Australian energy supplies

Electricity supplies in South Australia no longer depend on 'base load' generation with that being replaced by synchronous condensers, which provide “system strength” and other services without burning fuel. That means SA was able to generate its entire electricity demand from wind and solar alone for nearly four days continuously (i.e. day and night) in late November. With more renewable electricity infrastructure currently under construction and even more in planning, 100% solar and wind will become be the normal circumstance for SA with Australia's already lowest wholesale electricity prices to drop even further.

100 Per Cent Of SA Demand Met By Just Wind And Solar Over A 93 Hour Period
https://reneweconomy.com.au/solar-re...ecords-tumble/

The South Australian government target is for wind and solar to generate >500% of current local grid demand by 2050, and likely to be achieved because wind and solar infrastructure is cheap and once built the energy is free. The excess capacity means there will never be an undersupply of electricity and the excess can be exported and/or used for creating other forms of stored energy, such as hydrogen which can then be used to replace fossil fuel for forms of transportation where electrification isn't practical.

From the Sydney Morning Herald today:

South Australia sourced an average of just over 100 per cent of the electricity it needed from renewable power for 6½ days leading up to December 29 last year – a record for the state and perhaps for comparable energy grids around the world. The state’s previous record was just over three days, says Geoff Eldridge, an energy analyst who runs the website NEMlog.com.au, which tracks the operations of the National Energy Market covering Australia’s east-coast states and South Australia.




The Hornsdale Power Reservation in South Australia, where tech firm Tesla has installed a huge battery.

His analysis shows that for the six days identified, the state produced on average 101 per cent of the energy it needed from wind, rooftop solar and solar farms, with just a fraction of the energy the state used being drawn from gas, in order to keep the grid stable. At times during the period, slightly less renewable energy was available and at other times renewable capacity was higher than needed, he says. Bruce Mountain, director of the Victoria Energy Policy Centre, said he believed that aside from some small island grids such as those in Hawaii and Tasmania, it was likely that South Australia’s six-day run on renewables was a record for a grid supporting an advanced economy.

During the unprecedented 156-hour renewable run, the share of wind in total energy supplied averaged 64.4 per cent, while rooftop solar averaged 29.5 per cent and utility-scale solar averaged 6.2 per cent, clean energy website RenewEconomy.com.au reported, using Mr Eldridge’s data.

it is impressive and the way forward more places will be doing it.

I did have a chuckle at this bit:

with just a fraction of the energy the state used being drawn from gas

but don't let the title of " a week of 100% renewable power" get in the way of the truth, that there was still a fossil fuel source pumping into the grid and that it was just an average 100% renewable

Originally Posted by havabeer

it is impressive and the way forward more places will be doing it.

I did have a chuckle at this bit:


but don't let the title of " a week of 100% renewable power" get in the way of the truth, that there was still a fossil fuel source pumping into the grid and that it was just an average 100% renewable

The gas fuel supplied energy was used to keep the grid stable. IE correct voltage and frequency. A larger battery or a mechanical means of stabilising the grid would eliminate the need for gas. Note that it may be cheaper to use gas.


“His analysis shows that for the six days identified, the state produced on average 101 per cent of the energy it needed from wind, rooftop solar and solar farms, with just a fraction of the energy the state used being drawn from gas, in order to keep the grid stable.”

Originally Posted by phild01

What fraction though!?

Thought exercise.
I don't know what the faction is but it does not change the fact that SA for 6 days was powered by renewables.
Let us assume that in order to keep the SA grid stable, 10% (it does not matter what % we assume for the following argument) of the load has to be generated by gas generators. So if 100% of the load is being supplied by renewables and 10% by gas then SA will export the 10% excess to Victoria. SA keeps the “green” energy and exports the gas generated energy to Victoria. Victoria then can reduce the energy they are generating by the same amount that they are importing, thereby reducing their gas/coal consumption by the same amount that SA is consuming.
So we have the situation that SA generates all its electricity via renewables and no extra electricity is gas/coal generated within Australia as a whole.

UBD is correct. In effect the net generation consumed from fossil sources was 0% because the rest of the Australian Energy Market was being used as a 'battery' to mop up excess renewables and replace that electricity when there was a renewable shortfall. Obviously this will not work on a nationwide basis without either a lot more storage or, much more more likely because it is so cheap, a lot more renewable generation capacity combined with the ability to throttle output to prevent oversupply.

Unlike trying to limit output from nuclear and/or fossil energy boiling water steam turbine electricity generators which causes all sorts of problems for the generation plant, there is essentially no downside to feathering a wind turbine or reducing the output current of PV panels. In the first instance all that happens is that the wind going past the turbine isn't slowed as much, in the second the PV panel gets a little hotter and settles on a slightly higher panel temperature where reradiated heat matches the insolation less the lower electrical energy harvested.

Originally Posted by r3nov8or

One of the KI places might be John2b's
https://southaustralia.com/travel-bl...outh-australia

Not mine, and there are many more on Kangaroo Island than this list. We went off grid for economic and supply security reasons.

Today's news papers report there are significant wholesale price increases from 64% in SA up to 284% rise in Queensland on last year's prices, due to the rise in coal costs.



https://indaily.com.au/news/2022/04/...-prices-surge/

South Australia has been effectively powered by green energy for a week, with one expert predicting it could extend to a month by early next year.

From December 12 to 19, National Energy Market data showed wind and solar contributed on average 103.5 per cent towards the state's energy demand.
No coal was used during the period, but gas accounted for 5.9 per cent of electricity when renewable sources were not enough to power the state at points at night. The state's connection to the national electricity grid saw it import three per cent of its net energy demand.
The average cost of a megawatt hour dropped to -$26.35.
It's understood to be a world-first achievement for a jurisdiction of its size.

https://www.abc.net.au/news/2022-12-...n-sa/101788694

(BTW sorry to all the naysayers here, but it seems I was correct when I posted this #152 a year ago.)

Solar panels that work overnight? They're under development.

A consequence of the first law of thermodynamics, AKA the law of conservation of energy, means that the same amount of energy radiates away from the Earth overnight as arrives during the sunlight hours.

Solar photovoltaic panels convert the incoming electromagnetic radiation of UV, visible light and near IR (short wavelength infrared) waves into electricity. Earth's outgoing radiation is in the form of far IR (long wavelength infrared) electromagnetic radiation, so it stands to reason that with the right semiconductor materials it should be possible to capture the outgoing (nighttime) radiation with a photovoltaic panel. Turns out it is possible:

Night-time Photovoltaic cells

"No-light" PVs have only been under development for ~2-3 years. Not that long ago when solar PVs were introduced on watches and camera light meters they were around ~1% conversion efficiency and >100 times today's price.

A direct comparison for the output per m2 of light and dark PVs is not really important. The demand for electricity at night is never going to be as high as daytime, plus waste heat sources, such as cooling water from fossil or nuclear powered steam driven turbine electricity stations or other industrial processes can be used as the heat source giving substantial gains in efficiency and reduction in size of array needed.