An economic argument against Christmas Trees

Last year Jaco installed my very nice system. The solar bit comprises a 15 panel NE facing array, and a 6 panel NW facing array. This discussion is about the NW array.

When installed, in October, the PV graph for that array was nice and bell shaped.
Come March, there started to be a dip around lunch time, before returning to a nice peak at around 3 - 4pm:

At first I was concerned; was my MPPT playing up, a wiring issue maybe?
Then I went for a walk outside at 12 one day to see what was up, and saw this guy casting a big-ass shadow over all 6 panels:

Turns out, as we get closer to winter, the sun has moved in a manner that sends it behind the Christmas tree over the peak period.

So, since neither my wife nor I actually like the Christmas tree, we’re going to get it removed, and replace it with a smaller tree (but one that still gives shade to the garden). And, since it’s costing me PV production, I can actually work out how much that replacement with “earn” me.

Cost to remove tree: R11000
Cost of new tree: R2000
Total replacement cost: R13000

Now, I can estimate how much PV production the tree is costing me. Eye-balling the graph, I conservatively estimate around 3kWh a day. Since it’s autumn, and going to get worse, I’ll keep that as a year-round average.
Cost per kWh in CT is currently R2.91, which means I need to generate ~4450kWh to replace the tree, assuming no electricity price hikes.
So, payback period is about 4 years, probably 3 after price hikes are factored in.

And we get a nicer tree (which the kids will be able to climb) into the bargain :slight_smile:


+1 for removing the tree. As far as I know it’s not indigenous.

If you are in the northern parts of SA you could go for something like the “Wit Stinkhout”. They are easy and decent fast growers, but don’t get too tall. :slight_smile:

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Nope, I’m in Pinelands, Cape Town.
So need something that can grow “on a beach”, since our soil is… not good. :see_no_evil:

Currently leaning towards a Forest Bushwillow, seems to tick most of the boxes: Combretum kraussii - Trees SA

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Good choice

Nice… also in the market for a tree. I will show this to the wife… :slight_smile:

I think these guys are near you:

If you don’t have one already, while not necessarily “pretty” or “providing shade”, no house in my mind can go without a lemon tree…

I’m sitting here in a boring room, it’s just another rainy Sunday afternoon…


Haha and while the tree can make you think of songs, there’s also an economic argument to be made for a lemon tree… given the price of lemons. Come to think of it, and avo tree probably more so.

This weekend I really wanted to get a pomegranate tree. Smallish one for R70. My neighbour has one and they seem to do well here. My wife vetoed it. Apparently “it isn’t the prettiest of trees”.

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If you are in a coastal town and you eat fish then a lemon tree is a must.
Though I don’t think they make good climbing trees

Not recommended at all, unless you have a high pain tolerance or are a masochist.

But, kids won’t be kids forever, at least not as long as a tree should live…

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And I wonder…

plant one of these, two birds with one stone, not so sure neighbors will be happy :laughing:



Not sure I’ll risk that in CPT winds.

I wonder how

Yesterday you told me 'bout the blue blue sky…

And all that I can see

Is my diminished PV?


I just a yellow lemon tree, or in this case a huge Christmas tree.

I just saw this post and thought I’d add a comment to the White Stinkwood tree suggestion.

I had one next to my driveway, it killed my sprinkler system that side and nearly severed my water and electrical supply from the council and uplifted my driveway. I had it removed due to the very aggressive root system.

My neighbor has three on our other boundary and it also killed my sprinkler system that side and is more than halfway into my plot uplifting pavement already.

Be very careful planting this tree, it gets very big but needs more space than what normal city plots can safely provide - unless you plant it smack in the middle of your garden with nothing around for more than 15m radius.