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The Terrible Triplett

Water harvesting and use, same logic as solar systems.

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2 hours ago, plonkster said:

... shared with me on social media.

Now that is something I like ... will consider doing it later this year.

Later because after having been watching prices, AND NOT DOING ANYTHING (bad bad boy), the last year+, it is quite interesting to see what people are paying today.

For example, off the top of my head:
2nd hand clean food grade flow bins: +-R450 - today, R2500 if you can get.
2nd hand clean food grade plastic drums: +-R85.00 - today R300-R400
Used food grade steel drums with lids: +-R50.00 - R85.00 - today between R170 - R500, some with cheap plastic taps added.

All I see, there is going to be a flood of drums and bins and tanks in the next 2 years on Gumtree.

This time I will be ready. ;)

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50 minutes ago, PaulF007 said:

Maak bietjie vir ons n mooi video oor jou solar sisteem met die omsetter ens. 

My garage is meer deurmekaar as my agterplaas, en daar is 'n massive 19" Rack met toerusting wat in die pad staan waarvoor ek nog 'n beter gat moet kry. So daar is nie 'n manier op die oomblik nie :-)

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On 2/9/2018 at 4:43 PM, plonkster said:

My garage is meer deurmekaar as my agterplaas, en daar is 'n massive 19" Rack met toerusting wat in die pad staan waarvoor ek nog 'n beter gat moet kry. So daar is nie 'n manier op die oomblik nie :-)

Wat is in daai "19 rak? Ek dink ek het `n gatjie in my garage vir een ;)

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5 hours ago, SilverNodashi said:

Wat is in daai "19 rak? Ek dink ek het `n gatjie in my garage vir een ;)

Dis 'n volledige development kit met alles wat ons in die Victron stal ondersteun. Daar is drie power supplies om sonpanele mee te simuleer, twee MPPTs, 'n Multiplus, 'n Fronius Primo op die agterkant, current meters, 'n BMS, en 'n CCGX. Dit maak dit moontlik om amper enige scenario met regte hardeware te toets.

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Right, it seems to me that indeed, as I suspected from day one, if the Cape does not get lots of rain in the next few months, like Jhb has had to fill their dams, even with augmentation schemes we will overall run dry, though some parts may still get water from augmentation schemes.

We tend to forget that the farmers relying on the same dams, businesses that cannot desalinate and / or use grey water, will all go under. 

The ecomony, job losses et al ... sjoe.

I quote:
Indeed, it is important to understand that we can only avoid day Zero if four conditions are met, and maintained:

  • The national Department of Water and Sanitation holds to its commitment, made at the start of the hydrological year in November 2017, that the Western Cape Water Supply System will be able to draw down 174,000-million litres of water from the dams that feed it;
  • We continue to decrease water usage to the point where each person in the region fed by these dams uses a maximum of 50 litres per day. (This is still a perfectly comfortable level of water use.);
  • Industrial and commercial water users improve water efficiency by a targeted 45%;
  • Our augmentation programmes come on stream at sufficient volumes by their target dates before the end of June.

Although the week ended with a greater degree of comfort than it began, on all four indicators, there was still one strongly negative signal: despite predictions of reasonably heavy rainfall by the end of the week, we only got a light drizzle. The impact of climate change saw the epicentre of the cold front veer away from the coastline, moving eastwards across the sea, and then north to bring rain to KwaZulu-Natal. If that pattern continues throughout this winter, as it did last year, the Western Cape is in trouble.

From here: https://www.dailymaverick.co.za/opinionista/2018-02-12-from-the-inside-dayzero-turning-a-probability-into-a-possibility/#.WoKnN29uaUk

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Day Zero has been pushed back further to the 4th of June

Water consumption over the weekend dropped to below 500 million litres per day, for the first time! 

We must keep reducing our consumption. Despite this victory, we can only #DefeatDayZero if we reduce consumption to 450 million litres. That’s 50 litres per person, per day. 

 

Message is well received, but it makes little sense if the bigger picture is not also updated - farmers, businesses etc.
 

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3 hours ago, The Terrible Triplett said:

It's the good old principle, that if something is to good to be true, it usually is. It goes both ways though: it applies also to things you really want to agree with (aka confirmation bias).

From the article: The City assumed 3.2 people per household. So on average us westerners still have 2.4 children per family, so 4.4 would have made a better figure. That remains the largest issue for me: We're 5 people. We average slightly below 50lpppd, but not below 6kl a month. By the binary measures these guys use we will never make it.

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1 hour ago, plonkster said:

It's the good old principle, that if something is to good to be true, it usually is. It goes both ways though: it applies also to things you really want to agree with (aka confirmation bias).

From the article: The City assumed 3.2 people per household. So on average us westerners still have 2.4 children per family, so 4.4 would have made a better figure. That remains the largest issue for me: We're 5 people. We average slightly below 50lpppd, but not below 6kl a month. By the binary measures these guys use we will never make it.

Perhaps you should borrow 0.6 of your children to your neighbor. Which 0.6 is up to you ;)

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YES!!! We DID it!!!

6 (six) People (4 working from home) - with a Benevolent Dictator driving the show, exactly like I would when I am Pressi ... just waiting for Zuma's call to take over.
31 days
Actual meter reading - meter was replaced a while ago, on the outside of the wall, so no more excuses for the meter reader.
Verbruik 5000l / Daaglikse gemiddelde 0.161 kl - WITH GUESTS for a week.

The 5kl is actually rounded up = 4.991kl 

 

Next move, using rainwater, with a double "First Flow" system to a portable 2300l pool then using existing pool pump and cartridge filter to pump said water to a tank next to washing machine. I hope to have the water for the washing machine as clear as tap water.
Costs: Moving gutter pipes, 1 x pool and 2 x 2nd hand plastic drums (still waiting for prices to drop).

Then my beloved wife suggested this morning:
Why do we have to let the washing machine rinse the clothes, 2nd cycle? Just use the wash cycle.
She also suggested that we must try and re-use the washing water more than once, if you have 2-3 loads one after the other.
We are going to try that, "feel" how the clothes feel.

Next target: 2500l of municipal water per month for 6 people.

 

As with solar batteries, my water "battery" is starting to take shape ito of "Ah" i.e. kl per month. 

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The Voelvlei dam from which our water is supplied is now at 17.3% and the outlet to Swartland municipality's purification installation is at 12%, all very disconcerting. I have been trying to find information on purifying grey water, bath and wash basins water in my house, for toilet flushing. These are piped seperately from sewage, kitchen sink, washing machine and dishwasher output in my house. The feed line to the toilets is a seperate feed that can be connected to the municipal or an alternate supply like treated grey water. I also have 10k liters of stored rain water for domestic use after purification.

It would seem that filtering grey water and then adding chlorine may be acceptable for toilet flushing. My pipes are all Pex synthetic pipes from Sweden and I would expect that clorine won't have detrimental effects on them. Cleaning the rainwater is still unresolved. I have an under counter RO unit  for cleaning drinking and cooking municipal water and that will probably continue to function with purified rain water. @plonkster' your purification looks just fine and I would appreciate a photo and price details if you would kindly post these, particularly the ozone generator and venturi. Ozone looks like a viable method of purifying rain water for washing and showering. I have a 1500 liter tank for storing such water and installing a pressure pump to the house. A slow flow sand filter, described in one of my books on the subject, would have high purification capabilities but is a bit of a job to construct and will need additional pumps. 

We are about 80Km from Cape Town so it is not a case of just popping down the road to buy something you need. I would greatly appreciate any and all advise and information to address the matter.

 

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29 minutes ago, ebrsa said:

your purification looks just fine and I would appreciate a photo and price details if you would kindly post these

My purification is a hack job :-) A hack that seems to work well enough. The video shows more or less everything you need to see. I'll add another one below from earlier when I was testing the concept in a bucket.

I bought the ozone generator and the Venturi from these guys. You want to talk to Ian. It was about 3.5k for a 1000mg/hour generator and the venturi. I think the price was rather steep, but I didn't want to wait for it to come across the waters. You can get the same stuff on eBay (of course), for much less, but you don't quite know the quality or how long it would take to get here. So basically I paid because I didn't want to wait :-) The quality of the stuff I got was good.

My treatment tank is a 250 liter tank made by Nel. They are not too hard to come by, it's the 1000-liter and above that tends to sell out everywhere.

The pump I have on the tank is a CRI pressure pump that does 1000 liters an hour. That means it should circulate the contents of my tank in about 15 minutes. With the Ozone output of 1000mg/hour, that means 250mg in 15 minutes, and with a 250 liter tank that means around 1mg/liter every 15 minutes. I treat it for 25, because the ozone generator has no external cooling and cannot run for longer than 30 minutes at a time.

This is where things get a bit hand-waving. Just because I put a milligram in per liter doesn't mean that I'm actually getting that kind of exposure (since some of the ozone bubbles out and drift off into the atmosphere). I do think that I get close though. Now if you look at some tables on the internet (I just googled for it), you will see that 1) the half life of ozone is around 20 minutes, and 2) even 1mg/liter kills basically anything that might be in there with the exception of cryptosporidium.

But as I said, it is a hack job. After some hours, I can visually see coagulated junk drifting around in the water, so visual inspection tells me it does work. I then put in the floculant only to drop the cloudy stuff out of the water.

Now...

42 minutes ago, ebrsa said:

Ozone looks like a viable method of purifying rain water for washing and showering

Ozone is complete overkill for rainwater. For rainwater, you want to use a sediment filter in case there's some dirt from the roof in there... but rain water is practically clean already. We used to drink that stuff straight from the tank when I grew up. Rain water is also slightly acidic (carbonic acid, due to reacting with carbon dioxide on the way down), and this tends to preserve it somewhat.

44 minutes ago, ebrsa said:

trying to find information on purifying grey water

I'm not sure about using Ozone for grey water. Ozone's sole claim to fame is merely that it extremely unstable (not explosion unstable, but I-have-an-extra-atom-to-shed unstable) and so it oxidises everything in its path (I have no idea how the pump will hold up... I guess I'll find out). It is extremely effective at this. So it works well whenever you have dissolved stuff in the water that you want out. And it also kills things. If you read some posts on forums of aquarium/fish people... there are some people on there messing with ozone, the advice is to be careful: It kills even larger organisms such as fish!

But there are some stuff that gets nastier when you oxidise them. You don't want to chlorinate before oxidising, and besides, powdered chlorine is in itself an oxidising biocide.

That is to say: I don't know if Ozone is a good idea for grey water. I'm not saying it is a bad idea. I'm saying I don't know. More study is needed.

This is the previous video where I was testing it in a bucket:

 

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1 hour ago, ebrsa said:

I also have 10k liters of stored rain water for domestic use after purification.

in order to get the stored 10kl of rain water potable add 500ml of household bleach which on average contains 3,5%mv sodium hypochloride. there might be a slight resultant odour and taste but that will vanish in a couple of days, do this every month [250ml bleach to 5kl water].

apart from that install a smallish [500mmx500mm] pv and feed electricity to a piece of copper and one piece of silver [ouma's never used sterling spoon tucked away somewhere at last found its mission on earth] inside the water about 100mm apart, about 500mm from the bottom. ionization will take place with copper and silver ions [positive] killing of bacteria, viruses [take note not virii!] and slime/algea.

i have been using rainwater like this from a tank for about seven years and i regularly forget the bleach, in other words the ionization does the job, and the water is still clear and good tasting. and take note, i have never cleaned the tank! so you will survive.

give it a try, its the cheapest and most effective way - and the little bit of bird poo from the roof adds extra minerals :D [after the sun has sterilized it].

the WHO states that for potable water sanitation:

the free residual chlorine concentration must be at least 0.5 mg/litre

so take a swimming pool chloride test unit to make sure this is the case if you really want to be on the safe side

http://www.who.int/water_sanitation_health/water-quality/guidelines/drinking-water-guidelines-publications/en/

Edited by gabriel
xtra data

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