How Many Solar Panels Should You Buy?

Your point about rising quickly to the inverter limit is really pertinent. In summer my6.6 kW system rises up to 5kW early and then clips off at 5kW for most of the day rather than looking like a duckbill if I only had 5kW of panels. Best I have had on a winters day was 26 kW which briefly reached 5kW at midday. Definitely a smart move!

People forget that when your system has dropped to 90% efficiency you only have to add one more panel and go for another 25 years. No wasting your installed system. So 50 year life time of free power. (except for the extra panel after 25 years)

The biggest constraint with my system design is council regulations (Tas - Kingborough). Either tilt racks or larger than a certain area of roof space occupied by panels needs a building surveyor and cert of likely compliance. About $1k added cost. Not worth it, so highest W/m2 panels are the go, resulting in a 7.6kW system. (With a special solar resistive HWS for self-consumption).

Dankie/ Thx Finn. About a month ago a heard this form an electrician. Solarpanels are very, very expencive in ZA! So a farmer in middle of the semi-desert Karoo installed about 30(?) solar panels on the farm. Some how and same were (Google Earth?) some one find out about the solar panels in this farm in the middle of nowhere. All that solar panels was stollen! It was a very very BIG finanical loss for that farmer....

Thank you ver informative.

Im in Perth wa. So the inverter limit with Western Power is 5kw to qualify for the DNSP this equates to 6.6kws of panels ,right? I want to install a complete new system with a 10kw battery. But I have read somewhere that if I install a 5kw hybrid inverter I can over size panels I installed a bit more than 6.6kw to ensure the battery gets charged as much as possible throughout the year. Can you please tell me if this correct and what is the max kw of panels I can put on my roof here in Perth?

We just put in a premium LG system with battery and black Neon panels (regional Victoria). Agent wanted to do everything with the stupid outdated satellite photo instead of a site visit. They are all the same. 🙄 We ended up with a battery that is smaller than we actually need, the sales person was not really up to speed, the installers were good thankfully on our small very high pitched roof. We are pumping out way more than anyone expected especially with 6 of 14 panels south facing get sun until sunset! unlike the north and eastern panels. We worth doing with a battery, was tired of 12 blackouts in 12 months, some for many hours.

I have a complicated roof with solar hot water already taking up space, plus some shading. I've always thought solar PV would be uneconomical but with the higher capacity panels and micro-inverters it may just be worth it. Time to do some more research I think

I agree

If you have batteries, the more panels you have, the less batteries you need. Re the DNSP, just buy an inverter that allows you to limit the export (I know that Selectronic ones do, I imagine most do)

Forget batteries it is much cheaper to install a second system and sell a large amount of electricity to the grid and pull a little expensive power at night. Ezi pezi. When you buy a new Electric Vehicle in the near future, it comes with a huge battery for free. The vehicle will back you up at night at no cost.

One thing that isn’t mentioned here and rarely makes a video but is very important. Panel production decreases fairly significantly as they get dirty. So 6kw of power will certainly degrade over time unless you clean them. Having extra panels will significant help you stay in the ideal range much longer between cleaning. And cleaning cost is typically higher to roll the truck than a function of the number of panels to clean.

What more savings is what you paid for power and what you don't have to pay for power when you have solar and not what you make from solar because that is profits of more than your house uses. Or in this case I paid 135 dollars a month and now I pay 35 dollars a month. That is 1200 dollars a year you save. And that is more money for me to put in to more solar panels. And when I start selling it to the power company that money is profits and of course I will put that in to more solar panels until I have no more place to put more solar panels.

you can export as much as you want, you only get paid for 5kw

@3:40 5kW x 1.33 = 6.65kW

I wonder why solar is so cheap in Australia? I just got a quote for $18,000 for a 3.6kW system. That would be $27,000 in AUD.

Surely one’s budget .

I will get as many as I can get in my yard and on the side of my house and then get as many as it will cover my house and then I will get more.

Until your roof can't fit anymore

When are the panel manufacturers going to get a brain and design a integrated gutter system so these provide a 30 year leakproof roof. Add space above flat roof to make a Patio as well, and reduce AC use as sun is never hitting the roof.