As the search for alternative energy sources grows more urgent, we could soon turn to the sea to address these needs. Cue seaweed.
But, what exactly can the sea offer? Well, seaweed is something that is of huge abundance, and it grows remarkably quickly with little to no effort.
This makes it have great potential to be a sustainable source of algae-derived renewable energy, also known as third-generation biofuel.
bioethanol as a substitute for fuel.
I’m sure most of us already know that crude oil is the source of various hydrocarbons such as naphtha and petrol, but did you know that biofuel is derived from various plant matter?
Alternative sources of fuel such as bioethanol, biodiesel and biogas are created from nature’s finest, and by far the most widely produced biofuel is bioethanol, which is created by fermenting plant matter with the help of yeast. Bioethanol is considered the ideal replacement for traditional fuel due to its chemical similarities to ethanol.
First-generation biofuels denote primary food crops like corn or sugarcane which are converted into ethanol. Second-generation biofuels improve on this by only using the inedible parts of food crops, such as rice husks, thereby increasing the versatility of these crops. However, both first and second-generation biofuels face challenges because of the cost of their production and the need to destroy habitats just to fuel the… erm biofuel.
Hence, seaweed, or algae-based plants in general, is now considered the most viable and scalable source of biofuel. This is largely due to its easy cultivation and harvest, with some kelp species able to grow 50cm over the course of a single day! (Wish I had that same amount of growth)
Other species, like spirulina, can still grow a commendable 30cm daily. With such incredible growth rates, they can be harvested after short periods of time, making them attractive sources of renewable biofuel.
Gonna get a little sciency here. Being photosynthetic, they can store chemical energy in their cells which we can harness for power generation. Seaweed is also superior to land-based plants in terms of biochemical composition as they have a high concentration of carbohydrates, yet low levels of insoluble plant cellulose. This makes it easy to extract the sugars needed for fermentation. Other families of seaweed, like Enteromorpha, are also high in fat content, making them useful for biodiesel production through lipid esterification.
Basically, in layman’s terms seaweed = good.
tons of space in the sea.
70% of the Earth’s surface is dominated by vast, vast oceans. Although most of it is unsuitable for farming (you wouldn’t want to farm in the middle of the Pacific right), seaweed is surprisingly adaptable, and its hardiness means it can grow in both warmer and colder climates.
Virtually any country hugging a coastline can farm and harvest seaweed, making it easily accessible to the masses. Best of all, nothing needs to be cleared, unlike traditional land-based cultivation.
there is a catch.
Yes, biofuel production is not fully carbon neutral. But, the carbon footprint is a tiny amount compared to fossil fuels.
The biggest issue with this seemingly perfect solution is its cost. While highly efficient energy-wise, the cost to produce biofuels from seaweed is much higher compared to first and second-generation methods. This is partly due to poor current harvesting techniques.
As seaweed farming technology catches up, we’re sure to see more efficient practices combined with genetically engineered strains of seaweed that will improve its feasibility and appeal as an alternative energy source.
Grow tall my grassy friends!
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