Seaweed could fight climate change, claims Crown Estate

A report by The Crown Estate, conducted by researchers at The Scottish Association for Marine Science, has suggested that farming marine algae to be used as biomass fuel would avoid the problems traditionally associated with biofuels such as the use of agricultural land.

The report conceded that more research was needed into how to maximise productivity and the long-tern economic and environmental impact of large-scale seaweed farming.

Professor Mike Cowling, Science and Research Manager at The Crown Estate, said: “Given Scotland’s rugged western coastline and island groups, and relatively clean seas, it is sensible to examine the farming of seaweeds and sustainable harvesting of natural supplies as a source of energy, to heat our homes and fuel our vehicles. Heating and transport make up around three quarters of our energy use so it’s vital that we find new ways of meeting that demand.

“Although more research must be done to establish the practicalities, it seems that seaweed could play an important role in providing a secure and reliable supply of green energy, particularly for coastal and island communities.”

Some of the benefits of marine biomass outlined in the report included:

• it can be anaerobically digested to produce methane which, in turn, can be used to generate electricity for heat or transport (potentially attracting a subsidy under the Renewables Obligation Certificate Scheme)
• it avoids the problem of switching agricultural land from food to fuel production
• unlike terrestrial biomass, it is not be limited by freshwater supplies
• seaweed has high conversion efficiencies and rapid conversion rates
• the residues are suitable for use as nutrient supplements for agriculture
• seaweed farms may also increase local biodiversity, absorbing some of the excess nutrients in run off from agricultural land, which can cause problems such as algal blooms.