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Learn about the typical solar investment returns for each state capital in Australia in 2019.

A year and a month ago, I wrote an article about the simple payback time of rooftop solar, that is, the time it takes for the cost of solar energy savings to be equal to the system cost. In most Australian capitals, this takes about 5 years or less, which means rooftop photovoltaics are one of the best investments that households can make.

I did the same thing again—except for the difference—and observed the simple payback time of a 30% larger 6.5 kW solar system. The good news is that the payback period is now faster due to the drop in the cost of high-quality solar installations. They are under 6 years old in every capital, and most of them are under 5 years old.

Update at 1:57 pm on June 13th: I initially ignored that Tasmanians can now get a feed-in tariff of 13.5 cents from 1st Energy. I have updated this article to include it.

The simple return is that the time required to save electricity is equal to the cost of installing a solar system. It does not consider the following costs:

But this is not a big deal, because its shortcomings are not enough to diminish its huge advantages that are very easy to understand. In addition, its shortcomings are not the main problem because:

Therefore, when the simple payback period is about 5 years or less, it should be very close to the result of a more comprehensive inspection of the payback time.

In order to determine the simple payback time, I need to make the following assumptions:

Last year I studied the simple payback time of a 5 kW solar system, but now I am studying 6.5 kW. The reason for the increase in size was not because I increased the weight, I am now trying to hide it by associating it with a larger solar system. 1 This is because most households have single-phase power supplies, and the maximum capacity they can easily install is usually 6.66 kW. Because rooftop solar is a good investment, I think people who use 6.66 kilowatts as an effective limit should get as close as possible to it. However, if you can install more effortlessly, I sincerely recommend that you do it.

I assume that a 6.5 kW system can be installed for $6,500. This is 30% lower than the figure I used last year per kilowatt. Although it may be more cost-effective to buy a larger system, the main reason I lowered the price to $1,000 per kilowatt is that I now believe-through reasonable research-that people in densely populated areas can find good quality at this price installer. Although this will not buy the best solar hardware, it will pay for a reliable system and fair and reasonable after-sales service if needed. 2

The cost of solar energy is not uniform across the country, but I will use the same price for all capitals to easily compare their payback times. The most expensive capitals are Hobart and Darwin because of the long distance, the small market size, and-in Darwin's case-everything needs to be crushed so that the hurricane does not involve your solar power system in Allah. Frahai.

Melbourne is a special case because Victoria has a tax rebate that reduces the cost of solar energy by up to $2,225 for eligible households. This will start again on July 1, and the news on the street is that it is the same amount. Regardless of whether there is a $2,250 rebate, I will give a simple Melbourne investment recovery time. 3

In order to calculate the simple payback time of solar energy for a typical Australian home, we will determine how much electricity the typical home uses. It varies from capital to capital, but I will use the figure of 5,000 kWh per year for all locations. This is close to the average level used by Australian households without natural gas.

For the annual solar output of 6.5 kilowatts in each capital, I used 95% of the north-facing panel data given to me by the PVWatts site:

I only used 95% of the PVWatts figure because most households will not be able to face their solar panels in the best direction and it allows the output to drop slightly over time.

Households usually consume part of the solar energy they generate and send the rest to the grid to charge feed-in tariffs. Since the grid electricity cost is higher than the feed-in tariff, a higher self-consumption rate will result in a faster return time.

Smaller solar power systems may result in higher self-consumption and faster return on investment time, but will result in less total savings in electricity bills. Therefore, shortening the payback period by reducing the size of the system is usually a wrong economic practice, making you want to install a larger system from the start.

Households use differently, but on average, households with a 6.5-kilowatt solar system use about 20% of their solar power generation, so I will use that number.

Calculate how much the annual electricity bill can be reduced by 6.5 kilowatts of solar photovoltaic energy. It is necessary to subtract the electricity bill for installing solar panels from the situation where solar panels are not installed. I did a search and used the most cost-effective standard tariff 4 plan for the two situations in each capital, and put them in the table below along with the annual savings from installing solar panels:

Or if your vision is reduced:

In Darwin, Hobart and Perth, electricity prices are fixed, but in other capitals, there are retailer options and a wide range of electricity plans to choose from. There may be better plans than I have used, but they are unlikely to make a big difference. You can also bargain with electricity retailers, so you can get better deals this way, but the closer they get to being the best option, the less likely they are to compromise on prices.

As you can see in the table above, in Adelaide, Brisbane, Canberra and Darwin, the annual electricity bill for solar panels is creditable. This means that in more than a year, households will receive more money from electricity retailers than they paid. Darwin did a particularly good job because their feed-in tariff is the highest in Australia and equal to the cost of grid electricity. Although the electricity bills in Sydney and Melbourne are not part of the credit line, they are almost zero. This means that in most capitals, a 6.5 kW solar system can reduce the annual electricity bill of a typical household to near or below zero.

This graph shows the feed-in tariff received by each capital in cents per kilowatt hour:

The figure below shows the simple payback time of 6.5 kilowatts of solar energy in the Australian capital:

Due to Australia's highest solar feed-in tariff, Darwin has the fastest payback period. The second fastest is Melbourne, at 3.2 years. This is indicated by the light blue part and assumes that the Victorian Solar House Package reduces solar energy costs by US$2,225. If this is not included, the simple payback period for Melbourne is 5 years. Due to high feed-in tariffs and high electricity prices, Adelaide ranks third.

Perth is the city with the longest payback period on the mainland5, even though it is the sunniest capital because of its lowest on-grid electricity price. Hobart is the capital with the least sunshine, but it performs much better than Perth due to higher feed-in tariffs.

I used 20% of the figure for solar self-consumption. Although retirees and others who are usually at home during the day usually use more than this, some people who are usually away from home all day may wonder whether solar energy is a good investment for them. Well, this is no problem, I have solved the problem for you, and I made a chart that shows the simple payback time of each capital if you somehow manage to not use solar energy at all.

This is almost impossible because electrical appliances such as refrigerators and freezers should still consume electricity even if no one is at home every hour of every day of the week. But to show the worst-case scenario, here are the results:

As you can see, zero self-consumption has not had a huge impact in most capitals. With the exception of Perth, solar energy still pays for itself quickly. Because their feed-in tariffs are so low, zero self-consumption makes a big difference. If you want to get a good return on investment time there, I suggest ensuring that you have a reasonable self-consumption rate. But everywhere else, I would definitely say that solar energy is still a good deal, even with zero self-consumption.

Electricity prices and feed-in tariffs may fall in the future and extend the simple payback period of solar systems currently installed. But this is not enough to make rooftop solar a bad investment.

As the cost of solar energy drops even lower, the simple payback period will be further improved. But I'm sure that waiting will not save you more money than buying solar panels now and immediately reducing electricity bills.

Ronald Brakels was born in Toowoomba many years ago. When his township collected a collection and sent him to Japan, he became famous internationally for the first time. This was the furthest place they could manage with the funds raised. When the local mayor greeted him at the airport and explained that it was too dangerous for him to return to Toowoomba due to climate change and mutations attacking goats. After returning to Australia, he developed a keen interest in environmental issues. Ronald then moved to a property in Adelaide Hills, where he now lives with his horse Tonto 23.

We now have a second retailer in Hobart Ronald (1st Energy). As far as I know, the differences are negligible, but can you include them in future calculations so that we can understand alternatives.

I completely ignore that Tasmania now has a second retailer that has higher feed-in tariffs. I forgot that. I have updated this article to include it. Thank you for pointing it out.

Thank you-I have already made a change in the end!

Hi Ronald, your Sydney 20c FIT is hard to find. I got it through AGL, but the only way In found it was through an article you wrote about it last year. Another area that is confusing is that different retailers offer different FITS. AGL has a simple no-discount plan that reduces the cost of electricity supply, but only pays 11.1c FIT. Honestly, it is difficult to determine which plan is the best.

100% agree. This is why we have this tool on our website:

https://www.solarquotes.com.au/energy/

This will work for you! It should be noted that you should double check your qualifications with the retailer before registering-because they may have fine print: maximum kWh or maximum system size, the tool does not take these into account.

(Also only flat rate tariff)

Hi, Finn AGL in New South Wales limits it to 10Kw inverters. I have 3 phases and 3 independent systems with a power of 9.5 kW.

Hi Ronald, informative article as usual-thank you very much for doing this. In order for the payback period to be useful, must you definitely consider the cost of capital? Assuming that regular payments to power suppliers are counterfactual, a reasonable estimate would be the interest (or opportunity cost) of half of the capital for the entire period. Given that the current cost of capital is actually about 5%, the capital cost of about 2.5% should really be included in the payback period calculation. Phil

To be precise, the payback period needs to consider the cost of capital. But I just completed the simple payback period because it is easy to understand. Everyone gets it and can use it to help themselves decide whether solar energy is cost-effective for them. If people are interested, I can calculate the complicated payback time, but this will be a more complicated article.

Great article, even better than I thought. I didn't realize that so many people would be credited in a year.

However, you said "I consume about 20% of solar power generation". This is extremely pessimistic. According to our data on more than 11,000 systems of this size, the average self-consumption is 37% (ranging from less than 10% to more than 80%).

Therefore, for most people, the return is even better.

It almost makes you think that installing solar energy on the roof is a good idea, especially if you want to avoid your children hating you for letting the earth fall into climate chaos

Is it suitable for a system of around 6.5 kilowatts? My figure is that for a typical family, a system of this size has about 20% of self-consumption.

Does your modeling assume that the nominal system has: – 6.5 kW solar photovoltaic panel array; – The array faces true north and is unobstructed; – The array is at the optimal height to suit the specific site latitude; – Coupled to single-phase grid connection 5.0 kW inverter; – connected to the net metering grid; – including STC rebate?

Do you use the numbers from the STC calculator in your modeling? https://www.solarquotes.com.au/tools/stc_calculator/

Is there a 6.5 kW rated inverter, or a 6.5 kW solar photovoltaic array system is usually used in combination with a 5.0 kW rated inverter?

If the output capacity of the inverter is the same as the capacity of the solar photovoltaic array, will there be a big difference in the payback time? Worse or better?

You said: "As the cost of solar energy drops, the simple payback period will be further improved. But I'm sure that waiting will not save you more money than buying solar panels now and immediately reducing electricity bills. "

I agree. IMO, any owner of a detached house with suitable, barrier-free roof space and no solar photovoltaic system has missed the opportunity to significantly reduce energy costs.

I use the default value of PVWatts just to make it easier for anyone to copy me. The losses they have considered are:

2% Panel mismatch loss 2% Dirt loss 3% Shadow loss (this means slight shading) 2% Wiring loss 0.5% Connection loss 1.5% LID loss 1% loss (There is a difference between the rated equipment and the equipment you get.) 3% availability loss (for example, grid overvoltage event.)

They also assumed a slope of 20 degrees, which is an integer between the most common roof slopes in Australia.

I did not adjust the inverter to photovoltaic ratio. This will reduce the output by 1-2%, but PVWatts still uses 96% inverter efficiency, which is about 1% lower than today's efficiency. I used 95% of the north-facing panels provided by PVWatts to solve other losses, such as sub-optimal panel positioning. and many more.

Assuming that the grid connection is normal, the price I use includes STC, which reduces the cost of solar energy.

The 6.5 kW system in my example has a 6.5 kW solar panel and a 5 kW inverter. A 5 kW inverter is the maximum power allowed to be installed in many single-phase power supply households.

I don't know which inverters are exactly 6.5 kilowatts, but if you use one of them, the profit will be small and the investment recovery time may be reduced by 1%.

5kW is not the maximum limit for single phase. I have obtained a 10.1kW inverter capacity, allowing the use of 11.3kW panels, provided that I have installed a 5kW outlet limiter. But the big deal... Anyway, I don't output 5kW most of the time.

Inverter 1: 1.5kW (8 years old) Inverter 2: 3.6kW (6 years old) Inverter 3: 5kW (6 months) 45 panels + Powerwall 2 5kW

Therefore, the total inverter capacity of a single phase = 15.1kW.

Fortunately, not everyone is facing the 5 kW solar inverter limit, but quite a few people are facing it. There are many ways to solve it, but these methods may depend on the location.

For people who are not at home all day (in Perth), the logical consequence of low electricity bills is to install batteries so that they can use some of the solar energy after sunset? What else can you do with off-grid systems (not including the cost of connecting to the grid for more than $30,000) Thank you Regina

It should not be that complicated to exercise...

Forget about depositing the money in the bank for a while... Given that most people have less than 2% interest, this is a useless exercise. Second, when the money is in the bank, you cannot do anything with it. Therefore, this is a sitting duck, which is of no use to anyone except the bank.

Using the PVWatts site as a person's location, you can get an estimated annual solar output.

There are only three results:-

1. To make matters worse, export all solar energy output for feed-in tariff. Multiply FiT by the estimated annual production to calculate the maximum possible FiT credit obtained. 2. In the best case, one person consumes all solar energy for his own use. Multiply this by a person's "normal" energy rate to get the maximum self-use value. 3. For most people, it is between 1 and 2.

Therefore, for a 5kW 20-degree tilting system charged at 11.1c FiT and 28c energy rates in Sydney, it is estimated that the annual solar power generation is about 6900kWh.

Therefore, it will be:- 1. 100% of exports may receive a FiT credit of US$765. 2. The self-consumed electricity worth 1932 US dollars is used for 100% solar energy self-consumption 3. 765 US dollars to 1932 US dollars of income, if they do not export 100% or 100% self-consumption, they may get value (so you can immediately Seeing that it must be self-consumed as much as possible, because its value is more than 2.5 times).

Approximately need:-1. Only 100% export = 3500 USD 5kW system investment payback period is 4.57 years 2. Only 100% self-use = 3500 USD 5kW system investment payback period is 1.81 years 3. Approximately between 1.81 and 4.57 years For many people, a mix of self-use and FiT credit.

It's not difficult to exercise. I don’t know why people complicate this process. In fact, there are only two figures to be calculated-either 100% export in full, or 100% self-consumption. For most people, calculating the worst and best case will be a number somewhere in between. The most likely is the 50% feed-in tariff-50% for self-use-so the return on investment on a 5kW solar system in Sydney is about 3.2 years 50/50.

Of course, for someone like me on ToU, some complexity will come into play. But because solar energy rarely plays a role during off-peak periods. I just averaged the peak/acromial period because most solar production occurs during the peak period. So even if I only use the shoulder rate, at least this will cover the worse shoulders and peak periods.

But in any case, if there is no Solar, most people would not use ToU. Endeavor Energy reports that only 0.01% of residential customers use ToU (approximately 1,000 residential customers). Therefore, using the standard retail rate at any time will be a safe number that can be used to calculate the potential value of self-use.

The benefit of ToU is that it eliminates most of the acromion/peak usage, while at the same time getting off-peak rates for the entire house in the evenings and weekends/public holidays. So, this is a win-win situation. Don't confuse off-peak periods with controlled loads-these are two very different things.

We paid 4k to a low-end retailer, installed nearly 6kw on our roof, and used rebates for 2 years of investment recovery in Melbourne. Then our electricity retailer charged us a pfit electricity price of 66.6 per kWh, and the system revenue dropped to about 7 months. I kind of hope that id now pays for a better system. With these ROIs, I could easily afford LG panels and micro inverters.

Everything is fine, provided that you do not move for 6 years, otherwise you will have to start again.

Solar energy systems will increase the selling price of your home. Even if it only increases your payment by half, you will still be far ahead.

Darwin’s 6500W system costs US$10,000 instead of US$6,500.

Where did you get Adelaide's 22-cent tarrif feed. ? The best feed for shopping in tarrif is 16.3 cents!

Go to our power plan comparison tool:

https://www.solarquotes.com.au/energy/

Enter your zip code and click "Compare Power Plans", then click "Sort by Feed-in Tariff (Highest to Low)". Amaysim will appear at the top with a feed-in tariff of 22 cents. Other retailers with high feed-in tariffs include Click Energy (22 cents) and AGL (20 cents).

I can make suggestions for this tool to increase its appeal to end users!

Given that each family's consumption is unique, most of us visit SolarQuotes to have a good understanding of the daily consumption that we reprimand.

Maybe add the sum of daily average usage in increments of 5kwh (5 to 50kw). Add the size of the photovoltaic system (1.5 to 15) and the nearest city. If you have time. Even add the percentage of self-consumption (generally the default is 20%)

That would be great! ! !

Yes, there are 6 people in my family

Yes, but Amaysims is expensive to use. The energy locals you use for billing numbers only provide 6c suitable. They all seem to be reducing the minimum suitable for new customers. I am with Origin, his price is suitable for consumption, but it provides 6c fit. Still waiting for my installation, but shop around, Adelaide's return will be longer than your estimate. Your estimate should be based on using the same supplier for both numbers, because you cannot use different suppliers for supply and feedback.

Don't worry, I use the same supplier for supply and feedback. I just used different retail plans for homes without solar energy and homes with solar energy, because families without solar energy obviously do not need a good feed-in tariff.

They are losing weight fast. When I got the installation quote, it was 20c, then 11c, and now it is 6c. That is Origin SA, but you can safely assume that they will all start to decline or charge more consumption/supply fees. Still thinking that it is worthwhile for us, we are installing a larger system, despite having a blocked feed to comply, to ensure decent power generation in winter. We don't have gasoline most of the time. It will be interesting to see our first bill after installation.

Residents of high-rise apartments in Sydney? – Understandably, the installation of rooftop solar panels is impossible.

Considering a nearby solar park? – Small centralized power transmission.

Jump to any German solar site. Most of them have solar installations, you can hang them on the balcony railings, and then plug them directly into the power supply of your installation.

I don't know if there is any in Australia.

I saw them about 8 years ago.

The FIT of 1st energy is 5c more than Aurora by one kilowatt-hour, and they also made a usage fee. I changed as soon as they entered Tassie, and I am glad I did! Let us hope that more retailers will also come to Tassie!

As far as I know, you don't know anything about the aging degradation of solar panel efficiency. Have you specified a life test cycle for different brands and types of solar panels. Nothing can maintain 100% efficiency indefinitely, and nothing can last forever. IMHO, if you want to do real ROI calculations like a TV or washing machine or any other electrical hardware, you must consider the initial cost, maintenance, and efficiency loss due to aging and the entire life cycle when making a cash investment. In addition, if a household’s usage is less than a certain annual dollar value...My cost is about $1,200, then the installation cost of 6.5Kw is $18,000, as I quoted, even if the subsidy is taken into account It also means that the return on investment is not that attractive in my estimation. So solar energy is not for everyone, unless I would say it is free.

This topic-very good-and solar 101 "#3 How many panels should you buy?" Assume that the optimal scale system is a system with 6.6 kW panels and 5 kW inverters in order to recover the investment at the earliest. For those with larger, less complex roofs, another option is to choose a larger system, such as a system with a 36 275 watt panel with 9.9 kW and an 8.1 kW inverter, which is still Single-phase power connection, but feed-in (FI) is limited to 5 kW per hour. This is possible in Queensland. For the purchaser, the additional cost of a larger system may be only $1,750 higher than the assumed cost of $6,500 above. For a 6.6 kilowatt solar home that consumes 12 kilowatts per day, half of it is during the day, which is equivalent to 2190 kilowatts per year. This amount needs to be offset from the 9,383 kWh generated each year, leaving 7,193 kW for feed-in tariff (FIT). Assuming an average of 8 hours of power generation per day, FI will be 2.46kW hourly income and FIT will be 11c/kW, which is US$791 per year to offset the US$591 of 6kW overnight grid provided by 27c/kW. This means that the revenue of $791 plus halving the cost of the grid is positive. But the FIT rate is still important, so if you can even get 22c/kW in two years, your annual income will become $1,582. Ah... I have Fin's 6.6kW panel/5 kW inverter, but only since September last year. Assuming that the annual FI is 7,193 kW, and 8 hours a day, the 5 kW inverter returns to the grid an average FI of 2.46 kW per hour. For a 9.90 kW system, it will generate 1.5 times 9,383 kWh or 14,075 kW per year. Subtracting personal consumption of 6 kilowatts per day or 2,190 kilowatts per year, leaves 11,885 kilowatts for FI each year. Assuming again 8 hours a day, this is equivalent to 4.07 kilowatts per hour, which is still below the cutoff point of 5 kilowatt hours. Under the FIT of 11 cents/kWh, the annual income becomes US$1,307, which is 1.65 times the US$791 before the standard system. The additional benefit comes from a cost increase of US$1,750 over the standard cost of US$6,500. If you can get 22c/kWh, you will really consume your investment costs. I appreciate the need for a large and simple roof structure, and there is no doubt that the 5 kW limit will reduce some peak power generation (by the way, what happens to the excess power?).

However, based on these assumptions and realistic forecasts, the 9.9 kW panel/8.1 kW inverter solar system seems to be the best choice for Queensland.

If the greater minds behave differently, it would be very happy.

If the inverter has a rated power of 5kW and is equipped with a 6.6kW panel ("33% overclocking"), what will happen to the excess power?

Nothing, no excess power... The inverter will change its MPPT algorithm to reduce the efficiency of the panel to a lower point, so that it will only produce acceptable values ​​for the inverter and will continuously adjust itself. Therefore, when the sun moves and the inverter's MPPT tracks the panel's power generation, it will adjust accordingly. Sometimes this is called editing, but it is technically incorrect. Clipping occurs on the voltage regulator (usually dissipated in the form of heat, which is a waste by-product).

Therefore, this is not the case where the excess power disappears, but the inverter changes the V/I curve of the panel to make the panel behave differently to match the inverter's maximum power input (on the DC side). The inverter does not dump excess power somewhere, nor does it dump excess AC power to keep the rated power within the limit.

But this is a good thing, because it means that when there is insufficient light/early morning/evening solar power, at the rated inverter wattage, you have 33% of the panel generating power, so you get more energy production. The potential additional energy loss mainly occurs at noon in summer. But it doesn't matter, there are only about 4 months in the year, and the rest of the year will be used to make up for the summer losses by gaining more solar production in other months.

For example, a 5kW inverter and a 5kW panel may generate about 3kW in the morning

But a 6.6kW 5kW inverter in the morning may produce about 4kW, so you can get an extra 1kW

But in summer, due to the high temperature, you will lose about 15-20%, so the additional rated power of the panel offsets this loss.

For every 1C increase, the output of the panel will decrease by 0.5%. Therefore, by overestimating the power of the panel, it can make up for the loss caused by heat during the high temperature in summer. Therefore, you can effectively maximize the inverter rating without losing too much panel power generation in hot summer conditions.

Overestimated panels are just "imitating" the effects of using solar trackers and are more cost-effective.

The solar tracker will achieve approximately 20% additional energy harvesting through single-axis tracking, and an increase of 25% if dual-axis tracking is used. But solar trackers are expensive. Therefore, it is easier to overestimate the panel by 33%. Their only advantage is actually to save space by reducing the number of panels required. If you have a lot of roof space, just use more panels to offset the difference.

In my case, my panels face east and west, so I automatically lose about 16% of solar production. By using a 33% larger panel, it overcomes this directional loss, and the inverter has less "clipping", just like I have a complete 5kW system facing north. When determining the optimal size and cost, everything has to do with the angle-latitude, inclination and direction.

Therefore, the "excess" power will not disappear due to overproduction. The inverter only uses MPPT to change the V/I curve of the panel to change the power output to match its maximum input DC rating.

I question your results in Melbourne, because firstly they don’t seem to reflect the increasing use of fixed supply charges by utilities, which have gradually risen in recent years. E.g. Half of my $150/quarter electronic bill is a fixed fee that I cannot save. Second, you call Amaysim a solar electronics supplier for $10! pa, but their website today tells me that they don't have solar plans yet. At least not in my area, Rosebud in the metropolitan area.

Are you assuming a low-star old house? Mine is 6 stars, using LED etc. and wood heating, the electricity bill is only 700 US dollars pa, mainly in summer, because I use wood heating.

I'm sorry to hear that Amaysim is not available where you are. My annual electricity consumption figure of 5000 kWh should be close to the average household electricity consumption. The average household size is 2.6 people. According to the government's Energy Made Easy benchmark site, the electricity consumption of a 2-person household in Melbourne is 4,526 kWh, and that of a 3-person household is 5,262 kWh. Of course, it is possible to do much better than average.

The article mentioned the 6.5kW system (panel capacity), as well as the single-phase connection limit of the 5kW inverter (well, it applies here anyway), and the 6.5kW inverter with restricted specifications such as Goodwe GW5000D-NS DC power, I want to know, when the DC power input of such an inverter is greater than the output capacity of the inverter (5kW in this case), will the inverter handle the excess power (I assume it is indeed not Simply handle it and output additional power), the excess power entering the inverter or facing the inverter is harmful to the inverter under any circumstances, thereby causing any damage to the inverter or shortening its life, Or anything similar.

This article (and all the other return calculators I've seen online) doesn't seem to take into account the fact that most retailers offer "pay on time" discounts for non-solar products. Mine is 25% AGL. Solar plans don't offer this kind of discount, or even if they do, it won't help when your bill is close to zero or credit. Therefore, it is incorrect to assume that your usage and daily expenses are the same before and after the installation of solar energy. For example, if I install a 6.6kW system in Brisbane and have 50% self-consumption, most calculators tell me that my payback period is about 3 years. I calculate it is closer to 4 years. Even from a monetary point of view, this is still a worthwhile investment, but people should be aware of it.

"Smaller solar power systems will lead to higher self-consumption and faster payback time, but will result in less total electricity bill savings. Therefore, it is usually a wrong economic practice to shorten the payback period by reducing the size of the system. , Making you want to install a larger system from the start."

Does this mean that even if the amortized installation takes longer, it will generate greater cumulative savings for smaller installations on the same timeline?

Thank you, and sorry for Google. His native language is English. Greetings from Spain

I would say this: a person has 10,000 US dollars, their investment options are...

1. Deposit money in the bank at an interest rate of 1%. 2. Pay off the housing loan with 3% interest. 3. Investing in a large-scale solar system worth US$10,000 can provide a 7% return. 4. Invest in a small solar system worth US$3,000, which is a quarter of a large solar system and can provide a 10% return.

The return on small solar systems is even higher, with 10% of $3,000 being only $300. But 7% of US$10,000 is US$700. Therefore, it would be better for families to obtain large-scale solar systems. If they want, they can use the money they save to repay their home loans, which is the next best investment option after solar energy.

So the system with the highest return is not necessarily the best investment. In addition, a larger system will provide greater environmental benefits, so this is a victory for the homeowner and a victory for the world.

Please keep the SolarQuotes blog constructive and useful through the following 4 rules:

1. Preferred real name-you should be happy to add your name to your comment. 2. Put down the weapon. 3. Assume positive intentions. 4. If you are in the solar industry-try to understand the truth instead of selling. 5. Please keep the theme.

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