Put simply, biofuels are energy sources made from living things, or the waste that living things produce. The concept and adoption of biofuels is nothing new; in the early 20th century car inventor Henry Ford originally designed the Model T car to run on ethanol, and large-scale biomass power plants, fed by woodchips or other plant or animal waste matter, generate electricity for thousands of people across the globe, including in the UK and US.
Due to the flexibility of bioenergy – it can be used to make heat, electricity or fuel, whereas wind and solar only make electrons for electricity – scientists are increasingly exploring different forms and uses for it.
Scientists at the Western Michigan University in the US are working on ways to use waterborne algal blooms from farm fertilizer runoff, which can destroy aquatic life and clog rivers and lakes, as feedstock for biofuel plants.
Researchers at KTH Royal Institute of Technology in Sweden and Harvard University in the US have developed “soft, highly robust” batteries from tree fibres that could be used to power everything from electric vehicles to clothes embedded with electronics.
And in 2013 engineering firm Arup unveiled the world’s first algae-powered house in Germany. The house has a bio-adaptive façade that uses live microalgae growing in glass louvres to generate renewable energy and provide shade at the same time.
Is algae-fuel a game-changer?
It’s not going to be the answer to the world’s energy solution but it can play a role
Many commercial-scale algae technologies are projected to continue to grow in the future. This includes anaerobic digestion systems, which produce biogas for use as gaseous boiler fuel or to feed into the natural gas grid, and commercialised wood pellets for heating and energy,
But how likely are prototype innovations, such as algae-power, to become common technologies in our everyday lives?
“In reality, what we have found is that it’s not going to be the answer to the world’s energy solution,” says Dr John B Millar from the chemistry department at Western Michigan University.
“But it can play a role, particularly in looking at transportation or solid fuel used for local energy sources.”
Millar is part of the research group at Western Michigan University that is looking at ways to use waterborne algal blooms from farm fertilizer runoff.
Although John insists that algae as a biofuel is, at the moment, not ready to play more than a ‘research role’ in solving the clean energy dilemma, he insists the potential for algae-power or algae-fuel is strong and diverse. In fact, the energy potential for algae compared to conventional biofuels, such as ethanol and maize, is between 5 and 12 times higher.
“There are some mono-cultures of algae that are being bred to basically exude oil as part of their metabolic process; they give off vegetable oil that can be harvested into a petroleum type of fuel to potentially power cars,” Miller says.
This type of oil-harvesting has to be done in a controlled facility because the culture of algae is genetically modified so it would pose a threat if allowed to enter the natural environment.
Senior research manager at the Energy and Environment Research Center in the US, Chad Wocken, writes in Biomass Magazine that unlike traditional oilseed crops, which produce 10 to 100 gallons of oil per acre, algae are mega oil producers capable of producing 1,000 to 5,000 gallons of oil per acre.
“Oil collected from algae looks very similar, chemically, to crop oils and can be converted to renewable fuel using existing technology. Algae also do not compete with food sources, can grow in non-potable and saline water on otherwise non-productive land, treat polluted waters and recycle carbon dioxide,” he adds.
Similar to how offshore oil and gas platforms exact fossil fuels in the open ocean, so could algae be “grown large-scale in mid-ocean, depending on environmental impact and an agreement between international bodies,” says Miller.
Extracting electricity from living organisms
Researchers are using bacteria to couple electrical cells to split water
There is also work being carried out that is looking at bio-electricity formation; electric potentials and currents produced by, or occurring within, living organisms.
“Researchers are using bacteria to couple electrical cells to split water,” says Miller, referring to the term used for a chemical reaction where water is split into oxygen and hydrogen. Efficient and economical water splitting would be a key technology component of a hydrogen economy.
An ‘artificial forest’ that can convert solar energy into chemical fuels has been developed by scientists at the Lawrence Berkeley National Laboratory. Mimicking photosynthesis, the artificial forest soaks up light and uses it to generate oxygen and hydrogen, two gases that can be used to power fuel cells. The process also facilitates solar water-splitting.
Researchers from Virginia Tech have also developed a new way to make hydrogen fuel cheaper and quicker than existing methods by making the fuel from the husks, cobs and stalks of corn, instead of using sugars that are costly to process.
Simple yet effective
Move to different a context and not all biofuel concepts have to be complicated to be effective. Some small-scale biofuels being used in developing countries right now are so impactful they are actually saving lives.
According to the World Health Organisation, every year over 4 million people die prematurely as a result of indoor air pollution, primarily the result of cooking on mud stoves with wood, and more than 50% of premature deaths among children under 5 are due to pneumonia caused by particulate matter and soot inhaled from household air pollution.
Grass-roots company Sustainable Green Fuel Enterprise (SGFE) in Cambodia has developed charbriquettes that come from organic matter – coconut husks and shells, rice processing waste – that would otherwise end up in local landfills, and which can be used as clean efficient fuel for home cookstoves, while also reducing deforestation.
Presently clean, and more importantly, cheap biofuel for cookstoves such as those made by SGFE only reach a small part of the developing world’s population. Rolled out across Africa and Asia, these simple yet effective biofuels could save millions of lives while reducing deforestation and waste headed to landfill.
More investment needed
Until there is significant carbon regulation worldwide I don’t see biofuels such as algae being strong at all
Although biofuels, such as hydrogen and ethanol for cars are already being deployed and used at a commercial scale in the west and BRIC nations – in the US biomass currently accounts for about 2% of energy production and about 10% of ethanol is used in much of the country’s gasoline – most of the projects mentioned in this article are still at the research stage. And due to a lack of investment, incentivising legislation and a lack infrastructure, the energy they produce will not likely find its way into our cars or homes any time soon.
The lack of consistent policy and regulatory frameworks “hinders investment in and expansion of bioenergy technologies, be they for heat, power/electricity or biofuels,” according to chief engineer at the National Renewable Energy Laboratory, James D McMillian.
Miller adds that it is very hard to get biomass/biofuel projects bankrolled in an environment of low-priced petroleum, effectively cheap gas and relatively cheap coal.
“Until there is significant carbon regulation worldwide I don’t see biofuels such as algae being strong at all,” he says.
“It really takes a willingness to recognise that we are not paying the true cost of petroleum because most fossil fuel production is subsidised by governments.”
For example, Miller points out that gasoline is a ‘horribly inefficient’ way to power cars.
“Maize as a resource for ethanol only has an energy payback of 1.3 to 1; in other words you get only 1.3 units of energy back for every unit of energy you put back in.
“If you compare that to the production of gasoline it takes more energy to produce a gallon of gasoline than is contained in the gallon of gasoline.”
“Some valuation of the sustainability benefits that bioenergy/biofuels, done correctly, can provide would help level the playing field and promote greater implementation and use,” adds McMillian.
Even so, McMillian adds “Bioenergy isn’t the end-all magic bullet solution to energy, but simply provides one important set of renewable energy technologies that can help us meet our economic and environmental objectives.”
Initiatives such as effective carbon-pricing – whereby those who emit carbon dioxide are charged for their emissions – would drive governments and investors to move more quickly into a lower carbon economy where biofuels would thrive and more money would be put into driving down the price and speeding up the development of technologies such as ‘artificial energy harvesting forests’ and offshore algae farms currently being researched.
Until then, biofuels will continue to play an important but marginal role in our energy mix.