Extra panels or Solar Geyser?

[newby_investor]

You’ll be surprised.

I’ve had plenty of
I just wouldn’t bother with the generator at all. Use the grid to avoid the load shedding and call it a day.

Yeah this is a fair point. It depends on your needs.

I personally wouldn't bother adjusting my usage upwards, I'd rather spend as little as possible to get a 95% system based on my current profile then use a gen to top up for that odd few days per year. Just charge the batteries then switch off the gen again until tomorrow or whatever.

I'm curious about your use of heaters though. I'd have imagined that with aircons you wouldn't need them.

 

[Fcon_Vpro]

I had two cuts of 17 and 22 hours so far this year.


I’ve only had solar for a week, I’ll have to make a plan with the geyser.
I want to be able to go 24 hours without Eskom or sun, but I didn’t think of the consequences of 24 hours no geyser. Can still live with the oven off.

The following is not a solution for everyone but works well for me.

I have a portable gas geyser that I use
during extended outages from city power/eskom.
I fill the bath with cold water. It has a 12v pump that I put into the bath and I just rotate the water through the geyser and back into the bath for a few minutes and then it's at the right temperature. The bath part works for my wife and child.
For when I need to shower, there is a 10L bag and shower head that can be connected to the geyser.

The Alva portable gas geyser cost me R2500 and I use it for camping as well. So outside of the gas I use, the other "cost" is the setup time for me ie taking it out of garage and getting it going. 10min Max.

I have a 5kw sunsynk and 5kwh battery.
I have a 200L geyser with 4kw element on non essentials circuit. It runs 9am-4pm and the hot water lasts until the next morning.
When loadshedding starts at 8am or 10am, then water gets a bit colder.
I also have a generator connected to my aux port so cant connect non essentials to aux port.

If I wanted to support my geyser I would need to spend another R15k to get 8kw sunsynk and then have it on essentials.
I'd also need more batteries when there is no grid support so potential R30-R60k extra for 1-2 batteries.

If I put in a smaller 2kw ptc element with current setup, it would cost around R3k with installation and would take me around 4 hours everyday to heat up water vs the 2 hours I need now.

Fixed gas geyser would cost me extra monthly for gas and also installation cost.

Solar geyser also pricey ie R20k+

After I weighed up all my options I find my portable gas geyser works perfectly for the 3 or 4 times a year I need it during extended outages.

 

[SauRoNZA]

What happens on day 2 of black skies?

Eskom happens.

 

[Tomtomtom]

No aircon in night ? We also 2.5 but our consumption is about 13kW per day. We cook nearly every day, twice per day.

No aircon here but we had one in our last place and it probably only added a unit a day.

I just find it interesting many people seem to have consumption 3-5x ours... A whole different level.

Like my usage went from 25kW a day to 45kW a day because I now generate my own power.

So I don't know how I would physically do this during summer.

 

[SauRoNZA]

Yeah this is a fair point. It depends on your needs.

I personally wouldn't bother adjusting my usage upwards, I'd rather spend as little as possible to get a 95% system based on my current profile then use a gen to top up for that odd few days per year. Just charge the batteries then switch off the gen again until tomorrow or whatever.

I'm curious about your use of heaters though. I'd have imagined that with aircons you wouldn't need them.

Why use the generator to charge the batteries?

And when I said heaters it was a universal term for heating as I don’t have an aircon in every room and haven’t tried running the three aircons all day every day like I did during summer just yet.

 

[SauRoNZA]

No aircon here but we had one in our last place and it probably only added a unit a day.

I just find it interesting many people seem to have consumption 3-5x ours... A whole different level.



So I don't know how I would physically do this during summer.

Because there is no way on earth your single aircon added only one unit a day if it ran all day.

And I have three.

Add to that using a tumble dryer I never used before. Running the dishwasher twice as often etc.

 

[wingnut771]

Eskom happens.

The substation is burning.

 

[Tomtomtom]

Because there is no way on earth your single aircon added only one unit a day if it ran all day.

And I have three.

Add to that using a tumble dryer I never used before. Running the dishwasher twice as often etc.

Never ran it all day, just a few hours at night, and not fridge cold, so with duty cycle 20% or so it could easily be only a kWh.

Tumble dryer in summer?

But I do see how consumption would go up one way or another when it's a use it or lose it situation.

 

[Tomtomtom]

That's a factor, but he's using more grid than he's exporting.

The issue is his SOC is high and he topping up the batteries from the grid. And this is using more than he's exporting.

View attachment 1486849

He doesn't need to buy anything more, just needs to start making better use of what he already has...

Curious, is there a reason why a system would be set up like this in the first place? Battery kept on standby, despite solar PV?

Not sure I'm understanding the export aspect but is that it, the grid is the cheaper battery to be used first in this case?

So then why change the setup at all?

 

[The Darkness]

Why not install a heat pump in place of the geysers? Huge difference

 

[wingnut771]

Why not install a heat pump in place of the geysers? Huge difference

The geysers are free and are just wired up in the wrong place?

 

[SauRoNZA]

Never ran it all day, just a few hours at night, and not fridge cold, so with duty cycle 20% or so it could easily be only a kWh.

Tumble dryer in summer?

But I do see how consumption would go up one way or another when it's a use it or lose it situation.

If it’s free why not?

But yeah normally I wouldn’t use it in summer…or winter unless desperate.

Now it means getting way more washing done and dusted.

Mine are all set to 25 degrees, will be 18 in winter

 

[Vorastra]

Anyone know how cost effective it is if we were to do like what Europe does, where water is heated by gas as you use it?
Is that even available here?

 

[Paulsie]

Anyone know how cost effective it is if we were to do like what Europe does, where water is heated by gas as you use it?
Is that even available here?

It's slightly more expensive to run it on gas than on eskom, but exponentially more so than if you already have a well functioning solar system.
Also, there are regs as to where it can and cannot be installed (1.5-2.5m from windows, doors etc) plus the added inconvenience of having to change gas bottles (whereas in Europe you have a central gas line running into your house).

 

[Vorastra]

(whereas in Europe you have a central gas line running into your house).

Not where my family's place is lol
We get cans delivered like they do here.

So running a gas geyser which only consumes gas during the time the hot water is being used, is more expensive than a geyser that's on all day?
Damn...

 

[SauRoNZA]

Not where my family's place is lol
We get cans delivered like they do here.

So running a gas geyser which only consumes gas during the time the hot water is being used, is more expensive than a geyser that's on all day?
Damn...

A geyser isn’t “on” all day.

I’m sure gas is cheaper, just a question of whether it’s cheap enough compared to the inconvenience.

Personally I hate it for the inconsistency, both in heating and in cooking.

 

[Vorastra]

A geyser isn’t “on” all day.

Jesus Christ, must we now argue about standing heat loss.

You know what I mean. A geyser is on more of the day than a gas geyser would be.

Example from the page for the Kwikot Superline 400 DUAL 200L

• The polyurethane insulation between the inner cylinder and the outer galvanised casement is 128% thicker, resulting in the hourly standing heat loss decreasing from 108 watts per hour to 50 watts per hour.

50 watts per hour on average, every hour, of every day.

Some may colloquially call this..."on all day".

 

[Vorastra]

I’m sure gas is cheaper, just a question of whether it’s cheap enough compared to the inconvenience.

What inconvenience can you mention. When I go overseas and use it for showering for example, it's automatically activated by the movement of water and the water is heated very quickly.
Maybe we have different systems? Not like mine is new though. It's quite old IIRC.

Personally I hate it for the inconsistency, both in heating and in cooking.

You're going to have to explain by what you mean by inconsistency. Like what for example?

 

[Paulsie]

Not where my family's place is lol
We get cans delivered like they do here.

So running a gas geyser which only consumes gas during the time the hot water is being used, is more expensive than a geyser that's on all day?
Damn...

We actually use them at work where we require large quantities of constant supply of hot water.
Having said that, my plumber borrowed a spare one of mine to run trials.
After about two months, he ascertained the cost of gas is slightly more expensive than the cost of electricity for a standard water geyser.

Caviat: it all of course depends on circumstances, ie the number of people, the number of times water is used, timers etc (I have a spare geyser in my downstairs bathroom and use shower once a day). In summer, I can run 3 days of showers without switching it on.

Lowdown - if you do not need hot water 24/7 or do not have too many people in the house using it, put a timer on it and stoci with an electric one.

 

[Vorastra]

We actually use them at work where we require large quantities of constant supply of hot water.
Having said that, my plumber borrowed a spare one of mine to run trials.
After about two months, he ascertained the cost of gas is slightly more expensive than the cost of electricity for a standard water geyser.

Caviat: it all of course depends on circumstances, ie the number of people, the number of times water is used, timers etc (I have a spare geyser in my downstairs bathroom and use shower once a day). In summer, I can run 3 days of showers without switching it on.

Lowdown - if you do not need hot water 24/7 or do not have too many people in the house using it, put a timer on it and stoci with an electric one.

Shot. Actually that'd be a fun little distraction. Working out the cost of a gas geyser and an electric geyser.
Hmmmm.....