Power Plant: Algae offers up a greener form of fuel
The future of cars is likely to extend beyond that of hydrocarbons, but electric power, hydrogen and biofuels aren’t the only renewable sources of fuel in town.
Algae doesn’t behave like a typical plant in some ways, lacking the distinctive leaves seen in members of the plantae family. However, with its distinctive greenish tinge and the ability to photosynthesise like other plants, algae is still considered a member of this broad family. Now, as petrol and diesel prices rise to new all-time highs and create panic at the pumps, it could become a fuel source for cars of the future too.
Algae in the tank
In the mid-20th century, it would have been unthinkable to imagine how a car might ever be powered in a way that was in any way capable of delivering low emissions. By 2025, this could become a reality, as Formula 1 unveiled plans to produce engines capable of running in precisely this very way. F1 intends to make the switch towards biofuels through the likes of E10, a gas which is 10 per cent ethanol, but added that algae could also play a role in filling up cars of the future too.
Algae is a potential key to sustainable car fuel thanks to being rich in a special oil which, when burnt, still produces CO2 but only that which was originally inhaled by the algae as it grew, avoiding adding any more CO2 to our atmosphere. This compares with most existing fuels like petrol or diesel which release large quantities of carbon sequestered millions of years ago from the bodies of ancient organisms. As an additional benefit, when algal oils are consumed, no nitrous dioxide or sulfur dioxide are released into the air, as happens when hydrocarbons are burnt. When released, these dioxides do immense damage, causing acid rain and breathing difficulties. By switching to algal oils, our skies become less ominous and we can potentially start to breathe easier again.
One of the factors which could make algal fuel such a compelling source of fuel of the future is algae’s ability to grow rapidly under certain conditions. As anyone who knows a bit about growing plants will attest to, fertilisers are an algal bloom’s best friends; many ponds and lakes experience rapid transformations in a few short weeks, when fertilisers leak into them through soil spillage.
Wastewater is one way of possibly helping ensure we have large quantities of algae at our disposal in the future, but algae is still a form of plant, so the nutrients we feed it must still be treated in a specific way to avoid killing the algae entirely. For example, industrial fertilisers often contain metallic contaminants, but it has been suggested algal strains resistant to this contamination could be used to overcome the issue.
Algae has great potential as a form of biofuel as it produces oil with greater yields than rapeseed, palms, or soybeans. If left in the ideal conditions, algae can be harvested for use in as little as one to 10 days. In a world where we need a readily available source of biofuel, algae could just fill the gap left by hydrocarbons, if other sources of sustainable car fuel remain less economical until later in the next century.