Biofuels from the sea

Jul 04, 2011
Kelp (Laminaria digitata) forests off the coast of Wales have been shown to provide a viable biofuel especially if harvested in summer. Credit: Dr. Jessica Adams

Seaweed may prove a viable future biofuel – especially if harvested in summer.

The use of kelp (Laminaria digitata) could provide an important alternative to terrestrial grown biofuels; however the suitability of its chemical composition varies on a seasonal basis. Harvesting the kelp in July when carbohydrate levels are at their highest would ensure optimal sugar release for production.

"The storage carbohydrate and soluble sugars get converted into ethanol in the fermentation process, so we need as much as possible," explains Dr. Jessica Adams, a lead researcher at Aberystwyth University. "Metals can inhibit the yeast too so we also want these to be as low as possible."

Collecting monthly samples of kelp from the Welsh coast researchers used chemical analysis to assess the seasonal variability. Their results, which will be presented at the Society for Experimental Biology Annual Conference in Glasgow on the 4th of July, showed that the best month for biofuel harvest was in July when the kelp contained the highest proportions of carbohydrate and the lowest metal content.

Kelp can be converted to biofuels in different ways including fermentation or anaerobic digestion producing ethanol and methane or pyrolysis, (a method of heating the fuel without oxygen) which produces bio-oil. The chemical composition of the seaweed is important to both of these processes.

Research into biofuels has focused on terrestrial plants; however these have the serious drawback of the conflict between using land to grow food or fuel. Marine ecosystems are an untapped resource that account for over 50% of global biomass and seaweeds themselves are capable of producing more biomass per square metre than fast growing terrestrial plants such as sugar cane.

"Seaweed biofuel could be very important in future energy production," says Dr. Adams. "What biofuels provide that other renewables such as wind power cannot is a storable energy source that we can use when the wind drops."
Future work will improve the viability of the process by identifying and extracting high value substances, such as pigments and phenols, before the rest of the seaweed is used to produce biofuel.

Explore further: Vermicompost leachate improves tomato seedling growth

Provided by Society for Experimental Biology

not rated yet
add to favorites email to friend print save as pdf

Related Stories

How much mileage do you get from sawdust?

Jun 27, 2011

As vacationers gas up to hit the road this summer, they could find themselves wondering about alternative fuels and their potential to ease the strain on pocketbooks and the environment.

Microbes fuel energy debate

Jan 22, 2009

Microbes may well be the answer to our global energy crisis. By fermenting biomass to produce biofuels, they offer a possible climate-friendly solution to the anticipated shortfall in fossil fuel supply. A review by Professor ...

Recommended for you

Vermicompost leachate improves tomato seedling growth

Nov 21, 2014

Worldwide, drought conditions, extreme temperatures, and high soil saline content all have negative effects on tomato crops. These natural processes reduce soil nutrient content and lifespan, result in reduced plant growth ...

Plant immunity comes at a price

Nov 21, 2014

Plants are under permanent attack by a multitude of pathogens. To win the battle against fungi, bacteria, viruses and other pathogens, they have developed a complex and effective immune system. And just as ...

Evolution: The genetic connivances of digits and genitals

Nov 20, 2014

During the development of mammals, the growth and organization of digits are orchestrated by Hox genes, which are activated very early in precise regions of the embryo. These "architect genes" are themselves regulated by ...

Surrogate sushi: Japan biotech for bluefin tuna

Nov 20, 2014

Of all the overfished fish in the seas, luscious, fatty bluefin tuna are among the most threatened. Marine scientist Goro Yamazaki, who is known in this seaside community as "Young Mr. Fish," is working to ...

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

Mattsci
not rated yet Jul 06, 2011
A potentially very useful discovery, however I have a few questions:
I know that the giant kelp species grow particularly swiftly, but would the individual plants be able to compensate for this harvesting? how much kelp would be needed to create a litre of fuel? Would it be economical given the amount of fuel needed, and the expense that could potentially be involved in the creation of "kelp-farms"?
Such questions need to be answered for a holistic article.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.