Electricity and water crises now a reality

James Green, SESSA Solar Water Heating Chair

Water saving measures has been largely ignored in South Africa. In much the same way as cheap electricity has lulled the public into a false sense of security, and consumer renewables in form of solar water heaters to replace electricity in heating water have been ignored, the current drought may force consumers both domestic and business to rethink water as a free or cheap resource.

Water losses at municipal levels of 30% (typical) to good management at 15% (Cape Town) are of course a huge area of concern, but what are the water losses (if any) at home, and what can be done to become more sustainable in water management.

The point was brought home to me personally when analyzing my water consumption at home. How could 4 people be using 4,000 – 6,000 litres per day?

Turning off the stop cocks at the two points into the home, and watching the water meter continuing to spin slowly was a shock. After much investigation we determined there must be a leak through one of the old galvanized pipes, running under the soil in the garden, and indeed being an old house before the property was subdivided a second leak in a spur pipe in our neighbour’s garden.

After some rapid re-plumbing of the mains water into the house, and additional testing, the meter not only stopped turning, but the daily water consumption has reduced to 1,200 -1,500 litres per day. Potable water has been expensively wasted through an “out of sight out of mind”, unknown problem.

The convenience of mains municipal water is forgotten in day-to-day life, but when water has to be carried to refill a lavatory cistern, approximately 9 litres, (we had no water during the re-plumbing exercise), it reminds one of the huge value of a reliable clean water supply, sadly not enjoyed by many millions across Africa.

A different example was when visiting a government owned building  (desperately in need of maintenance) earlier in the year, where a broken pipe was spewing water into a pit at a rate of about 1 bath every 20 seconds. It had been doing so for over 10 days. The reality is that unless one is paying for the resource, either electricity or water, it is no different to seeing a burst water main in the road. 

So what can the consumer do? 

Check your Water Meter

Firstly check their water meter. Turn off all stopcocks (after the meter) into the property and check whether the meter is turning. 

  • If it is, further investigation is required. 
  • Repair the leak if required.
  • Check dripping taps and lavatory flushing mechanisms.
  • As a guideline a 4 person home should be using between 800 litres and 1,200 litres per day (ignoring watering the garden).

Move to dual flush lavatory mechanisms 

  • Approx. 10,000 litres per person per annum can be saved by using the half flush for number 1’s and the full flush for number 2’s. 
  • A home of 4 would save approximately 40,000 litres per annum, or to put it in context, a small swimming pool in wasted water annually.
  • From an investment perspective, the Return on Investment is incredible, paying for itself hundreds of times over in a few years.
  • For example, in RDP homes the difference in the capital cost of fitting a (locally manufactured) dual flush mechanism rather than a full flush is less than R50 per home, but the water savings are likely to be in excess of 50,000 litres per home per annum.

Move to a decentralized biological wastewater recycling plant 

This will take black water (includes No 2’s) and grey water (everything else) and the system will return clean reusable water that can be used for literally everything other than drinking (flushing lavatories, crop and garden irrigation, filling pools, washing machines and car washing etc). Depending on the level of filtration 100% of the water can be reused, resulting in effective savings of 50% of fresh water consumption. 

  • The potential payback (Return on Investment) is as little as 3-4 years or less if several houses join together (4 or more)
  • Generally more suitable for complexes (RDP or estates), business, schools, hotels, hospitals and restaurants or anywhere where there are a large number of occupants, the potential water and financial savings are huge. Additional benefits include no sewerage piping or infrastructure. 

Rainwater harvesting 

Where rainfall is collected and cleaned and stored in tanks, for use either in the garden or for use in lavatories. 

  • The payback again can be as little as 3 years.
  • In Bermuda all water used is rainwater (no boreholes) and goldfish were used to keep the mosquitos at bay!

Water is a valuable commodity, which is taken for granted, until that time when it is no longer readily available. In South Africa the impending problem is increasing because of the difficulty in cleaning subterranean aquifers. Acid mine drainage in the Johannesburg area is such an example. 

In comparison in Harare where the water has been under pressure for years, many consumers have been forced to put in boreholes that put increasing pressures on underground supplies, or resort to having (expensive) potable water delivered in trucks. A similar story exists in Nairobi.  

In the Western Cape the water shortages are forcing consideration of large scale desalination plants, much in the same way as has been installed in Sydney. 

Sustainable water use is essential particularly at times when climate change is affecting weather patterns. El Nino in 2015 has already ended the drought in California, but in Southern Africa, we are suffering the opposite. The Zambezi floodplains have been pitifully low for the last 2 years, and the same is predicted for 2015/16 season. At November 2015 the water going over the Victoria Falls is far less than usual, and Lake Kariba further downstream is at historic lows. One huge consequence is hydro electricity cut backs, with electricity load shedding in Zimbabwe for up to 20 hours a day, and 8 hours a day in Zambia. For South Africa reductions in hydro output may be around the corner with Cahora Bassa not being fed with the necessary water flows.

Human nature is to ignore the problem until it is too late. The recent reduction in electricity load shedding in South Africa has resulted in falls of sales of generators and home Solar PV systems, but the reality is that the problems that exist have not gone away. South Africa faces a huge power supply demand challenge, and it will endure for years to come. 

The consumer can contribute by removing power off the grid, and reducing carbon emissions, by going solar both with solar water heaters and solar Photo Voltaic systems. 

It may take the water to be turned off, before homes and businesses realize we have an impending crisis, (at the time of writing 2 hospitals in Johannesburg have no water) but the realities are that climate change will force a realignment of priorities of what we have taken for granted to be luxuries.

Water conservation and sustainability along with saving electricity should be at the top of the list. 

Without fresh clean water there can be no electricity, no agriculture, no industry and no life.