|Photovoltaics: incoming light from the|
sun converts to electricity
What is the quickest way to add a gigawatt of capacity to the South African grid?
Small-scale solar power on homes, institutions and business.
I am talking here about making electricity from the sun, not heating water. That is another whole issue.
Photovoltaic panels or PV for short produce electricity as long as the sun is shining, Modern PV systems even produce some electricity in cloudy weather.
A single panel is generally about 300W – so how do we multiply that to 1GW – a million watts? That would take about 3.3-million solar panels. This is how we can get there:
- 1 million single panels on RDP houses – in total 300MW
- 4 panels on half a million homes (totalling for each 1.2kW) – in total 600MW
- 50 panels on 5000 businesses (totalling for each 15kW) – in total 45MW
- 100 panels on 2000 public institutions (totalling for each 30kW) – in total 60MW
Where would you get those work crews? See my article Eskom – Restructure or Destructure?
This solar power will not all be available at once. None of it will be available at night and output reduces radically under cloud. If it is widely spread out of the country, a substantial fraction will be available most of the time – cloud cover shifts around the country.
And this is just a start – once this first phase is installed, there is no reason not to gradually spread it out to all RDP houses and all homes, businesses and institutions that can afford it.
How can it be paid for?
The poor should receive it free on RDP houses, with some of the cost recovered from power generated. Just as an RDP house has to be occupied for 8 years before ownership transfers, there can be a transfer phase when the solar power unit is generating electricity partially to recover its own cost and to cover the cost of the free allowance of electricity for the poor. Eventually it should be fully paid off.
For private premises, the payback time is relatively short – about 6 years. The ability to feed excess power into the grid makes this a great investment. And that is where reform is needed. Municipalities are reluctant to encourage solar power because it cuts into their profit on selling electricity. The remedy is simple: a grid-connect fee calculated to be equivalent to the amount the municipality would have earned as their share off the electricity cost had they sold Eskom power. If done right this can be revenue-neutral for municipalities while reducing their dependence on Eskom.
Without the ability to feed into the grid, solar power is only useful for cases where much of your power usage is in daylight hours or if you use batteries to store power for use at night. Batteries are expensive and limit the usefulness of solar to backup systems or to those who have to live off grid.