Loadshedding solutions

[LazyTrailRider]

16 hours ago, ChrisF said:

EDIT - He confirmed that they are using 15 to 18 kW.h on the bad winter days.  Certainly should be over producing during summer.  Obviously the question is how deep you want to go down this rabbit hole ....  for now he is happy that summer is taken care of and winter is below the 600kW.h mark, after which COCT has a hefty increase in the unit rates.

 

Going to be very interesting to see his annual figures .... his install was done at the start of this winter.

Yip, completely expected, and we haven't actually seen much of the usual proper winter weather (with entire weeks of rain) yet.

The reality is that the graph swings drastically in Cape Town.

Case in point (@Schnavel have a look at the JHB comparison):

https://mybroadband.co.za/news/energy/451432-why-south-african-solar-power-systems-can-underperform-in-winter.html

 

[Schnavel]

24 minutes ago, LazyTrailRider said:

Yip, completely expected, and we haven't actually seen much of the usual proper winter weather (with entire weeks of rain) yet.

The reality is that the graph swings drastically in Cape Town.

Case in point (@Schnavel have a look at the JHB comparison):

https://mybroadband.co.za/news/energy/451432-why-south-african-solar-power-systems-can-underperform-in-winter.html

 

Thanks for sharing - I didn't realise you were in Cape Town. 

Amazing how much of a difference it can cause, but you must then have plenty of supply on those long, sunny Summer days. Maybe worth investing in a wind turbine for the rest of the year? A constant 1kW from the wind will go a long way to offsetting your usage, and there is definitely no shortfall in that resource in the cape 🙂

[TheoG]

I have the following setup:

Solar Panels:   10 x 455W = 4550 W (2 are dedicated to supply the geyser element)

Inverter:  5kVA

Batteries:   4 x 200Ah GEL

My average daily use is 6.72 kWhr (205.8 per month or R312) now in winter and that is without dipping into the batteries at all at night.

I cycle the GEL batteries as little as possible (only during load-shed at night) in order to get max life out of them.  Clearly I could use far less if I had Li batteries and cycle them every night.

Didn't have the funds yet to pull the trigger on Li batteries but soon ... very soon .

PS:  I use zero Escom on my geyser, we are only 3 adults in the house and the geyser is 150 liter.  Sun power is sufficient to provide us with hot water even now in winter.

[MongooseMan]

Here's my monthly production over the last ~2 years (21x 410W panels, 15 NE facing, 6 NW facing).

Some of this (mainly the summer months) is capped by demand (if the batteries are full and there's nothing on in the house, you stop producing if you're not pushing power back into the grid).

[Shebeen]

15 minutes ago, Schnavel said:

Thanks for sharing - I didn't realise you were in Cape Town. 

Amazing how much of a difference it can cause, but you must then have plenty of supply on those long, sunny Summer days. Maybe worth investing in a wind turbine for the rest of the year? A constant 1kW from the wind will go a long way to offsetting your usage, and there is definitely no shortfall in that resource in the cape 🙂

I actually did a mini thesis on this in 2010 comparing the options for different types of users in the main centres around CT! solar won everywhere (when panels were ~5 times the price of now).

 

The problem with wind is you need consistency. The breeze in cape town winter is crap. either very calm or gusty strong. they also flippen noisy and ineffecient in any size for small power use. there's a reason you don't see much installed.

 

[dave303e]

19 minutes ago, Shebeen said:

I actually did a mini thesis on this in 2010 comparing the options for different types of users in the main centres around CT! solar won everywhere (when panels were ~5 times the price of now).

 

The problem with wind is you need consistency. The breeze in cape town winter is crap. either very calm or gusty strong. they also flippen noisy and ineffecient in any size for small power use. there's a reason you don't see much installed.

 

noisy and maintenance intensive. You have something spinning 24/7. Drive the freestate, count how many wind pomps you see in running condition vs standing doing forkall/broken...

[LazyTrailRider]

19 minutes ago, Shebeen said:

The problem with wind is you need consistency. The breeze in cape town winter is crap. either very calm or gusty strong. they also flippen noisy and ineffecient in any size for small power use. there's a reason you don't see much installed.

 

Yup. They're expensive, inefficient, require maintenance, need to be installed on a massively reinforced base and are way too noisy for urban use. We live in a densely populated area and our plot is only 500sqm, so the only semi-feasible installation point would be 3m from someone's bedroom window in the next-door townhouse complex. Nope.

[Frosty]

13 minutes ago, MongooseMan said:

Here's my monthly production over the last ~2 years (21x 410W panels, 15 NE facing, 6 NW facing).

Some of this (mainly the summer months) is capped by demand (if the batteries are full and there's nothing on in the house, you stop producing if you're not pushing power back into the grid).

Here's mine, but includes the split between grid usage and solar to give a total usage (kWh per month).

[Frosty]

Guess which two days in the week we have the maid working... washing, ironing, vacuuming, etc.

[TheoG]

We have the maid one day a week, the consumption for that day is also much more than the other days 🙈

[The Ouzo]

Has anyone done a Solar conversion to a standard geyser ?

Right now the bulk of my usage is to the geyser, even with having it on a timer, I'd like to reduce that.

[dave303e]

2 minutes ago, ouzo said:

Has anyone done a Solar conversion to a standard geyser ?

Right now the bulk of my usage is to the geyser, even with having it on a timer, I'd like to reduce that.

no, but we have switched to gas geysers, a small one in kitchen and a large one for bathroom, makes no sense to have water warm all day sitting in a tank when you can heat it up instantly when needed. Also having 2 smaller ones makes for redundancy and you don't sit waiting for hot water to run from one end of the house to the other.

[TheoG]

11 minutes ago, ouzo said:

Has anyone done a Solar conversion to a standard geyser ?

Right now the bulk of my usage is to the geyser, even with having it on a timer, I'd like to reduce that.

Yes I did.  2 x 455W panels and controller feeding a dual element (solar & escom) in the geyser.  I also have a Geyserwise timer but it is hardly ever required to use escom to heat the geyser.

One of the best R19k I ever spent.

Edit:  You can convert your existing geyser to either vacuum tubes or solar panels like mine.  I chose the panels since no plumbing is required hence an easier cheaper install.

Edited July 19, 2022 by TheoG

[TheoG]

5 minutes ago, dave303e said:

no, but we have switched to gas geysers, a small one in kitchen and a large one for bathroom, makes no sense to have water warm all day sitting in a tank when you can heat it up instantly when needed. Also having 2 smaller ones makes for redundancy and you don't sit waiting for hot water to run from one end of the house to the other.

True but heating my geyser is not costing me one sent, don't have to buy gas and that is also getting very expensive ...

[ChrisF]

17 minutes ago, ouzo said:

Has anyone done a Solar conversion to a standard geyser ?

Right now the bulk of my usage is to the geyser, even with having it on a timer, I'd like to reduce that.

 

We did the Geyserwise dual element conversion about 7 years ago. Payback took 3 years,

 

About 900W worth of PV for the second element.

 

Summer time all our heating comes from this.  Mid winter we do use a bit of eskom .... with the Dual timer it is possible to set up different temperature and time zones, so easy to optimise the usage vs PV generation.

 

Biggest challenge is human behaviour ...

[The Ouzo]

Thanks

 

Anything to look out for ? Not do ? Must do ? Stay clear of ?