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My understanding is as follows, but I am no expert.

Assuming no shading, you generate the maximum amount of solar power when the panels are facing where the sun is at midday, which will be generally be to the geographic north.

Household power consumption during daylight hours, particularly for working families with school going children, is generally at its highest in the mornings and in the early evenings. The mornings due to cooking breakfasts, showering (for electric water heaters) etc. and in the early evenings due to cooking dinners, maybe TV watching and in particular air conditioning usage on hot days. Air conditioning usage tends to make the early evenings more energy dependent than mornings. Middle of the day usage is low due to parents working and kids at school.

About a decade or more ago, when many people were on very generous feed-in tariffs that were greater than the cost of buying power, it made sense to have the panels orientated to the north. The more power you could feed to the grid the better as you get more for your power that way than you would save in not paying for grid power.

When the generous feed in tariffs ended, the equation changed. Here in WA the feed-in tariff is only a fraction of the cost charged by the energy suppliers. That means it is better to use your own produced power as much as possible in preference to taking power from the grid. So north facing panels mean that your need for power is at its lowest when you are producing it at the maximum and your need for power is highest when you are producing the least. So an east or west or both direction solution can actually be the cheapest solution overall. You still do not produce as much power as when your panels are facing north, but the lesser amount being produced is more effective at keeping costs lowest overall.

Obviously there are lots of provisos that go with the above. Usage of smart tariff meters, being a non-typical household, having smart appliances that can be time controlled, use of battery storage etc. all will have an impact on what is the best orientation.

<blockquote data-quote="bellenuit" data-source="post: 1141812" data-attributes="member: 20825">My understanding is as follows, but I am no expert.Assuming no shading, you generate the maximum amount of solar power when the panels are facing where the sun is at midday, which will be generally be to the geographic north.Household power consumption during daylight hours, particularly for working families with school going children, is generally at its highest in the mornings and in the early evenings. The mornings due to cooking breakfasts, showering (for electric water heaters) etc. and in the early evenings due to cooking dinners, maybe TV watching and in particular air conditioning usage on hot days. Air conditioning usage tends to make the early evenings more energy dependent than mornings. Middle of the day usage is low due to parents working and kids at school.About a decade or more ago, when many people were on very generous feed-in tariffs that were greater than the cost of buying power, it made sense to have the panels orientated to the north. The more power you could feed to the grid the better as you get more for your power that way than you would save in not paying for grid power.When the generous feed in tariffs ended, the equation changed. Here in WA the feed-in tariff is only a fraction of the cost charged by the energy suppliers. That means it is better to use your own produced power as much as possible in preference to taking power from the grid. So north facing panels mean that your need for power is at its lowest when you are producing it at the maximum and your need for power is highest when you are producing the least. So an east or west or both direction solution can actually be the cheapest solution overall. You still do not produce as much power as when your panels are facing north, but the lesser amount being produced is more effective at keeping costs lowest overall.Obviously there are lots of provisos that go with the above. Usage of smart tariff meters, being a non-typical household, having smart appliances that can be time controlled, use of battery storage etc. all will have an impact on what is the best orientation.</blockquote>

[QUOTE="bellenuit, post: 1141812, member: 20825"] My understanding is as follows, but I am no expert. Assuming no shading, you generate the maximum amount of solar power when the panels are facing where the sun is at midday, which will be generally be to the geographic north. Household power consumption during daylight hours, particularly for working families with school going children, is generally at its highest in the mornings and in the early evenings. The mornings due to cooking breakfasts, showering (for electric water heaters) etc. and in the early evenings due to cooking dinners, maybe TV watching and in particular air conditioning usage on hot days. Air conditioning usage tends to make the early evenings more energy dependent than mornings. Middle of the day usage is low due to parents working and kids at school. About a decade or more ago, when many people were on very generous feed-in tariffs that were greater than the cost of buying power, it made sense to have the panels orientated to the north. The more power you could feed to the grid the better as you get more for your power that way than you would save in not paying for grid power. When the generous feed in tariffs ended, the equation changed. Here in WA the feed-in tariff is only a fraction of the cost charged by the energy suppliers. That means it is better to use your own produced power as much as possible in preference to taking power from the grid. So north facing panels mean that your need for power is at its lowest when you are producing it at the maximum and your need for power is highest when you are producing the least. So an east or west or both direction solution can actually be the cheapest solution overall. You still do not produce as much power as when your panels are facing north, but the lesser amount being produced is more effective at keeping costs lowest overall. Obviously there are lots of provisos that go with the above. Usage of smart tariff meters, being a non-typical household, having smart appliances that can be time controlled, use of battery storage etc. all will have an impact on what is the best orientation. [/QUOTE]

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