Algae grow better on Bonaire
Wageningen University & Research is opening a new algae research station on Bonaire. “We are aiming for some excellent results,” says René Wijffels, professor in bioprocess engineering. “Light incidence and temperature control have been tricky issues in the Netherlands and we hope to make considerable progress in these fields on the tropical island of Bonaire.” The first floating reactors filled with native micro-algae will be taken into use next year.
The algae are already doing what is theoretically expected from them in the Wageningen laboratories: under the influence of light and oxygen, fed with CO2 and some fertiliser, they produce fatty acids and proteins. In the outdoor conditions of the AlgaePARC in Wageningen, however, the single cell organisms have been performing less favourably since 2010 according to various tested reactor formats. “We started with a yield that was five times lower than in the lab, and we are now at a factor of 2.5 of the maximum achievable yield. It is a good result, but there is still considerable progress to be made,” René Wijffels explains.
More sunshine hours and warm seawater
Light incidence makes algae perform better in vertical reactors than in horizontal ponds or tubes. “Vertically, the algae capture more light on the sunny side and experience better cooling on the other, like a row of crops,” Wijffels continues. But still: in winter it gets dark early in the Netherlands, and the algae do not do so well on dreary November days. The same occurs when clouds block the sun on bright days. Bonaire has more sunshine throughout the year and the seawater has a constant temperature. This means, in contrast to the Netherlands, the water will not need to be heated in winter. “In addition, the same sun produces cheap energy for the pumps with which the algae pioneers import clean water and remove fattened algae,” says Wijffels. “The cooling energy is also sustainable thanks to the sun.” This energy is needed because although the algae perform better in warm conditions, they perish at temperatures above 50 degrees Celsius. One of the PhD students will be isolating algae on Bonaire that can resist high temperatures.”The reactors will be built in floating, enclosed basins in lagoons of abandoned salt pans. “This way it doesn’t matter if the lagoon is sometimes flooded by the sea,” adds Wijffels. “Another PhD student will be testing the floating production system.” The European Association of Overseas Countries and Territories (OCTA), the Dutch ministry of Economic Affairs and travel agency TUI are financing the first step of the realisation of the algae research station. “We now have €200,000 for a feasibility study. The NWO Caribbean programme is financing the second stage with €600,000 for two PhD students.”
Economic opportunities for Bonaire
Bonaire is also contributing. The island wants to become less dependent on tourism and increase its economic diversity, for example via fish farming in aquaculture. The fattened algae can serve as a protein and fat resource in fish feed. “Norwegian companies have proven that half of the fishmeal in salmon farms can be replaced. Salmon is gradually becoming vegetarian. On Bonaire, algae meal can be used in shrimp farming or the cultivation of mahi mahi.”The production of fatty acids has been the main subject of interest so far as they can be used to produce biofuels such as kerosene. This also explains the involvement of a major travel agency. “TUI recognises that the economic feasibility of algae kerosene is far from within reach,” explains Wijffels. “Algae kerosene was ten times as expensive as fossil kerosene in 2010 and is still five times more today. We may not achieve a factor of two until 2024.” According to Wijffels TUI is more focused on raising awareness among travellers of the impact of air travel on climate change. For each flight in the Robinson program sold the company deposits an amount in a fund which helps pay for information and promotional activities for AlgaePARC. Many secondary school students go on excursion to Wageningen to write a paper on algae, for example.Other interesting applications for the local economy involve the processing in food to give a salty fish flavour in broth, and algae can also be used in oyster farming or applications such as cosmetics, creams and massage oils. René Wijffels: “We can gain experience in all these possible applications on Bonaire.”