Buy water tanks, rainwater harvesting , greywater systems

Aquarista is the leader in Greywater garden irrigation and Rainwater Harvesting systems in South Africa.

Contact Aquarista.

Water and energy a thirsty business

water and energy, evapouration in water scarce countryAny economy needs a number of ingredients for growth. Of these, water, energy and food are key. But this century has been characterised by crises in all three of these areas. In SA, the water and energy sectors are facing severe constraints, which will affect growth.

Around 98% of the water resources in SA have already been developed and allocated. Agriculture soaks up 62% of this but contributes only 3% to GDP; the economic impact of a unit of water used is low compared with other sectors.

The energy sector is also a thirsty industry and should perhaps have higher priority than agriculture (assuming an open economy and the ability to import food).

All SA’s coal-fired power stations require significant amounts of water. A 5000MW plant (about the size of Medupi) will use 60m m³ of water every year with wet cooling (that’s 2000l a second), but only 6m m ³ with dry cooling technology.

No wet cooling plants have been built since the 1970s , but some of the old ones are still operating .

Added pressure on the water supply will come from a pending compulsory flue gas desulphuring process (which reduces CO ² emissions). This water-intensive process will add 8m m³ of water a year to Eskom’s demand.

By 2030, the plan is that SA will have moved away from coal dependence to solar and nuclear power. Nuclear plants can use sea water (if located appropriately), so their demand for fresh water is minimal. A 5000MW concentrated solar power station, however, would need 15m m³ a year.

Eskom is looking at internal innovations to save water as well as the possibility of using polluted mine water, which could save up to 6% in five years. “We are working with the mines to implement treatment plants for the water to help them to treat it to our quality requirements,” says Eskom procurement officer Nandha Govender.

Big business also realises the strategic importance of a secure water supply.

Sasol, for example, requires 90m m³ a year of water at its Secunda operations and 22m m³ a year at Sasolburg . It receives water from the Vaal river system. But growing demand from domestic and agricultural users, pipe leakages and unlawful irrigation all place stress on the system. Climate change adds further risk to the country’s river systems .

Many of Eskom’s power stations also depend on the Vaal River system .

“Sasol is co-operating closely with Eskom, the department of water affairs and other participants to address the water availability, quality and supply risks in the Vaal system,” says Sasol environmental adviser Martin Ginster.

Re-use of water, effluent treatment, and water efficiency are vital parts of Sasol’s operational health.

As demand for water increases, SA will either have to re-use and/or desalinate water. But there are always financial constraints. This means SA will have to prioritise the use of its precious water resources, and this will involve tradeoffs. “Eventually we may find it’s better to buy out allocation rights,” says Johan van Rooyen, director of national water resource planning at the department of energy.

In SA, agriculture — the water guzzler — would perhaps be the first to find its supply restricted . Van Rooyen says opportunities exist for rain-fed crops to be grown and traded across the Southern African region, minimising irrigation .

Speaking at the SA Water & Energy Forum in Sandton on Monday, Prof Tony Allan, Stockholm Water Prize Laureate, said countries would have to start trading “virtual water” to reduce local usage. For example, by not producing grain locally, and rather importing it, a country would save 1000m³ of water per ton of grain imported.

“It’s not the water that’s traded, it’s the commodity, but the amelioration that comes to water-scarce countries is evident,” he says .

The “saved” water would then be used for more productive purposes, where the contribution to GDP would be higher per unit of water. In SA this could mean that the agriculture industry may struggle to secure the water it needs.

In a resource-scarce environment there is no choice but to allocate water to points of efficiency.

Resource efficiency, across sectors , will therefore become a key factor in doing business and allocation decision processes.

Source: FM

Today I only have a question for all my fellow South Africans. “Where will we get all our water from if we do no start water conservation practices today?

Water Rhapsody has solutions, are you prepared to face the harsh reality and embrace a solution?

Leave a Reply

You can use these HTML tags

<a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>