the best way to save money. This is called ‘solar self-consumption‘ and it’s a must for solar system owners these days. Feed-in tariffs are a bonus.

      A home energy management system is what we generally recommend to people looking to maximise self-consumption. These days they’re relatively affordable and can really help to make a difference within the home.

      Hope this helps!

  7. Was after some advice..have installed a 5kw system in townsville however just got our power bill and was at a loss of the amount we “saved”.
    In the quarter it is saying we generated 856 kwh.. is this realistic or is there a probkem with our system. Thanks

    1. Hi Nathan,

      What you see on your bill will only reflect the amount of solar energy that you’ve sent to the grid (‘solar export’) – you get a credit for each unit (kWh) of solar that you send into the grid. What will not show up on your bill is the amount of solar energy that you’ve used directly inside your home (‘solar self-consumption’). Solar self-consumption is actually the main way to save money with solar these days – basically, every unit of solar that you use yourself is one less unit that you have to purchase from the grid. Unfortunately the amount of solar that you’ve self-consumed over the billing period will not appear on your bill (as your retailer only shows you energy flowing in and out of your home).

      To get full insights, you need a solar/energy monitoring or energy management system. I’m thinking that your system is probably working fine – a 5kW system in Sydney (I don’t know exactly where you are so just using Syd as an example) will produce about 20kWh of energy per day. Assuming your bill was a quarterly bill and the system was installed for the full 90 or 91 days of the billing period, it would have produced about 1,800kWh (very rough figure only). If you’re self-consuming 1,000kWh, that’s a self-consumption ratio of about 55%, which is reasonable for a system of that size.

      Has there been a reduction in your bill overall (aside from what’s listed regarding solar export)? That’s where you should be seeing the savings if everything is functioning properly.

      Hope this helps! Feel free to reach out with any further questions.

  8. My daughter has a 5kw solar system. We live in Gladstone Qld. I have a 3kw system & my system produces more power than hers. Her average output for 1093 days was 9kwh. Can you suggest why this should be (we live within 4km of each other) thanks…..Bill

    1. Hi Bill,

      There are lots of possible reasons this could be happening. My first question would be about shading – is their any shading at all on your daughter’s roof throughout the day? Even partial shading can have a significant impact on solar system output (unless you’ve got microinverters).

      Do either of you have apps or some kind of monitoring apparatus for your systems?

  9. Hello,
    We have purchased a home with a Solar power System fitted to which our previous residence did not have. As this is all new to us – How do I know how many Kilowatts the solar system is on our new home and do I need to have it re-connected to be fed into the grid as i assuming that the previous owners would have had their account cancelled ???

    1. Hi Bradley,

      The best way to see if the system is working at all might be to look at the inverter (which should be at eye level somewhere on your property – looks like a box stuck to a wall with cables coming out) – hopefully it has some kind of interface on it that shows your system’s energy production.

      Alternatively, you can wait until your energy bill shows up and see if you’ve got any credits for your solar there.

      What state are you in?

  10. I have a 1.5 kW system yet on average am only getting 290-300 kWh export per 3-month period. As an example for a 92-day period, the export was 291 however if I were to base on the above average of 6.3 kWh (in Brisbane), then I should be getting about double that.

    Is there an reason fro possibly not getting as much solar as possible?

    1. Hi Kelly,

      What’s probably happening is that you’re ‘self-consuming’ most of the solar energy that your system produces – using the energy directly with your appliances. This is not a bad thing, as it’s saving you money by reducing the amount of electricity that you have to purchase from your electricity retailer. 1.5kW is relatively small, which increases the likelihood that you are indeed consuming most of the energy as it is produced. Do you have any numbers on the system’s total energy production?

      One point of possible confusion is that you only see exported solar energy (and not self-consumed solar energy) itemised on your electricity bill. It may in fact be the case that you’re exporting 300kWh per quarter and self-consuming the balance (approx 300-380kWh). The only way to tell is by knowing what your solar system produces in total on average – which would not be detailed on your electricity bill (you’d have to look at your inverter or whatever monitoring software you have, if any).

      Hope this helps!

      Also, depending on whether or not you have access to the 44c/kWh solar feed-in tariff or only the 6-8c/kWh currently on offer by most electricity retailers, you’ll want to aim to use your solar energy differently. Basically, if you have access to the 44c/kWh rate, you’ll want to export as much solar as possible to maximise savings; if you have access only to a lower rate, you’ll want to try to self-consume as much solar as possible to maximise savings.

  11. Hi there.

    We have moved into a property with 33 solar panels but I suspect they aren’t working very efficiently. They probably need a clean and service.

    What I’m hoping to find out is roughly how much energy would you expect to see 33 panels produce?

    I’m in the Blue Mountains, NSW.

    My current bill says for 99 days the 33 panels produce 143.000 – is that what you’d expect or too low?

    Thanks!

    1. Hi Emma,

      Your system is almost definitely underperforming. Without knowing the capacity of each panel (how many watts?) or the total capacity of the system (how many kilowatts), it’s hard to say exactly, but it should be around 5-8 kilowatts if it was installed within the last 5 years. Over the last 99 days you should have seen around 2,500 kilowatt-hours (kWh) of electricity produced (you’ve indicated only 143kWh).

      My first guess is that it’s a problem with shading, knowing from experience that a lot of homes in the Blue Mountains are surrounded by trees. Even partial shading is bad for solar systems with central inverters, while microniverter systems perform better in shaded conditions.)

      If shading is definitely not a problem, there could be a problem with one or a few of the panels – or possibly the inverter itself.

      The best thing to do would be to get in touch with the company who installed the system (if you have those details), or – in the case that you can’t locate them – get in touch with a solar-accredited electrician to have a look. I’m guessing that the system was installed under NSW’s generous solar feed-in tariff scheme (whose 60c/kWh payments finish at the end of this year), which means you could be missing out on some significant energy bill savings, so it could be worth paying to have it fixed if it’s not a major issue.

      Best of luck!

  12. We have a 3.5kW system, 7 panels facing east and 7 panels facing west. We are now on our second inverter and about to have it replaced again as we are not producing (apparently) any energy at all. We are being billed for every kW we use at peak rates. Our bills are roughly $800.00 per quarter and even though, we have sent energy back to the grid we are only getting $0.51 cents per kilowatt. Not sure how we are sending back to grid if we aren’t producing, but that’s what we have been told. Our energy supplier, just keeps telling us that we shouldn’t expect to save any money at all just because we have solar. We paid roughly $7,500 for our system eighteen months ago and we feel like we have just wasted our Monet rather than creating an investment.

    1. Hi Narelle,

      Sorry to hear about the problems you’re having. Just to clarify, are you getting 5.1c per kilowatt-hour (kWh) or is it 51c/kWh. I’m going to answer you based on the assumption that it’s 5.1c/kWh – which really isn’t very much at all but is unfortunately pretty standard across Australia now.

      These days, going solar is really only worthwhile if you are able to ‘self-consume’ as much of the solar energy that you use while it is being generated – this means trying to run appliances during the daylight hours. The company who sold you your system should have explained this to you from the outset – if they didn’t explain it, I would question whether they are a trustworthy company. Also, $7,500 (about $2.14 per watt) is a bit on the high end price-wise for a 3.5kW solar system, even for October 2014 (when I gather that you had your system installed).

      I’d recommend first making sure that your inverter is, in fact, malfunctioning. It’s not really clear from what you’re written if you’re certain that there is a technical problem with your inverter (how much does solar energy does the inverter say the system is producing?), or if you’re assuming that it’s not working because your electricity bills are still so high. Your electricity retailer is correct that having solar panels does not necessarily guarantee that you will save money (again, the company that installed your system should have explained this to you). If you use none or only very little of the solar energy directly, most or all of it will be sent back into the grid at very little benefit to you (the 5.1c/kWh). By contrast, if you self-consume the solar energy, you will probably save more money (whatever you pay for retail electricity).

      There are a couple of other things that I should point out:

      -If you’re on a time-of-use (TOU) electricity tariff, you might want to consider switching to a flat rate. Even with some of your panels facing west, it’s unlikely that the energy that they produce will cover all of your peak-time (and most expensive) energy usage. Instead, your solar is probably being consumed most during your less expensive off-peak and shoulder periods. Depending on what your exact rates are, you could stand to save a lot more money on a flat tariff, where you pay the same amount per kWh no matter when you purchase the electricity.

      -If you’re on a 3-phase connection, you’ll want to ensure that your inverter is either a 3-phase inverter (which is unlikely for a system as small as yours) or that it’s connected to the phase that uses the most power in your home (again, if you’re installer was really thinking in your best interest, they would have spoken with you about this). If you’re on single-phase power, on the other hand, this probably isn’t the issue that you’re having with your system.

      Hope this helps, and best of luck with your system!

  13. My xdaughter has 24 panels and her last bill was 300 odd dollars, she used hef air con for 5 days in the 3 months she only gets 6 cents per kilowatt on energy saved. So why is her electric bill so dear. She works 9 hours a day and uses the air con from 6amm to 6pm on the 5 days. What is she doing wrong.

    Jane

    1. Hi Jane,

      It’s hard to give answers without knowing more of the specifics. For example, are you talking about a quarterly or a monthly power bill? If you’re talking about a quarterly bill, then $300 really isn’t a lot to pay – especially when running AC for 12hrs/day!

      Just in case there’s some kind of misunderstanding, I should state that these days saving money with solar panels means that you must ‘self-consume’ as much of the solar energy produced as possible. In most states, a home will save in the range of 20-28c per kilowatt-hour (kWh) of energy by using their solar power as it is produced (while the sun is shining). Otherwise, the solar energy is ‘wasted’ – sent back into the grid for only 6-8c/kWh.

      What I assume is happening with your daughter is that here system is actually stopping keeping here power bill much lower than what it would be otherwise – AC is expensive to run, as it uses a lot of energy. If the installer told her that she would be able to completely eliminate her power bill, they were lying. These days, with solar feed-in tariff incentives having been closed in virtually every state, it’s basically impossible to have a $0 energy bill unless you get off the grid entirely (which is not economical for other reasons). Even if you have a grid-connected solar+battery system, you’ll still be charged fixed ‘supply’ charges which don’t go away if you consume less energy.

      Hope this helps!

  14. Im still stuffed with 18 panels 4.5 kw yet stll pay around %80 of what was my old bill.
    I need an assessment to be done. Who do i get. the installer says all is ok.

    1. Hi Rob,

      The problem may be with your electricity consumption patterns. If your solar panels are generating energy but you’re not using any appliances at home, then you’re probably not going to see the sort of electricity bill reductions that you were expecting – even if your solar system is working perfectly well, as your installer says may be the case. You need to be consuming more electricity during the daylight hours. If the installer didn’t explain this to you clearly, then they did not fully relay to educate you about how solar works in Australia these days.

  15. HI
    I have a 4.5 KW 18 panel system set up but only get a minimal amount of refund from the server.
    The sysytem takes in on average around 10 -12 kw per day. Ranges from 4 to 14.
    Im with ausnet and powershop but get stuff all rebate. Why is this

  16. Hi admin
    I have a 4.5 w solar system installed for the past 12 months I live in Healesville Victoria. I have a smart meter from SP AusNet.
    I have created a daily record sheet for solar output/ kWh & smart meter reading usage including feed in tariff, from which I can calculate the usage & cost daily. If anyone is interested they can e-mail me for the sheet at the above e-mail address

    1. Hi Frank what sort of rebate do you get. Im getting stuff all with 18 panel and a 4.5 kw system.

  17. Hi, I am doing a school solar project which is due next Friday. The project is for a Solar Installation and to make an efficient solar farm for my school. I need to convince my audience the project will be cost effective, how many solar panels I need and how much power or energy I need to supply.
    What would be the best solar system plan to use for powering a school and how would I work out the costing?

    1. Hi Liv,

      The first thing you’d need to do is figure out what your school’s daytime electricity consumption is, then size a solar system to match it. I assume you’d be mounting the system on the school’s roof?

      As for pricing, you can check out our commercial solar PV price index articles to get an idea of what different size solar systems cost.

    1. Hi junglecook,

      We wouldn’t be the best to advise on this topic, although someone else in this forum may chime in. We’d advise getting in touch with an electrician or solar installer about what your goals are, or reference the user manuals of both the panels and charge controller that you have.

      Good luck!

  18. hi!

    im nathaniel from mariano marcos memorial hospital & medical center, can you please help me for sizing the solar system for the hospital? the hospital’s monthly power consumption is 115,000 kw.. what is the size of system should be use.?

    1. Hi Nathaniel,

      It would be hard to size a system without knowing more of the details of your electricity usage, sunshine hours available where you are, and the solar PV support policies of the Philippines government. If you mean to say that your usage is 115,000kWh (not kilowatts or kW), you’re looking roughly at a 100kW system.

  19. Hi,

    Nice summary. I am a novice and would like to setup a mini solar electricity generation system in my roof. But I have no idea what all things will I be needing to do it (Exhaustive I mean). Assuming I have a 500W 24V solar panel, what else should I need to make it usable for household use – 220V AC.

    As far as I browsed, I would be needing a charge controller, battery and an inverter. So, what would be the config of these devices which would be required in my case and also are there any other things I would be needing?

    Thanks a lot for someone who takes time to reply to this.

    1. Hi Harsh,

      We’re not in the position to tell you what you’ll need if you’re planning on installing the system yourself, although it is certainly possible (especially if you happen to be an electrician). Getting a solar installation kit (with all parts included and designed for a 220V AC home) might turn out to be an easier choice than piecing a system together from individual parts.

      1. Thanks for the reply.
        I am just wondering how hard could it to be to assemble such a setup. Should just be connecting few ready-made devices properly, noe..!
        Anyways, thanks again.

  20. Hi I am answering a question for my uni assignment and its on “Is the efficiency of Solar Panels improving”?

    I need some statistical data preferably graphs that show a trend of solar panel conversion efficiencies improving over the years and predicted efficiency conversions well into the future but i’m not sure where to start with my research, any suggestion guys?

    Kind Regards

    1. Hi David,

      There have been lots of developments that promise to improve solar panel efficiency have been taking place, but it’s hard to predict which ones will be adopted first. A big factor is commercialisation–whether these technologies can be implemented economically. Conventional silicon–currently the most popular technology–might even be usurped by other materials like graphene.

      I’d recommending looking towards Bloomberg New Energy Finance (BNEF) and McKinsey for some actual past and predicted future figures.

      Good luck with your project!

  21. Hi, I have 3kW of panels and a 5kW growatt invertor. North facing at 30 degrees tilt and zero shade. I have 2 questions…. what instantaneous wattage should I get at Noon? and secondly, what total gereration on a cloud free May Autumn day? Have had issues with the unit and can’t seem to get reliable advice on what I should be getting. Thanks !!

  22. Sir. How much area is required to make around 100kwh(4*24) per day? I my area we receive sunlight for 5-6 a day.

    1. Hi Deepak. You’d need approximately 20kW of solar panels to produce 100kWh of power per day. The area will depend on the exact panels used, but assuming an average-sized 290W panel (1.954m x 0.982m) is used and the panels are laid flat, approximately 6,620 square meters of are would be required.

  23. Calculating the energy output of a solar system can be rather complex. The formulas to use are difficult for a person that has no or little knowledge of elementary physics.

    There are several sites that provide an easy way to calculate the energy output of a solar system. For example on http://www.sustainableenergyworld.eu/solar-panel-energy-output-calculator/.

    The calculator on that page first determines the maximum capacity in Watt of your solar system by asking you the number of panels and the maximum capacity of each panel. Then the revenues of the system are calculated depending on where you live. The revenue is given in kWh/year. Finally a correction is made for the actual placement of the panels depending on the irradiation factor. The irradiation is a function of both the orientation and the inclination of your solar panels. You only have to supply the orientation and inclination in degrees to finish your calculation. The calculator gives you the result in kWh/year. Furthermore the calculation method used is explained in a clear way. Worth a visit!

  24. Hi,I have had a 3kw system on a north facing roof for just a year. The panels are 12x LDK 250 D and the inverter is an Aurora 3kw. I have noticed that the peak output of the system has not exceeded 2140 w since the start of this year and was only 2150 last year. The reading on a sunny day is around the 14.5kwh mark. This would seem to indicate the system is producing approx 2/3 of its rated power. Is this reasonable or is there a possible problem I should follow up? Thanks Kurt

    1. Hi Kurt,

      With all the variables optimised, your solar PV system should operate at about 90% efficiency. A one year old system operating at 60-70% does sound like there is a problem. In an ideal word your panels will face due north and be tilted to a degree that is a little lower than the line of latitude your house lies on. You might want to check that there is nothing shading your panels (including themselves – unfortunately we have come across this from installers not on our network), if one panel is even partially shaded it will effect the output from those on the rest of the string.

      As the problem has been ongoing for a year, it might also be worthwhile getting the installer out to service the system. Issues with the wiring or the inverter would dramatically effect the reading on your meter.

      Hope you get this issue sorted soon.

  25. I have a 16 panels/3kw JSI 3000TL grid connected inverter (CHINESE MAKES ) and I have noticed that my panels are now a mixture of blue and black . This was not the case when they were installed 10-2-12. I have been experiencing larger than normal power bills of this period .My panels are on a tilt system and I live in Hallett Cove south of Adelaide and have full sun for 100% of the day What I have stated Re: the colour of the panels ,IS THIS NORMAL APPRECIATE any comments you have Regards Ray

    1. Hi Ray,

      Although you’re panels can change after they are exposed to the elements it’s not normally a huge change. Mono panels should all be uniformly dark, while poly panel will have a range in colour.

      If you’re panels started dark and have discoloured to a light blue colour this suggests that something could be very wrong. We had a visit from a premium panel manufacturer and he showed how their panels perform over time compared some of the less reputable manufacturers, the panels who’s performance decreased significantly over time had turned light blue.

      The other thing you might want to check is the inverter, generally speaking we encourage customers to go with European manufacturers because the Chinese products just aren’t up to scratch, although we’d be happy to be proved wrong.

      I would contact your installer and get them to come and check your system, if it turns out it’s an inverter issue and they offer to replace I’d recommend investigating the possibility of upgrading to a European model. SMA, Fronius and Aurora are reputable brands but you can research anything else you’re offered on the internet before going ahead.

      We hope this helps and it’s only faulty wiring not the components that are the problem!

  26. I got a 3 Kw solar system installed last month – 12 X 250W Polycrystalline LDK panels with Omniksol 3.0k TL Inverter. The inverter allows for remote monitoring via wi-fi and I’ve been watching the performance of the system for its 20 days of operation so far. All panels face West (even slightly NW) and there is no any shadow cast at any time on any of the 12 panels. The tilt is approx. 22-25 degrees. What I would like ask is whether it’s normal that the highest peak power generated so far on a really nice clear sunny day is between 1650-1700W with only 1 exception of 1980W after a period of cloud. Now I understand that I can’t expect to get 3.0Kw (as peak) since my system is facing West and I believe I automatically loose around 10-20% efficiency but what I get is actually bordering 50%. Am I right to think that there maybe something wrong (with the installation?) and what do you think the possible reason for that low peak power might be? Do you think I should contact the company which I purchased the solar system from or the subcontractor who installed it.
    Thank you very much for your support!

    1. Hi Tanya,

      I’ve just spoken with one of our team who is a qualified electrician and used to install system before moving to Solar Choice. Given the details you’ve passed on he suspects it’s an electrical issue and advises that you contact the installers to arrange for them to come and check the system. Check your warranty as you may have a clause which would cover this call out.

      If the electronics are wire correctly the other option is the inverter, Omnik Inverters are not used by any of the installers on our network and I’m not familiar with their products. I’m slightly concerned with the poor English on their website, the better quality manufacturers tend to spend the time getting the small things right. If it turns out that this is the problem I would try switching to a different manufacturer, you can research the different options online. Whirlpool forums are great for getting feedback from people who have dealt with both installers and manufacturers.

      Generally we advise that people spend some time doing their own research before signing any contracts. We do the due diligence on behalf of our customers but it’s always great for customers to go that extra mile to ensure they’re really comfortable with what they’re signing up for. Look for companies that have been around for a while are generally a good choice, a companies website is a good indication of whether they’re investing in the long haul and reviews from other customers (try getting ones in the last few months) are a good indication of performance.

      Hope this helps.

  27. Hi, I live in Punchbowl in NSW. Recently I got a 2kw Trina Solar installed along with a Delta inverter. Today the 4th of Sydney the inverter showed that it produced 13,340wh which 13kwh. Is this correct?

    1. Hi Hany,

      When we talk to customers about how much energy their solar system will produce we normally advise an average of 4kWh per kW installed. As we’re in the middle of summer with longer day light hours and the beautiful sunshine your panels will be generating for longer and at a higher intensity.

      We hope this helps

  28. I have 2kw system with 10 – 190w facing north and want to upgrade to extra 3kw with 12 – 250w facing west will SMA 5kw will work or I need another inverter.I have approved to put extra 3kw.

    1. Hi Teddy,

      From what you’re saying you currently have a 5kW inverter with 1.9kW of panels attached and want add another 3kW to this. Technically this is feasible and I know some installers, who are not on our network, actively sell larger inverters with the promise you can ‘add on’ later. The problem you do have is that ‘adding on’ is not straight forward.

      Hopefully your inverter will be a dual input inverter meaning that to can set up the 250 watt panels and plug them into this second input socket. You may need have have your cables upgraded but the installer should be able to advise you of this.

      The worst case scenario is that you have a single input inverter. This causes a problem as solar PV systems only work as well as the worst panel, so your new 250 watt panels will only function at 190 watts at best and possibly a lot lower than this depending on the age of your panels. If this is the case you have a few options: find some 190 watt panels that are as close a match as possible to your existing system; replace all the panels with 250 watt panels, or stick with your current set up. Although the second suggestion sounds a bit extreme if it dramatically reduces your consumption from the grid thew ROI may be worth it.

      Lastly please bear in mind any changes to your solar PV system may result in you loosing your current feed-in tariff, your energy provider and installer should be able to help you with this.

      We hope this helps

  29. I have a 3.5 KW Growatt inverter with one string of 8 x 190 watt panels and one string of 7 x 195 watt panels. The watts they are producing are 1440 watts for the first and 840 watts for the second string. At any time of the day the wattage difference is aprox 60% but it should be ony 10%. Please help! Thanks Thomas