In their last financial year Gauteng's metros lost a combined R7.9 billion worth of water and electricity, a Business Insider South Africa analysis of the annual financial statements published last week by the cities of Johannesburg, Tshwane and Ekurhuleni show.
R3.95 billion of those losses, also referred to as "non-revenue" water and electricity, were attributed to "non-technical" reasons – theft, billing mistakes, and other preventable losses.
Roughly the same amount of money was lost to technical reasons, some of which are inevitable in the normal operation of water and electricity networks.
In total, Gauteng's three metros lost R5.1 billion of electricity they bought but were not paid for in turn, and some R2.8 billion in water they bought, but never saw a cent for.
But not all technical losses were equal, a comparison of the technical losses show.
According to their audited numbers, the City of Tshwane lost 25.4% of all the water it bought for technical reasons. For Johannesburg that proportion was 18.3%, and in Ekurhuleni it was 15%.
There were also stark differences in the rates of theft and other preventable losses across Gauteng's big cities. Ekurhuleni recorded double the rate of non-technical water losses seen by Johannesburg and Tshwane – but had a far lower rate of non-technical electricity losses.
Here is how much money Johannesburg, Tshwane, and Ekurhuleni lost in water and electricity in their last financial years.
Expressed as a percentage of their bulk purchases of water and electricity, this is how much each of Gauteng's three metros lost in water and electricity, through both normal operation and theft.
Non-technical losses covers a range of reasons for not recording sales against water and electricity, including broken meters, illegal connections, and administrative errors.
For electricity technical losses of around 5% to 7% are considered reasonable in large networks, and around 9% non-technical losses are considered nearly inevitable.
Unlike electricity there are no inevitable losses due to electrical resistance and losses in transformers for water. But losses of between 18% and 20% are generally considered to be inevitable because at such levels the cost of water lost to leaks is less than the cost of fixing them.
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