Before everyone screams conspiracy and money down the drain there is method behind the power ships. Solar and storage are just not a realistically viable alternative. Hang on to those pitchforks for a second, let me explain the reasoning.
- The approximately R20 billion a year includes all costs to Eskom. This translates to +-12,100,000,000 kWh @ R1.65/kWh that Eskom can sell to municipalities/direct customers. So the costs are passed on to the customers who actually use the power.
- Solar at best will provide 20% capacity factor, i.e. 20% of the nominal installed capacity over a whole day because it's sunshine dependent.
- So a 1220 MW power ship can output 1220 MW * 24 hours = 29 280 MWh/day
- A similar 1220 MW solar plant can only do 1220 MW * 24 * 20% (at best) = 5 856 MWh/day
- To generate the same amount of energy you would need a solar farm 5x as large, however this power would only be available during the day....because of the sun...
- To make it available at night you would have to install storage. Currently the price is approx. $500/kWh for a commissioned commercial battery system. Let's say Eskom would get a super sweet deal for $400/kWh. To make that extra 29 280 - 5 856 MWh = 23 424 MWh (23,424,000 kWh) available during the night would cost 23 424 000 kWh * $400/kWh = $9 369 600 000...approx. R136 000 000 000.
- But the solar system still needs to be purchased so let's say it costs R10 000/kWp...meaning 1220 MW * 5 (see nr. 3) = 6 100 MW = 6 100 000 kW --> 6 100 000 kWp * R10 000/kWp = R61 000 000 000
- So on paper the upfront costs for Eskom would be R136 000 000 000 + 61 000 000 000 = R197 000 000 000....you would say well that's like R3bn cheaper than the power ship deal...but...
- You're forgetting about maintenance costs over the lifetime of the systm
- The batteries would inevitably have to be replaced at some point during the next 20 years and with a system so large there would inevitably be component failure over the 20 year lifetime. You would require at least 160 million solar panels to put things into perspective...
So it it cheaper? Probably not.
Does Eskom have R200bn today to spend on installing solar + storage? No they don't.
Does it make sense to buy power from power ships and outsource all maintenance and procurement activities for fuel and just pay a per kilowatt hour charge to reduce the strain on the gird? Yes it does.
There is method behind the supposed madness...
Edit: The power ships will only add approximately 3% to the grid's capacity so the risk of a price doubling etc. is not realistic.