Yesterday, we brought you a roundup of how geothermal and bioenergy are helping populate the bustling world of alternative energy sources. Today Crikey continues this exploration with the help of the Climate Council and climate solutions analyst Petra Stock to see what else is going on in Australia beyond the obvious sources of solar and hydro.
Solar thermal plants
How does it work: Plants vary according to resource and technology, but involve concentrating sunlight, generally off mirrors, to heat a substance, either liquid or salt, that can then be used to power steam turbines.
Australian status: We only have one operating plant, currently in conjunction with the Liddell coal-powered station in New South Wales, after CS Energy pulled the plug on a 44MW “solar booster” to its coal-powered Kogan Creek, Queensland power station in 2016. Both of these are set to be completely outshone (!) by SolarReserve’s recently announced plant in Port Augusta, South Australia. Announced in August last year, the project will offer 150MW of dispatchable solar power, supply 100% of the SA government’s energy needs from 2020, and — barring approval for a $110 million federal loan — will begin construction mid-2018.
Why is it interesting: Offers a form of both generation and storage that answers the always popular “sun doesn’t always shine” criticism of solar. Stock says the trade-off for a 24/7 source of solar power is that, despite advances in commercialisation, thermal plants are still pricier than panels. “[Port Augusta] was $78 per megawatt hour, so it’s more expensive than solar panels or a wind plant, but still cheaper than building a new coal or gas plant.” She also notes that there is a pre-existing plant in Port Augusta, SunDrop Farms, that uses solar energy to grow tomatoes and desalinate water rather than generate electricity. Science!
Offshore wind farms
How does it work: Like onshore wind farms, but offshore. There is not that much more to it.
Australian status: Nothing currently operating, as we already have enough onshore potential to power a country 12 times our size thank you very much, but plans for a massive 2GW farm off the south coast of Gippsland have gained pace after the Melbourne-based developer, Offshore Energy, announced a partnership with Danish company Copenhagen Infrastructure Partners in December. The “Star of the South” project could power 1.2 million homes and is strategically located near existing transmission infrastructure in the Latrobe Valley, home of the recently closed Hazelwood coal-powered energy plant.
Why is it interesting: Popular in congested countries which have basically run out of land. “That’s probably why countries like the UK, China and US, are starting to build those offshore wind energy plants,” Stock says. “Because they’ve got those higher levels of population and may have maximised where they can put their solar panels and their onshore wind farms.”
Ocean power
How does it work: Most forms of ocean power refer to turbine systems harnessing the relatively enormous kinetic potential offered by tides, waves and currents, with some more complicated systems harnessing salinity and temperatures. Sadly, none of these confer actual power over the oceans.
Australian status: Small projects but nothing commercial. Global research into oceanic power generation only really started in 2003, with the UK currently leading the world in commercialisation but Scotland only opening the first large-scale tidal energy farm as recently as 2016. However Australia’s long and deep coastline has been flagged as a prime resource for the technology, and wave projects such as “CETO 5”, established for a navy base near Perth in 2015, have offered breakthroughs in energy generation, grid-connectivity, and desalination.
Why is it interesting: Offers similar advantages to offshore wind farms, the predictability of tides, and finally — and this one’s for you Joe Hockey — a unique, submerged kind of visual beauty. “Often those projects are quite visually stunning,” Stock says, pointing to photos of CETO as an example. “It’s kind of a series of submerged buoys that sort of look like giant robot jellyfish underwater.”
Offshore wind power is the winner no NIMBY syndrome
Re thermal storage, in South Australia there is serious development of a Thermal Energy Storage System (TESS) using silicon – touted at a fraction the cost of Tesla batteries & not requiring replacement.
If you have a roof, you can haz pumped hydro, to complement your PhV.
You need a big roof tank to do that. And another at ground level or, preferably, below.
If you had a 1m deep reservoir on top of your house, with a floor area of 200m² and an effective height of 5m (lower reservoir below ground level) your storage would be about 2.7kWh. A fraction of what a decent PV array could do in a day (my 5kW system gets about 25-27kWh on a sunny summer’s day). Meanwhile, you have a 200t water tank on top of your house that needs supporting!
Every one of these whimsical schemes requires fossil-fired backup. Even when its believers can claim to have a token of storage installed (pending mythical investment by the taxpayer), it too will run out one nasty night and require full power from a fossil-fired grid.
But all fossil fuels must be stamped out in the decades ahead. And without fast-responding backup, these schemes are useless. They will stand unused on our skylines, a taunting memorial to the moral cowardice of the generation that built them.
“Every one of these whimsical schemes requires fossil-fired backup.”
No, they really don’t.
Battery backup is fast responding.
Hydro (conventional and pumped) is fast responding.
Gas open cycle is not as fast as the above. Combined cycle gas is slower again.
Coal is not very fast responding. Not real sure about nuclear.
“Even when its believers can claim to have a token of storage installed (pending mythical investment by the taxpayer), it too will run out one nasty night and require full power from a fossil-fired grid.”
So, there has to be days where there is no wind, no sun (even on a cloudy, rainy day, PV solar generates some power), the hydro reservoirs are all at the bottom – all over the eastern states of Australia.
Also, the night generally has lower demand than the day, the peak demand during the year is in the late afternoon/evening on a hot summer’s day. Roughly the same time as solar’s peak generating time.
Hi Wayne. Batteries can respond fast, yes, but for how long? Any storage runs out eventually. Even the biggest battery in the world (120 MWh) can only supply SA (1200 MW) for one-tenth of an hour.
Enough storage to cover rare, say once-in-five-years events will never get budget priority. Instead, local schemes that claim to have enough storage to be 100% RE, would prudently stay connected to the grid while hoping that it would not notice their absence. For that event when their storage runs out, they then switch on and burden the grid when it is already at full capacity. If such a grid can be nuclear powered, why waste money on renewable energy?
Because renewable energy is cheaper.
Cheaper to install, cheaper to run, less maintenance and less environmental impact.
The SA battery farm is rated at ~100MW, so can supply ~1 hours worth of power.
Only some homes and businesses would be disconnected from the grid. The utility scale renewable energy generators are on the grid.
If “the SA battery farm is rated at ~100MW”, then it can only backup 100 MW of wind generation. That’s a small fraction of SA consumption of 1200 MW. That leaves the majority of 1200 MW to be backed up by the connection to the rest of the Australian grid. As a result, most of the electricity consumed in South Australia is generated by local gas turbines and the brown coal burners in Victoria, next door.
At this time.
I should say that extra storage is being planned for the next few years, including pumped hydro.
And South Australia doesn’t have enough renewable energy to cover its needs – yet.
Any increases in storage are more symbolic than substantive. Including its necessary storage (and powerlines and pipelines) makes 100% renewables just too extensive and too expensive. By comparison, nuclear energy is cheaper. Cheaper to install, cheaper to run, less maintenance and less environmental impact. (– to misquote a wise man from somewhere upthread 🙂
Nuclear power is not cheap,
It is more expensive to install than coal fired power stations.
I saw a video a little while ago that explained that renewable energy costs have come down because they are largely manufacturing costs, while fossil fuel power stations have a large operating cost component. Same could be said of nuclear power, I would think.
You’re quite right. Cost of wind turbines has tumbled with mass production in China. Cost of gas backup is low too, because the gas turbines are factory made and practically wheeled into place, ready to fire up, arguably less than 2 $/W of capacity.
Nuclear generators have yet to be mass produced. Current front runner design (being scrutinised now) is the NuScale, but it is a very conservative passive design with an initial cost of 5 $/W. Other designs are cheaper, but coming later.
Nuclear pulls ahead on low maintence, low fuel cost, long life and, above all, zero carbon emissions.