Animal waste is part of a plethora of newer energy sources

Australia is in the middle of a renewables investment boom that, despite just constant disappointment and uncertainty at the federal level, will see the country reach our Renewable Energy Target earlier than predicted.

But while solar panels, wind turbines and hydropower are the most popular forms of renewable energy, the truth is Australia has much weirder stuff going on. Crikey talked with Climate Council energy and climate solutions analyst Petra Stock to see what else is going on in Australia.

Geothermal

How does it work: Systems that steal precious, precious heat from beneath the earth’s surface vary according to the state and temperature of the natural resource. For example “hot sedimentary aquifers” (HSA) use existing hot water or brine found in naturally occurring reservoirs; “enhanced geothermal systems” (EGS) create steam by pumping water through hot rocks 3-5 kilometers below the earth’s surface; and “direct use systems” skip the electricity phase altogether and directly pump hot/cold groundwater wherever it is needed.

Australian status: Early stages and rocky starts. While geothermal counts as a major resource for highly volcanic countries like Iceland and Kenya, projects are relatively uncommon in volcanically-boring Australia, a challenge historically compounded by the distance between remote geothermal project and customers. All the current action is happening in Queensland, with one HSA plant operating in Birdsville, another coming online in Winton Shire, and plants currently being explored or developed in Thargomindah, Quilpie, Normanton and Longreach.

Why is it interesting: As newer microgrid technologies encourage greater independence from existing grids, projects are becoming increasingly attractive to regional towns because they can provide 24/7 “baseload” electricity and incorporate existing infrastructure and resources. Stock points to Winton Shire’s application of existing water bores as an example of the town “making use of what infrastructure they have already; obviously building on that, but as a way of minimising the impact of that project.”

Bioenergy

How does it work: Transforms biomass, or biological waste, into electricity, heat, or liquid fuel. Again, the process is especially attractive to regional areas because the most popular forms of biomass account for agricultural waste, notably wood, animal waste, oil seeds and, according to ongoing research at the University of Melbourne, algae.

Australian status: Our number-one forgotten renewable, biomass provided roughly 1.5% of Australia’s power generation in 2016 and, at 8.6% of total renewable output, comes in fourth behind hydro (42.3%), wind (30.8%) and small scale solar PV (16%). Recent projects include Queensland’s Tableland Sugar Mill, which uses the most popular form of biomass, sugarcane waste or “bagasse”; Brooklyn, Victoria’s City Circle Waste Timber Gasification Plant, a timber-powered plant using crushing and recycling waste; and Queensland’s Darling Downs Fresh Eggs, which in 2015 became the first Australian business to be powered by chicken poo.

Why is it interesting: It is energy from actual waste, what more could you want? While conversion processes still release carbon dioxide, bioenergy counts as sustainable because the major source, plants, take carbon out of the atmosphere while growing and can be managed sustainably in relation to food and animal waste.

“The great thing about biomass is its usually using some sort of existing waste product,” Stock says, noting that the process is most often used in farms or related business such as Victoria’s Berrybank Piggery, which “has a plant that converts all that piggery waste into both electricity, to power their own operations, and also fertiliser.”

“I mean that’s great: they get cheaper electricity bills and this other useful product out of something that was otherwise a waste product.”

Read part two of Crikey’s list of alternative alternatives here.