When we think of renewable energy, it's easy to picture spinning wind turbines or rooftop solar panels. But what about bioenergy?

While wind and solar are now well established - in South Australia wind now supplies 33% of the state's power generation, while nationwide there are more than 1.3 million roofs now sporting solar panels - bioenergy has nowhere near the same reach or profile in Australia as it does in many other parts of the world.

Modern bioenergy is not simply about burning wood to provide heat, or using crop-based oils, sugars and starches for ethanol and biodiesel. The range of available biomass sources now includes municipal waste, forest slash, invasive weeds and cereal straw, and they are being used to make products like biogas, green electricity and jet fuel.

CSIRO research has previously shown that bioenergy could contribute substantially both to Australia's electricity generation (up to 20% in 2030), and to its liquid fuel needs (30-40% by 2020). If used at this scale, emissions in both of these sectors would drop significantly.

Slow out of the blocks

There are many reasons why bioenergy's huge potential has not yet been realised: economics, sustainability concerns, logistics, the bewildering array of options, and investors' wariness of new technologies.

From one perspective, different renewable energies like wind, solar and bioenergy are in competition with each other and need to be compared on the basis of their economic, environmental and social implications. If the full suite of new energy technology is added to the equation, this comparison becomes even more complex.

Yet recent research has shown that rather than being competing alternatives, different renewable energy solutions could complement one another. One example is hybrid bioenergy-solar systems, in which the solar output is supported by biomass burning, making the energy generation process more efficient and reducing the need for the solar energy to be stored in order to smooth out supply.

On top of the uncertainty about all these possible permutations, there are also the usual business and investment concerns around new technology in new markets. Add them together and you start to see why progress can be slow without clear policy support.

In the transport sector, bioenergy could help reduce fossil fuel use in areas that, for logistical reasons, can't embrace existing sustainable options such as electric vehicles. Aviation, agriculture, mining and shipping will all have to rely on liquid fuels in the short-to-medium term, and biofuels could offer an alternative that has lower in carbon impacts and particulate pollution.

New technologies mean that these fuels can now be made from non-food sources such as wood and straw. These fuels are not complementary liquids like ethanol which can be used in "blends"; rather, they are functionally equivalent fuels which are indistinguishable from fossil counterparts.

These fuels can be used as straight replacements for diesel, petrol and even aviation fuel. The global aviation industry including such companies as Airbus, Boeing and Virgin Airlines have been developing and trialling these fuels, and some of them already meet the very high requirements for performance and safety in aircraft.

Biomass burning is big elsewhere

In contrast to the limited recognition of bioenergy in Australia, biomass is playing a key role in meeting the European Union's sustainable energy targets, and in providing energy independence to the US military in terms of both electricity and liquid fuels.

Bioenergy offers opportunities not just for improved fuel self-sufficiency and emissions reductions, but also offers regional benefits of jobs, small business opportunities, diversification of incomes and risk management for farmers, and landscape renewal through actively managing the woody resources needed to make the fuels.

The question for Australia is: how can we take advantage of these opportunities? The Renewable Energy Target (RET) scheme creates a mandate for uptake of sustainable energy in the electricity sector, with its target of 41 gigawatt hours of power from renewable sources in 2020.

The RET has been very effective in stimulating rapid expansion of generating capacity, especially wind. But there has been little uptake of bioenergy, and the current uncertainty over the scheme's future could reduce these prospects still further.

Australia needs to invest in demonstration and development of the most promising bioenergy options and their supply chains, to accelerate the learning curve and drive down costs. It is critical that the RET be maintained, as this provides the certainty to business that allows investment. Ideally the RET should also be accompanied by a comprehensive climate change policy that drives improvements in energy efficiency.

Should bioenergy (and other renewables) receive such support, or should they instead be expected to stand or fall on their own economic merits? Groups like the Climate Institute have recently attempted to quantify the direct and indirect financial support that the very mature and established fossil energy industry continues to receive from the government.

In contrast, the emerging bioenergy industry does not receive the same level of support. For more than a decade, government policies have acted to reduce the limited financial resources available for this sector.

Improved support for research and development, and a more level playing field for renewable fuels in comparison with fossil fuels, would go a long way towards allowing Australia to join much of the rest of the world in benefiting from bioenergy.

Mark Brown receives funding from Australian plantation and forest management companies, Forest and Wood Products Australia, Australian Academy of Science and Bioenergy Australia. He is affiliated with Institute of Foresters Australia, International Journal of Forest Engineering, EU-FP7-Infres biomass supply chain mobilization, National Center for Future Forest Industries, Forest Industries Research Centre-USC and Forest Products Society Interantional Nominating Committee.

Annette Cowie receives funding from IEA Bioenergy, United Nations Environment Program, Bioenergy Australia, the CFI Methodology Development Grants Program and the Filling the Research Gap program. She is affiliated with the Australian Soil Science Society, the Australian and New Zealand Biochar Researcher's Network and the International Biochar Initiative.This article was originally published on The Conversation. Read the original article.