Tag Archives: waste

Aquaponics and the Meaning of Life

With the first Winter rains now falling in the Western Cape of South Africa and the grapevines almost bare of their Summer plumage, ones thoughts turn to more philosophical directions. I enjoy Winter in the Cape. It offers a time for introspection; re-visiting the successes and failures of the previous growing season and planning for what lies ahead.

Aquaponics (AP) really is a scale model of the workings of the earth and provides a great platform to explain how everything hangs together. I have taken many school groups through my various AP builds over the years and I have found it extremely heartening to see the “light-bulb” moment as a child suddenly sees the point of it all. When he/she realizes that every system (whether organic or mechanical) works exactly the same and that it is infinitely scalable, the impact is huge.

Nature has no waste. Every output from one system is an input for another. Our artificially created, urban living areas “appear” to generate massive waste and seem, on the face of it, to be unbalanced, but in reality nature mops up the waste over time and uses it as an input in another system. What we must realize is that it doesn’t all happen immediately and it may be many, many years before the next system even needs the output from the earlier system.

There are many examples of this. Gold mining is one. The goldfields of South Africa and other gold producing countries are littered with “mine dumps”. These discarded mountains of earth are the by-product of the mining and extraction process. At the time, the cost and availability of technology and the price of gold didn’t make it feasible to process these dumps any further. Now, many years later, it provides a lucrative new source of gold which is extracted from these “dumps”.

Landfills are another example. I predict that in the future these hidden dumps of a civilizations waste will power cities with easily-extractable methane and the solid matter recycled in a multitude of ways.

There is no waste in the long-term.

AP has often been described as a “closed-loop” system; a perpetual motion, organic machine that, once in balance, will sustain itself indefinitely.  In theory this is true, but in practice it is not very long before some or other input is required, the most obvious being food for the fish. Another is an AP systems rapid depletion of iron and other trace elements needed in only small doses, but without which, the system comes crashing down.

The secret of AP and Life itself, is thus BALANCE. Balance is often not apparent in a snapshot, but if you look at the system, in whatever form, over a period of time, it seems to smooth out and settle into a balanced state.

Our lives, in a seemingly meaningless, headlong rush to the grave, also seem out of balance, but below the surface of this raging river is a calm, balanced, REASON for it all.  Sometimes we just have to step back, lift our eyes from our iPhones and other distracting gadgets and realize that this is all part of a bigger plan.

We are just so bogged down by detail and noise and confusion. To truly appreciate the meaning of it all, maybe we should just go out into our gardens and truly OBSERVE the miracle of nature, be it only in a tiny patch of green that we call our own.

Henry David Thoreau, the finest American philosopher who ever lived, said, “Our life is frittered away by detail.

Get out there and appreciate it.





Free, from the sun.

I wrote a blog entry some time back lamenting the waste of water in this country. The number of roofs without efficient gutters and collection tanks seemed such a waste.

Another real waste, especially in these times of “Eish its Eskom”, is solar energy. Every morning the sun rises in the East and every evening it sets in the West. It shines down on roads, buildings, grass, plants, people, cars and everything else “under the sun” and how much of this do we collect and use as an energy source? Very little.

It was thus heartening to read today, that electric geysers will have to incorporate solar heating by 2010 in all new houses in South Africa valued at over R750 000, or larger than 300 square metres.

This would also apply to commercial buildings, hostels, resorts and shopping centres, the department of minerals and energy told Parliament’s Portfolio Committee on Minerals and Energy. What good news for a change.

South Africa, with one of the highest average sunlight hours (9.5) a day in the world, would be foolish to ignore the potential of solar power. What is urgently needed now however, is a cheap and super-efficient solar panel invented right here in this country.

There are vast open (mainly desert) spaces in South Africa with massive areas that could be covered by solar panels and supplement our power grid with clean, renewable solar energy.

We get hot, so we we switch on an airconditioner, which uses valuable electricity to remove the heat from where we are and move it elsewhere (ie. a heat-exchanger). What a waste. This is valuable energy, on which we are expending scarce recources, to move somewhere else. Rather spend more money on better insulation and capture the solar energy before it heats up an area that we want to keep cool.

This was something that intrigued me about travel. Everyone seemed to be unhappy with where they were. That is, everyone wanted to be somewhere else. Why? Why are we unhappy with where we are? The same with solar energy. The Sahara desert bakes at 50 degrees. There is more than enough heat. In fact there is far too much heat. If we could just capture this heat (or energy) and move it efficiently to places that needed the heat (or energy to make heat), we would have solved the energy problem.

What we need is a Global Heat Exchanger (GHE).

Remember, you heard it first on Synaptoman.

Be Good.

It’s all going to waste

Since installing my tanks to collect rain water for my Aquaponics project, I have become very aware of the terrible waste all around us. I sit looking at a roof of about 300sq/m below me on the hill, with neat and clean gutters and downpipes channeling all of that rain water straight down the drain. What a waste. We have a crisis in this country with a growing and demanding population, and shrinking resources. We are struggling as a country to provide water, electricity and sanitation, and yet what are we doing in our own cities, towns and suburbs to address this problem? Nothing.

If we take the 300 sq/m roof as an example. It is North-facing ie. the roof runs from East to West and the pitch slopes down on the North and South sides. The sun is in the North (dughh) and our prevailing wind comes from the West.

If we covered the North side with solar panels, mounted wind-turbines along the top, and collected all of the water running off of the roof, I am sure that we could certainly make a substantial dent in the monthly water and electricity bill.

The problem is the initial cost, and until we can get this cost down, nobody is going to bother. It’s easier to just leave it to the Government/Municipality. And in 10 years time when the cost of water and electricity, as supplied by the authorities increases 10-fold? Then we’ll all moan and wring our hands and wish we had done something sooner.

When trying to justify alternative energy investments, I think we all fall into the trap of saying, “well if I spend this money now, it’ll take x years to recoup my cost.” Hogwash. Don’t use the current cost of the resource. Multiply the cost of water and electricity by 10 and THEN look how fast it pays for itself.

The same applies to fuel. Yes, a diesel, electric or hybrid car does cost a lot more, but just look at the graph of fuel prices. Just a few more years at this rate and suddenly the alternative energy car doesn’t seem so expensive after all.

We must have more sunny days in South Africa than most other countries in the world. We urgently need to harness this energy that’s going to waste. A massive push is needed to design a cheap local solar panel. Our rainfall in this country isn’t bad, but I really don’t think we all do enough to collect every drop.

If we could just regard this first stage as an “awareness” stage and then turn this awareness into action.

Food for thought?



Every drop is precious

Strip naked, open shower door, switch hot tap on, wait, scratch nuts, wait, check temperature of water with hand, wait, scratch bum, wait, check temperature of water with hand again, almost there, wait, yawn, check again, great, step inside.

Sounds familiar? Apart from having to stand naked on a freezing winter morning waiting for the water to run hot, have you ever considered how much cold water goes to waste every time you run a shower. What a waste. Surely there is an easier and less wasteful way to get the water to temperature. My shower is reasonably close to a geyser, but what about the bathroom far from the geyser? That hot water tap takes ages to run hot.

So I got thinking while having my shower this morning, and I present my invention for comment. I’m sure this problem has been solved a million times but I don’t know of a solution. Here is my idea.

When you switch any hot water tap in the house on it activates a timer. No water immediately comes out of the tap. The timer activates a non return valve (NRV) which send all of the cold water in the hot water pipes back into the cold line coming into the geyser. Another NRV stops this water from going back up the cold line. After a couple of seconds all of the cold water in the hot water line has been replaced by hot water from the geyser. The NRV switches off and hot water flows out of the taps. Here is a rough sketch.


All that is missing in the above sketch is possibly a valve on the shower side of the line to hold water from the taps until the timer switches the valve to the cold line off.  The timer and NRV#2 obviously has to be as close to the taps as possible to replace as much of the cold water with hot.  Maybe a timer and valve at each tap?

OK, now go and improve on it.

Very clean.


P.S. I was going to write about the Nationwide jet that lost an engine on take-off from Cape Town yesterday under the title “Only in Africa”, but I have decided to be more positive in my outlook for a while, but trust me, there was plenty of ammunition for me in that story.