Seaweed may become a marine industry

Dr Craig Rose, guest lecturer at Newcastle University, told MJ that seaweeds have huge potential far beyond the harvestable wild stocks available in the UK and Europe.

“Consequently, cultivation of seaweeds offshore is expected to be a very significant marine industry that may need to produce hundreds of thousands of tons a year”, he said.

Application areas include the biofuel sector, as the plants can be harvested for biogas, bioethanol, biobutanol and biodiesel. However, the life science and biomedical sector is also interested as seaweeds extracts such as fucoidins, laminarins, polyphenols may be useful in cancer treatments as well as other health related applications. Last but not least, there is a small tradition of using seaweed as a food crop.

But although companies such as Exxon are investing $600m in synthetic genomics for the development of algal biofuels, these are as yet 15 to 20 years from a reasonable scale of commercialisation, according to Dr Rose, whereas aspects of the life science and food industries are already in place, and with immense potential to grow.

However, energy and biofuel development remains the main focus of investment. As seaweeds do not require freshwater and do not compete for land with food crops or natural habitat they are far more sustainable than other sources of biomass such as land based plants. There is increasing regulatory and market pressures on biofuel sources to be more sustainable.

The bulk of the investment so far has come from governments, particularly in the USA, although the private sector has started investing in biofuel technologies and the development of commercial facilities. Some small scale production is already underway. For example, in 2010 Solyzmes delivered some 80,000 litres of algal derived biodiesel and jet fuel.

However, common to all the industry sectors discussed above, the all too often overlooked difficulty is the emerging bottleneck of the availability and sustainability of the seaweed harvest. Most is either harvested from the wild and carefully regulated, or cultivated on ropes in offshore waters.

In the UK there is only one commercial operation in the UK harvesting wild seaweed and at a relatively low volume, according to Dr Rose. As yet there is no significant commercial scale cultivation of seaweed, but as with many new technologies, costs will eventually come down and many will be searching for that tipping point where the outlay dips and the market starts to rise.