Novel microalgae production method promises cheap fish feed

Spanish company, Algasol Renewables, is setting up a microalgae-to-feed production demo site in the low-lying delta region of Bangladesh, with the support of local and national government agencies. 

Miguel Verhein, Algasol executive director, told us the company expects to be producing feed at the showcase unit in Bangladesh by the end of Q1 2015. The site will, initially, cover 6.5 acres and will produce 25 tons of micro-algae per month. 

The firm’s novel algae cultivation method involves a flexible multi-compartment photobioreactor (BPR) floating on water that can be deployed both on non-arable land in ponds or in the ocean. 

Last month saw Algasol’s long-term partner, US firm, OriginOil, commit to providing the site with the water separation expertise needed to harvest the algae and produce fish pellets.

Aquaculture booming ​

Bangladesh has extensive and highly diversified fisheries resources. Official Department of Fisheries (DOF) statistics estimate total fish production of 2.56 million tons, of which aquaculture accounts for 39%.

Researcher, Ben Belton, in a review of aquaculture and fish consumption in Bangladesh​, says aquaculture and, in particular, more commercially oriented forms of the activity are likely to play a critical role in meeting national fish consumption needs and alleviating poverty in the country. 

He notes that inland pond culture represents the mainstay of aquaculture in Bangladesh, accounting for almost 86% of production.   

Globally, aquaculture is a booming industry. The $100 billion sector is expected to increase by 33% between 2012 and 2022, compared to an increase of only 3% in capture fisheries, according to the UN report, The State of World Fisheries​. ​ ​

But the growth is leading to operational and environmental problems, including the high costs of energy and, in particular, fishmeal, for which alternatives are needed. A lot of research into fish feed alternatives has focused on microalgae sources. 

Floating bag technology ​ 

However, algae production faces two major challenges - cultivating algae quickly and efficiently, and harvesting it at a low cost. 

Verhein says Algasol's patented BPR technology for growing micro-algae in floating bags allows controlled, low-cost production, lowering capital expenditure by 90% when compared to other closed algae growth environments.

“​Bio-reactors are too expensive for massive scale, and open ponds cannot guarantee a contaminant-free environment and have high energy consumption. Temperature control is needed in tube and flat panel methods​, while fermentation methods need sugar as a feedstock, and thus contribute to the food versus fuel ​debate," ​he added. 

The Spanish firm's method, said its executive, also enables optimal light exposure, high biomass concentration, low energy consumption, and efficient system control.

“In terms of biomass generation, our method allows a 100 times greater concentration than open ponds, and two to three times that of tube reactors. The floating bag system​ also uses 70% less water than tube reactors, which are traditionally seen as much more water efficient than open pond methods,” ​said Verhein.

Securing financing for farmers ​

Algasol is set to deliver training to small farmers located in Bangladesh’s delta region in the eventual roll out of the novel growth and pelletizing system there.

"We are actively negotiating deals for micro-financing to get these farmers on board,"​ said Verhein. 

The company's plug and play units range in price from $2,175 for the 10 meter squared Alga4 to $3,375 for the 250 meter squared Alga6 unit.

The Algasol technology has been attracting attention from developing markets, with plans underway to roll out similar feed production initiatives in Mozambique and the Ivory Coast, said Verhein.

It has also registered interest from government agencies in Angola, Mexico, Japan and the Middle East, he added.