Just now, Scorp007 said:

Not to sure drawing 400W for about 14hrs as well as the evening cooking having only 1 battery if the battery is a 5 kWh. (not specified) 

The 2nd year with 2 batteries will be OK as more day time generation can be stored. 

Its a Greenrich WM5000, we use the airfryer the most, stove is Gas and oven never used. Coffee and tea is on gas. My plan is to get another battery, but i want to get the panels sized to charge both batteries and give me usable power throughout the day.

To be honest yes your demand is on the low side, and yes there will be day's you are not going to use what your solar array is going to produce, but then you will have day's during rainy season you are dipping into the battery. If you have the means($$) of installing 12 panels i would go for it, it will set you up for future expansion on the demand side. 2 batteries(10kwh) and 12 x 550w panels will take you a long way.

10 hours ago, TaliaB said:

Yes. There is actually good production West. If you compared West to East very little difference only difference peak production at different times of the day. 

This one I partially dodged as I have never looked at comparing this. 

What a eye opener when I explored it. Panels with no shade on a flat roof (5 deg) yields more than east - west at a 24 degree looking at the year total yield. 

Hope to learn from other members calculations. 

13 minutes ago, Scorp007 said:

This one I partially dodged as I have never looked at comparing this. 

What a eye opener when I explored it. Panels with no shade on a flat roof (5 deg) yields more than east - west at a 24 degree looking at the year total yield. 

Hope to learn from other members calculations. 

Wait....so flat roof with no shade is good? 

10 minutes ago, Scorp007 said:

This one I partially dodged as I have never looked at comparing this. 

What a eye opener when I explored it. Panels with no shade on a flat roof (5 deg) yields more than east - west at a 24 degree looking at the year total yield. 

Hope to learn from other members calculations. 

Some info on tilt or inclination calculation the quick method and the correct way.

Quick and easy but less effective.

Take your latitude and add 15 degrees for the winter, or subtract 15 degrees for the summer. For example: if your latitude is 40 degrees, the angle you want to tilt your panels in the winter is: 40 + 15 = 55 degrees.

In the summer, it would be: 40 - 15 = 25 degrees.

The correct way to calculate tilt.

Winter.

In the winter months, when there's less sun, take your latitude, multiply it by 0.9, and then add 29 degrees.

For example: if your latitude is 40 degrees, the angle you want to tilt your panels in the winter is: (40 x 0.9) + 29 = 65 degrees.

This is about 10 degrees steeper than the "quick and easy" way! It's also more effective, because you want your panels to be directly facing the sun at mid-day during those short winter days.

Summer.

Take your latitude, multiply it by 0.9, and subtract 23.5 degrees.

For example: if your latitude is 40 degrees, your panels should be tilted at: (40 x 0.9) - 23.5 = 12.5 degrees.

 

5 minutes ago, TaliaB said:

Some info on tilt or inclination calculation the quick method and the correct way.

Quick and easy but less effective.

Take your latitude and add 15 degrees for the winter, or subtract 15 degrees for the summer. For example: if your latitude is 40 degrees, the angle you want to tilt your panels in the winter is: 40 + 15 = 55 degrees.

In the summer, it would be: 40 - 15 = 25 degrees.

The correct way to calculate tilt.

Winter.

In the winter months, when there's less sun, take your latitude, multiply it by 0.9, and then add 29 degrees.

For example: if your latitude is 40 degrees, the angle you want to tilt your panels in the winter is: (40 x 0.9) + 29 = 65 degrees.

This is about 10 degrees steeper than the "quick and easy" way! It's also more effective, because you want your panels to be directly facing the sun at mid-day during those short winter days.

Summer.

Take your latitude, multiply it by 0.9, and subtract 23.5 degrees.

For example: if your latitude is 40 degrees, your panels should be tilted at: (40 x 0.9) - 23.5 = 12.5 degrees.

 

Yeah but then wouldn't you need some sort of jig that you can adjust for each season... my roof is a low incline... 20 - 25degrees if that. 

13 minutes ago, NadaCT said:

Yeah but then wouldn't you need some sort of jig that you can adjust for each season... my roof is a low incline... 20 - 25degrees if that. 

Yes for sure it is the principle that 2-axis solar trackers work, but for our stationary roofs we get the average of above calculations between winter and summer. Not much you can do about standard roof pitch so we live with it.

Edited February 7, 20242 yr by TaliaB

31 minutes ago, NadaCT said:

Yeah but then wouldn't you need some sort of jig that you can adjust for each season... my roof is a low incline... 20 - 25degrees if that. 

I just tried to be a bit practical as perhaps 80% or more of strings are used. Your 20-25 is in line with my estimate and that's why I used 24 in my example. 

Yes flat far exceeds E-W on my calculator. Also unlike the previous post my E shows a much higher yield than the hot W and again with a guess in Gauteng we have more clouds in the afternoon than morning. 

People should really put their location in their profile so helpers can make an informed reply.

We don't need your home address.

9 minutes ago, Virwat said:

People should really put their location in their profile so helpers can make an informed reply.

We don't need your home address.

Yes even just a town/city or any landmark one can Google. 

16 minutes ago, Scorp007 said:

Yes even just a town/city or any landmark one can Google. 

Monte Vista, Cape Town

28 minutes ago, Virwat said:

People should really put their location in their profile so helpers can make an informed reply.

We don't need your home address.

Noted. Thanks for the feedback... i live in Cape Town, Monte Vista.