Although fossil fuels have been an essential energy source for many centuries, they come with many disadvantages that do more harm than good in the long run. Algae biofuels may be the future of alternative, renewable energy resources. Still relatively new to the research and energy industry, algae biofuels have the potential to produce a lot of energy while being sustainable and beneficial for the environment. Algae are microorganisms that grow in aquatic environments and undergo photosynthesis to create biomass. A few companies have attempted to test the waters of algae biofuel production and the market, but currently none are able to maximise productivity and cost efficiency in the production of algae biofuels, leaving many doubtful of its potential. However, the extent of its potential and use have not been discovered yet, so research and development (R&D) of algae biofuels is still ongoing, and it is only just the beginning. Companies such as ExxonMobil are currently undertaking research and trying to engineer a strain of algae that can be used to mass produce algae biofuels at an industrial scale. In the process of R&D of algae biofuels, problems and hurdles will arise, but hopefully in the near future, they will be overcome and solved.

Renewable energy source

Algae was initially considered as a potential source of renewable energy because as oil prices rose due to non-renewable resources becoming scarcer, there was a growing, global interest in alternative, renewable energy resources that can create higher energy content per unit volume of biomass. Algae fits the picture, as algae feedstock can harvest more energy compared to other crop feedstocks, such as corn. Algae can produce approximately 20-30 times more oil than corn or other crops. Not only can oil from algae be continuously harvested, algae use light and consume carbon dioxide (CO2) waste to produce more algae, minimising CO2 in the air and surrounding environment. Besides harvesting oil from algae, the algae can also produce other products such as hydrogen gas and methane biogas under certain conditions.

The production of algae biofuels is sustainable as it provides endless amounts of resources as algae multiples over time at a rapid rate, potentially doubling its initial mass within a time span of a day. Microalgae mass culture can be cultivated on land that is not suitable for other crops such as nonpotable saline water and wastewater. By culturing the microalgae in wastewaters, it can help remediate the wastewaters by removing nitrates and phosphates from the water and capturing sulfates and CO2.

Environmental benefits

Algae biofuels are generally safe and beneficial for the environment. When vehicles and engines are running on biofuels, CO2 emissions can be reduced close to zero. Although algae biofuels emit CO2 in the air, algae mitigate those emissions by absorbing them back, therefore, making the net emissions close to zero.

Therefore, the air quality can be improved when using biofuels. In addition, algae biofuels are less combustible compared to fossil fuels and when released into the environment through accidentally spilling, less damage is dealt to the environment compared to a petroleum spill.

Challenges

With many advantages in sustainability when producing and using algae biofuels, there are also disadvantages and challenges associated with algae biofuels. With the current technologies, processing methods, energy balance, and land occupied by algae farms, the commercialisation of algae biofuels is currently not viable on an industrial scale. With current technology, 39 billion litres of algae biofuels are produced a year, which is 5% of US transportation fuel needs alone. For the past decade, prices of fossil fuels have remained low. The cost of a barrel of algae biofuel grown at a pond scale is estimated to be $240 (€202) whereas the cost of a barrel of competing crude oil is $40-$50 (€33-€42). With a cheaper price tag for fossil fuels, there is low demand for algae biofuels at this time. The cost of production, transportation, and resources used to harvest algae biofuels are also high due to the current processes and reactor designs used to cultivate algae. To lower the prices of algae biofuels and make production feasible, researchers and engineers must come up with new, innovative methods and technology to combat those issues and be able to produce algae on an industrial scale.

The current algae mass culture farm systems are not efficient and viable for mass production. The open pond system is the oldest and simplest system used to cultivate microalgae. Although this system does not cost a lot to build, it expels a lot of resources and is wasteful. A lot of water is lost due to evaporation and growing microalgae in an open system does not uptake CO2 efficiently.

By continuing research in finding new microalgae strains or engineering genetically altered microalgae strains, a microalga with higher percent yield of oil per unit biomass can be attained. When technological advances and efficiency gains are made, algae biofuel production can have higher biomass yields per acre and higher percent yield of oil content per unit biomass. This would help to lower the cost of production and overall cost of the product sold as fuel. The future of algae biofuels may seem unclear right now, but by putting more funds and time into research and development in all the different aspects of creating sustainable and highly optimal algae biofuels, industry-scale commercialisation of algae biofuels will be possible.

This a truncated article originally publishes by Biofuels International Magazine. The whole article cane be viewed at Biofuels News