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.”
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.”