Fossil fuels are running out, which means we need to find new sources of energy! But what has this got to do with algae? Algae use the sun’s energy for photosynthesis and growth. We can exploit this process, and use algae to produce electricity. But this is not all: algae can also make hydrocarbons - similar molecules to those found in fossil fuels - which can be used directly as a source of biofuel.
Why is this important?
We need to find new sources of energy, because in the not too distant future we will have used up all the supplies of fuels such as oil and gas. In addition, fossil fuels release a lot of pollutants into the atmosphere when they are burned, whereas energy from other sources can be much 'cleaner'.
Algae can be used to produce electricity. They can split water into hydrogen and oxygen. If the hydrogen can be captured, it can be used in 'hydrogen fuel cells' to generate electricity - and this type of electricity production doesn't release greenhouse gases. But this is not all: algae can also produce hydrocarbons - similar molecules to those found in fossil fuels - which can be used directly as a source of biofuel.
Algae could be a good source of fuel because:
They grow very quickly, and can always be replenished (they are a sustainable source).
Unlike using wood from trees, algae do not require destruction of countryside, as large amounts of algae could be grown and cultured in large tanks of water on wasteland and industrial sites.
Who studies algae?
Many different types of scientist are involved in researching the best way to use algae as a source of energy. Physiologists study how algae are able to combine molecules to create new products such as oils or starches. Molecular biologists study the genetics of different types of algae, and can help work out which species will be most useful. Engineers and chemical engineers use the information that the biologists give them, and work out how to get energy from algae on a large scale that can be used by humans.
What do they need to find out?
There is a lot of research still to be done before we can use algae as a source of energy. At the moment, algae are quite expensive to grow, are difficult to grow on a large scale, and processing them can use up a lot of energy, which is no good if we are hoping algae are going to provide energy for us!
What else can algae do?
Not only might algae provide us with a clean source of energy in future, they can also help us clean up current industrial processes. When algae grow, they photosynthesise rapidly, taking in CO2. Therefore if algae are put in the chimneys of power plants burning fossil fuels, they can remove some of the CO2 before it is released into the atmosphere. Algae can remove other substances too. In waste water from industrial plants, there are often high levels of nitrates and phosphates, which can be damaging to the environment if they get into river systems in high concentrations. Algae can help remove some of these compounds, because they use them for growth. In addition, using algae can be a cheaper way of getting rid of CO2 or nitrates than using man-made products.
Algae have an important role to play in the world's carbon cycle. Algae are the largest group of organisms that photosynthesise, and they take out more CO2 from the atmosphere than any of the plant species. What would happen to the world if a disease came and wiped out all the algae?