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Wednesday 7 February 2018

How To Save Money - 300% Returns From A Geyser Blanket

Not my geyser blanket, and definitely
not my arms! 
It’s Frugal February time again!

After last years #FrugalFeb post, there was a bit of a backlash from the readers based on their perception that my diet had degraded into one consisting of sweetcorn on toast three times a day. As a result, I have decided to keep this years' post away from dietary cutbacks and more towards manly D.I.Y. work.

Just a heads up, this post is on the lengthy side, so maybe get yourself some sweetcorn on toast a cup of coffee before you dive in.

Around the middle of every month, I receive our levy statement and electricity usage from our complex’s managing agent. When it arrives, [sarcasm] I eagerly open it [/sarcasm] to assess the damages for the month.

The electricity price increases over the last couple of years have started to have a noticeable effect resulting in it being picked up by my cost saving radar.

This lead me to do some further digging to see “watt” we could do to “zap” our bill a little (sorry, I couldn’t resist the terrible terrible puns…I know it's quite "shocking" (shit I did it again!))

As a starting point, I had a look at our electricity usage over the last year or so. To confuse things somewhat, our meter reading is done on different days of the month (I guess it depends if month end falls on a business day or not.) So some months the billing cycle is 28 days, and others 31. Then there is also the fact that electricity is charged on a sliding scale, which means the total usage and total cost has a non-linear relationship (the more you use the more you pay per kWh). And finally there are the unknowns, like when exactly tariff increases kick in, and sometimes I think they are even back dated.

All this makes the Rand value of the bill not entirely representative of what is really going on.

So to normalise our usage, and get an idea of any trends, I calculated our units used per day for each months bill over the last year. The following chart shows our usage from January to November 2017 (December excluded for reasons which will become apparent a little later on).

So the first thing that is immediately obvious – June, what's up with that!?

I remember last Winter quite well – it was rather icy.  Because Junior does not seem to appreciate the value of blankets just yet, the effect of running heaters at night to keep his room warm is quite apparent. We used around 29% more electricity during the colder Winter months.

Also, it was interesting to notice that over the more recent months, our usage has been remarkably consistent! 15kWh a day seems to be the number.

I immediately became curious whether our 15kWh a day is considered "good". I managed to dig up these survey results which made for some interesting reading. I put our home size somewhere between small and medium, and by this metric, it seemed we were more or less par for the electricity usage course. According to the "per occupant" metric we were quite far ahead, using around 5kWh per person per day, while we seemed to be worse off than most on the "per bedroom" metric (7.5kWh per bedroom per day). So all in all I guess we are pretty "normal".

In terms of cost, as mentioned, our municipality uses a sliding scale (kind of like the income tax brackets). The more electricity you use, the higher the cost per kilowatt hour. Out of interest I calculated a cost per day for the last year. The chart below shows the result (excluding December again).

You can see the effect of the sliding scale - the 29% increase in usage during the colder months equated to around a 44% higher electricity bill! June peaked at over R42 a day.

But the sliding scale thing can actually work in your favour too – because any kilowatt hours you are able to save, get deducted from your bill at the highest kilowatt hour rate you pay. So that offers some motivation!

So the question was, what should I target to get our usage down?

Now when it comes to saving on electricity (or anything else for that matter), I want the biggest bang for my buck. I want to target the stuff that will give the most benefit for the time, money and effort spent. After reading some stuff on the interwebs, it became apparent that the geyser is king of the electricity bill. The 2 extracts below (from this article and this article) pretty much sums it up:

“Your geyser is probably the most energy-consuming appliance you might own. On average, it represents between 25% and 40% of the total amount of your electricity bill.“ 

“Your electricity consumption is dominated by one appliance, and that is your geyser. The average geyser is anything from 3kw to 4kw and is an electroholic when it comes to energy consumption.”

Okay Mr. Geyser, you and me need to have a chat.

After the very one sided conversation with my geyser, I started checking out ways I could reduce it's electricity consumption. There are roughly 4 things you can do:
  1. Turn the thermostat down. This doesn’t cost a thing, and requires no ongoing effort. Easy win! 
  2. Install a geyser timer – manual or automatic. You could manually turn your geyser on and off when you need it, or you could install a timer to do it for you. However my understanding is this may not be that effective. Reheating a cold geyser takes an immense amount of power and may not be that effective over shorter on-off cycles. The thinking seems to be that if you can switch it off for more than a day at a time it may be worth it, but for less than that don’t bother.
  3. Install a geyser blanket. Geysers lose heat to the surrounding air all the time. This means the geyser switches on to reheat the geyser every now and then as heat is lost. A geyser blanket slows down the heat loss, resulting in less reheating. 
  4. Get a solar geyser. Probably the most effective energy saving option of all, but with a hellishly expensive price tag, this is not an option for us at the moment.
I decided I would implement two of the above options. The ones that made the most sense:
  1. Our water seems hot enough – turn down the thermostat
  2. Install a geyser blanket.

How Much Does A Geyser Blanket Cost?

I went and priced geyser blankets towards the end of last year. They generally cost in the region of R150. Obviously some were cheaper and some were more expensive, but either way it is not a lot to fork out for something that will save you money month in and month out.

How To Install A Geyser Blanket

In theory, the installation of a geyser blanket is as follows (shamelessly copy pasted from my geyser blanket manufacturer's website)

This seemed easy enough….right?

Here’s how it played out in practice:
  1. The blanket comes in a rectangle measuring 1.5m by 2.4m. This is great because you can just cut it to size – so good enough for almost any geyser. I found some measurements for the “standard” geyser sizes on the packaging. Our geyser had a sticker saying it was 150 litres. But just to confirm, I climbed up into the ceiling and measured the geyser’s length – 115cm. Hmmm, that wasn't equal to the predefined 150l measurement on the packaging – interesting. But anyways. I measured the diameter too - 50cm. 
  2. Back down the ladder, and time to cut. Luckily we all remember our high school Maths, and we know we could determine the size of the rectangle to cut by calculating the circumference of the geyser = (2)(Pi)(r). So I cut a rectangle of 115cm by ~157cm.
  3. Then I cut out the end caps from the remaining material. I just did a square of 50cm x 50cm since cutting a circle seemed like something I hadn't done since pre-school and I figured the corners of the square could be folded over the edges and secured with duct tape.
  4. I was left with a couple of strips of material, which would be good enough to cover the outlet pipes.
  5. NB - Switch geyser to OFF at the DB Box, I didn't want a funky new hairstyle. If you unsure where the geyser breaker is, rather just put the Main Circuit breaker off. If you unsure where the main circuit breaker is, rather just put everything off.
  6. Back up the ladder with all the material. Helpful hint – wives work really well for passing tools, material and cold beverages up into the ceiling while you're working.
  7. I noticed that the geyser also had a switch in the roof. Just to be doubly sure, I switched that off too. 
  8. I unscrewed the plate at the end of the geyser to get to the thermostat. The set point is adjusted on a variable resister using a screwdriver. Ours was set to the max. I had previously read that the markings on the thermostat can be inaccurate so I guesstimated a setting and closed everything up again. I thought I would leave it at the reduced setting for a few days to see if Mamma Bear’s bath water was too hot, too cold or just right. (My guess seemed to be good enough. The water is now not as hot as it used to be, but definitely still hot enough. This really was an easy win.)
  9. Something I was aware of from the beginning was that the geyser blanket installation instructions conveniently showed a free standing geyser, whilst our geyser was fully installed and comfortably resting on a tray. As a result I knew I wouldn’t be able to wrap the blanket all the way around, but I tucked it under as best I could, and secured it with duct tape - but not just any duct tape.... How cool is this Mr Money Mustache style type I found (which in true MMM style actually cost less than the other options!)

    Mr Money Mustache duct tape - pure awesomeness!

  10. Next up I did the outlet pipe. My son's bath time had ended about an hour earlier, and so I could easily distinguish the outlet pipe from the inlet pipe, because it was still warm. And that's exactly the point of insulating the outlet pipes -  the next person to run hot water will receive the already heated water that has been snuggling under the blanket on the outlet pipe. This means faster hot water out the tap, and less cold water into the geyser which needs to be heated up. Make sense? I did as much of the outlet pipe as the amount of material would allow.
  11. Done – total time for everything I would put at around 2-3 hours (although that is a guess because when you have a child there are very few tasks that can be done from start to finish without interruption, and this one was no exception taking around 4 sessions to complete!)
  12. Not quite done! Turns out yours truly forgot to turn the switch in the ceiling back on! After the second day this became immediately apparent by the ice cold water coming out the hot taps. Oops! Back up into the ceiling!
And that was it. Not too bad. And let me just say that I am not exactly a typical D.I.Y. kinda guy. I am far more comfortable behind a keyboard than with a drill in my hand, so If I could manage I'm pretty sure anyone can.

Now a couple of disclaimers for those wanting to attempt something similar.

Man oh man, up in the ceiling it is:
  1. Dark 
  2. Confined and
  3. Hot. Very hot. It’s almost as if there is a geyser up there!
So you are going to need a torch and clothing is optional which is cool. There will be a lot of awkward bending and uncomfortable yet careful manoeuvring as, depending where your geyser is situated, the ceiling gets pretty low in some parts, and you should only stand on the roof trusses. I don’t think your significant other would appreciate you stepping directly on a ceiling board and then dropping straight through to surprise them. When I was done it felt like a proper workout, and I was sore in some interesting places!

And very important – make sure the geyser is off before fiddling with the thermostat or installing the blanket.

Did It Work?

Our electricity bill for December has arrived - hot off the press! Opening it very eagerly to see the results of my efforts....

I plotted the same graph as previous, but this time with December included. The blanket was installed on the night of 19 December, and so it was included for around a third of the December billing cycle.

Well would you look at that! Down from ~15kWh per day to 13.22kWh per day. I must be honest this result surprised me! Seems like too much of a saving? Maybe accidentally having the geyser off for two days also contributed?

Either way I am quite chuffed and definitely not complaining! Long may it continue!

I will keep an eye on the readings going forward, but I am thinking that our electricity bill should be at least R50 a month less. That works out to R600 a year.

R600 back on something that cost R150 - that's a 300% return!. Most scams can't even offer that!

All in all seems like something I should have done a lot sooner.

What To Do With The Savings?

With regards to the way I budget for our electricity expense, I usually allocate an amount above what the bill usually comes to - basically I over-budget and then under-spend. The reason I like to do this is that if there is a month with a very high bill (such as June last year) it won't trash our budget.

With my geyser now sleeping slightly cooler and in a snug blanket, I am expecting the under-spending to happen often, and by a larger amount.

Great! So this means we will have more money to spend in the month?


I like to make sure that saving really is saving. So I will take any money left over from the electricity budget each month and put it into my newly created energy-savings savings – a savings account set up specifically to be spent on future energy savings projects (and to absorb any possible overspend if, for example the next winter is a repeat of last year). In reality, I am not actually setting up a savings account, I will simply stash the money into my bonds access facility and keep track of it in an excel spreadsheet.

As to what energy saving project to tackle next – I am hoping you guys could maybe help me out? Drop some ideas in the comments section!

Also, if anyone has undertaken any energy savings projects of their own, I'm pretty sure the blogs readers would be keen to hear about it (I certainly would!) How did it turn out? Fire away in the comments...

Till next time, Stay Stealthy!
 - ~ - ~

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