Does switching your geyser off save electricity - A simple experiment

PJS said:
This site/ product seems to disagree: http://www.wattsup.co.za/index.html
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They would, as they are trying to sell something for XXX that a geyser blanket would do for X (and possibly turning down your thermostat).

All they "Claim" that they are saving is the reheating spikes (which you will see as a loss factor plated on the side of most modern geysers, for a set test temperature/environment, and detailed in AlanB's tests).
 
Go for Solar

A solar heating system can save you up to 90% of your heating costs.
It is a costly investment, but with a 20% anual increase in Eskom rates, you can have a payback period of 5 years.
We in South Africa (Cape Town) have high radiation. 3.2kWh Winter average and 8.1kWh Summer Average.
Invest in 'n good solar system and you will have performance even during cold winter days. During summer, you will have perfect performance and can turn off your electrical back up, and still have hot at 65°.

Only a few solar geysers are insulated in a way that you don't need a geyser blanket, although, this is always a good idea.

Not everyone can afford this, but it's also not out of reach.
 
Well, for those who cannot afford this, and realistically speaking these are hard times, I propose my system, which weighs in at a whole R440 + VAT and is compatible with the ripple control system.
 
Turiko said:
Well, for those who cannot afford this, and realistically speaking these are hard times, I propose my system, which weighs in at a whole R440 + VAT and is compatible with the ripple control system.
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Cool, thanks Turiko, when i figure out what it is, I'll use it :)
 
Geyser-Off Debate

Greetings,

Many have posted their findings after switching the geyser off during the day. The past two months I've been doing the same, on average my 1,500W geyser was only on for 1 hour in the mornings and 1,5 hours in the evenings, I could thus never use more than 3.75kW per day to operate the geyser (R55 per month at R 0.49/kWh). I'm still checking my records to see how these figures compare with leaving it on.

My thermostat is currently set to 60 degrees. Since most thermostats have an operating range to prevent excessive switching, mine will switch off at about 70 degrees and on at about 50 degrees. If I were to leave my geyser on the whole day and shower at night the water temperature could be anywhere between 50 and 70 degrees. The lower range is fine for showering but not so good for running a bath. Here it would benefit me to switch the warm geyser on at 7PM if I wanted to have cooking water at 8PM.

It seems true savings are only reached by turning the temperature down from the default 75 degrees to 60 or even 55 degrees, and by increasing the temperature of the supplied water through the use of solar water heating.
 
Ralf_CT said:
Greetings,

Many have posted their findings after switching the geyser off during the day. The past two months I've been doing the same, on average my 1,500W geyser was only on for 1 hour in the mornings and 1,5 hours in the evenings, I could thus never use more than 3.75kW per day to operate the geyser (R55 per month at R 0.49/kWh). I'm still checking my records to see how these figures compare with leaving it on.

My thermostat is currently set to 60 degrees. Since most thermostats have an operating range to prevent excessive switching, mine will switch off at about 70 degrees and on at about 50 degrees. If I were to leave my geyser on the whole day and shower at night the water temperature could be anywhere between 50 and 70 degrees. The lower range is fine for showering but not so good for running a bath. Here it would benefit me to switch the warm geyser on at 7PM if I wanted to have cooking water at 8PM.

It seems true savings are only reached by turning the temperature down from the default 75 degrees to 60 or even 55 degrees, and by increasing the temperature of the supplied water through the use of solar water heating.
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When doing your calculations you need to take into account:

1. Check the period (number of days) for which your account applies, accounting periods can vary
2. You need to measure the amount of hot water being used, as this is the major criterion which will affect the amount of electricity being used.
3. Do you have sufficient hot water from the cylinder when switching on and off as you are now doing?

I agree with your final paragraph.
 
Electricity Usage

We recently moved into an apartment with a pre-paid meter which allows us to track our daily kW usage. Since my last post I've decided to leave the geyser on (at 1 hour in the morning and 1.5 hours in the evening the water was hot [the thermostat had switched off according to the flashing light on the meter]). Each morning after I get up at +-07h00 I make a note of the kW reading. Having done this for the past 6 weeks I've arrived at a daily average of 11.5kW. On weekends we use more (heater, washing machine), during the week we use less.

Interestingly, leaving the geyser on actually reduces the daily electricity consumption by almost 1kW. It seems our thermostat is rather sensitive with its operating range being between 55 and 65 degrees when set at 60. The set temperature is reached pretty quickly at 1,500W, and it stays there. Geysers are well insulated and cannot be compared with a kettle. Ours is still an old combination geyser which works well but doesn't allow for a shower, and when running a bath this has to be done in two stages.

The only ones to benefit from switching the geyser off seem to be ESKOM thereby reducing the load on the national grid at specific times. We aren't saving.
 
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Ralf_CT said:
The only ones to benefit from switching the geyser off seem to be ESKOM thereby reducing the load on the national grid at specific times. We aren't saving.
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Correct. The whole geyser switch off thing has nothing to do with saving. It has everything to do with moving consumption to a more convenient time for the supplier
 
I am about to build a house and it has been suggested to me that i put in 20-30L geysers, one in each of the 2 bathrooms (we shower only) and one in the kitchen, perhaps even a smaller one in the kitchen. Can anyone tell me whether this would save on electricity. Basically we require 3 hot showers a day and a couple of sinks of hot water, it seems unnecessary to maintain 150L at 55deg for the entire day for this.
 
LED lights

Hello everybody,

I know this reply is off the topic, but we are all trying to save electricity, so it might come in handy.

Why not change to LED lights? We have all seem them at the hardware shops, the brands of LO.... and OS... The most common comment is they are not bright enough. Correct! Those ones are not. These ones are!!!

Please go to
www.c2r.co.za
to have a look at the range that is available in SA.

For example a fully dimmable fluorescent replacement tube that does not need a starter and ballast to work, although they will work with them. Or a fully dimmable globe.

6 Watt downlighters that give the same light as a 50 Watt halogen, in either the 12v or 220v versions. A 88% saving in electricity. The 12v version is dimmable because of the transformer.

There is also a 2 Watt downlighter that looks the same as the name brands from hardware stores, but this version gives more light, I have put them side by side in my bathroom. A 96% saving in electricity.

The lifspan is amazing:
Tube replacement is 80 000 hours.
6Watt downlighter is 30 000 hours.
BulbLED is 40 000 hours.

A little something to ponder: we have to stop thinking of LED lights as consumable items. Like toilet paper, we use it, its finished, we buy more. Same as tungsten and CFL lights, because their lifespan is so short. NOT LED's, they last too long.

The calculation is as follows:
Using a bulbLED (http://www.c2r.co.za/html/bulbs___do...s.html) (scroll down) outside your front door, at 40 000 hours for a LED, at 10 hours/day, 7 days/week = 10 years.
Now using a bulbLED as a bedside lamp at 1 hour/day, 7 days/week = 100 years.
Your grandchildren will use the LED's that you will buy.

Look at your light use habits at home, analyze what lights are on for longer periods
than other lights. Change the longer ON lights first, that will have the bigger, more immediate impact in reducing your electricity bill.

The more hours per day lights burn, the better LED's become.
The higher the Rand per KW hour is, the better LED's become.

Look around at night, how many lights are on. Chop that by 50%. Imagine that right now! Then put in occupancy sensors, that switch the lights off when nobody is around.
We have them, but they are very new to us. Watch the website for them.
Now combine LED's and occupancy sensors. Imagine that electricity saving!

Yes they are expensive, but calculating a total cost of ownership
the lights will save you money in the end.

For the environment friendly people, remember
that LED's contain NO Mercury.

Imagine SA wihout any loadshedding.
Applications exist for any situation, Industrial, Commercial,
Residential.
 
Maginxa said:
I am about to build a house and it has been suggested to me that i put in 20-30L geysers, one in each of the 2 bathrooms (we shower only) and one in the kitchen, perhaps even a smaller one in the kitchen. Can anyone tell me whether this would save on electricity. Basically we require 3 hot showers a day and a couple of sinks of hot water, it seems unnecessary to maintain 150L at 55deg for the entire day for this.
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Bingo, well thought, but for kitchen and hot showers look at the instant electric boilers. Only heat the water you use as per convenient heat setting.
 
I am no scientist but I am a consumer that has monitored the usage of the Geyser and the cost attached to keeping it on 24/7 opposed to the On/OFF method.

In 1994 I moved into a house that had those Municipal prepaid boxes. Well I bought R100 (that was money back then) electricity this kept me for the month (2 adults only) with the geyser on. My mother was appalled at this cause she believes non essential Elec equipment should be turned off (except the VCR that records the soapies :D)

The next month I did what my mom STRONGLY suggested and guess what. The R100 elec I bought lasted me for a month & a half. I have been doing just that ever since. we are now 2 Adults 1 Teenager(Flat Iron, Hairdryer etc) and a 9 year old. Well I use MORE that R100 but it goes further now just because I turn off the Geyser when there is nobody at home :p
 
geyser consumption

ok, so I'm one of those late joiners. the consumption spreadsheet, ,is it readily available?. I'd hate to have to re-invent the wheel, rgds
 
lenro said:
ok, so I'm one of those late joiners. the consumption spreadsheet, ,is it readily available?. I'd hate to have to re-invent the wheel, rgds
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Go have a look on the first page. The link is posted there.

This is quite enteresting. I am in the process of bringing in tankless water heater systems. It only consume electricity when you use it and will have(according to the figures provided here) up to a 30% saving on a tank type geyser.


I am installing mine tomorrow and if you guys are interested I will post some stats as I am finally be getting my prepaid meter which will assist in the stats.
 
onerb said:
Go have a look on the first page. The link is posted there.

This is quite enteresting. I am in the process of bringing in tankless water heater systems. It only consume electricity when you use it and will have(according to the figures provided here) up to a 30% saving on a tank type geyser.


I am installing mine tomorrow and if you guys are interested I will post some stats as I am finally be getting my prepaid meter which will assist in the stats.
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We should all use this kind of thing. My flat is 50m^2 to have a frikken huge geyser in there is crazy. This thing:
a) never runs cold, it can pump out hot water all day
b) is available on demand- as mentioned, as much as 30% more efficient
c) probably cheaper to install and maintain
d) less/no damage due to bursting
e) saves space

These things have been available for years, yet they have not become the standard in flats. WHY?
 
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