Digital library

  • The readers chose between transformative bioenergy technologies at more than 250 companies, universities and national laboratories, including 100 organizations that received write-in votes.

    Author(s): Biofuels Digest
  • Rationale: The UK faces major choices about how to move to a secure, low carbon economy over the period to 2050. Should we do more to cut demand, or rely more on increasing and decarbonising the energy supply? How will we produce our electricity? Which technologies will we adopt?Approach: 2050 pathways is a tool to help policymakers, the energy industry and the public understand these choices. For each sector of the economy, four trajectories have been developed, ranging from little or no effort to reduce emissions or save energy (level 1) to extremely ambitious changes that push towards the physical or technical limits of what can be achieved (level 4).Pathways: The 2050 Pathways Calculator – available on the DECC website - allows users to develop their own combination of levels of change to achieve an 80% reduction in greenhouse gas emissions by 2050, while ensuring that energy supply meets demand. This report describes six different illustrative pathways to show the varied routes to 2050, ranging from a pathway that requires significant effort across all sectors to pathways with only a minimal contribution from particular sectors, such as renewables, bioenergy, nuclear or carbon capture and storage, and a pathway with less action on energy efficiency. None of them represents a preferred option.

  • SES was chosen as one of the top 25 Nordic Cleantech Startup Companies.

    Author(s): Seaweed Energy Solutions (SES)
  • After studying algal cultures and seawater samples from the Southern Ocean off Antarctica,  a team from Woods Hole Oceanographic Institution (WHOI) and the J. Craig Venter Institute have found a protein they describe as "the B12 claw."  This article from describes that research.

  • The agar agar obtained from Gracilaria verrucosa growing in commercial quantities in Chilka Lake, Orissa was found to be having an yield of 23% and gel strength of 41 gm/cm . In order to exploit this agarophyte for the same with other agarophytes like Gelidlella acerosa and Gracilaria edulis in three different proportions was studied.

    Author(s): Chennubhotla, V S Krishnamurthy, Najmuddin, M, Nayak, Bidyadhar
  • Between the late 1960s and the early 1980s, several generations of phycologists in Hawaii and the Philippines, associated with M. S. Doty, contributed to developing a new approach, and to advance concepts in marine agronomy. This study reviews the approach and the main concepts contributed. Integrating these contributions with others, a basic conceptual framework for marine agronomy is presented.

    Author(s): B. Santelices
  •  Mariculture accounts for about one-half of total aquaculture production by weight. About one-half of the mariculture production consists of aquatic plants, with the remainder being fish and invertebrates. Nearly all of mariculture is inshore. In contrast, offshore mariculture, which is practised in the open sea with significant exposure to wind and wave action and with equipment and servicing vessels operating in severe sea conditions from time to time, is in its infancy and production is almost exclusively of fish and shellfish. There is an impetus for mariculture to move to the unprotected waters of the open sea. Issues at the local level include competition for space, water quality problems, and a negative public perception of mariculture’s environmental and aesthetic impacts. At the global level, there is concern for food security with expanding population along with the conviction that the potential of the world’s oceans to supplement the food supply is vastly underutilized. Prospecting for suitable locations is a critical part of spatial planning for offshore mariculture’s near-future development. Thus, the objectives of this technical paper are to provide measures of the status and potential for offshore mariculture development from a spatial perspective that are comprehensive of all maritime nations and comparable among them, to identify nations not yet practising mariculture that have a high offshore potential for it, and to stimulate interest in detailed assessments of offshore mariculture potential at national levels.Estimates of offshore mariculture potential are based on key assumptions about its near-future development: offshore mariculture will develop within exclusive economic zones (EEZs), will mainly use culture systems modified from inshore mariculture, and will mainly employ species with already proven culture technologies and established markets. These assumptions set the stage for the identification of analytical criteria. Thus, EEZs were used as spatial frameworks to define the limits of national offshore mariculture development. Potential was defined by the depth and current speed limits on offshore cages and longlines, the cost-effective area for offshore mariculture development, and the favourable conditions for grow-out of representative species: cobia (Rachycentron canadum), Atlantic salmon (Salmo salar) and blue mussel (Mytilus edulis), and integrated multitrophic aquaculture (IMTA) of the last two species. Verification and comparison with existing mariculture showed that, despite the limitations of the data, the results are indicative of offshore mariculture potential within the specified criteria.Offshore mariculture potential is large. At present, 44 percent of maritime nations with 0.3 million kilometres of coastline are not yet practising mariculture. About half of the mariculture nations have outputs of less than 1 tonne/kilometre of coastline. About one-half of inshore mariculture production consists of aquatic plants, but there is little production of plants offshore. Scenarios using 5 and 1 percent of the area meeting all of the criteria for each of the three species showed that development of relatively small offshore areas could substantially increase overall mariculture production. Improvements in culture technologies allowing for greater depths and increased autonomies, as well as the further development of free-floating or propelled offshore installations, would add greatly to the area with potential for offshore mariculture development. Remote sensing for the sustainable development of offshore mariculture is included as Annex 3 to this publication in recognition of the importance of remote sensing as a source of data for spatial analyses to assess potential for offshore mariculture, and also for zoning and site selection as well as for operational remote sensing to aid mariculture management.

    Author(s): James McDaid Kapetsky, José Aguilar-Manjarrez, Jeff Jenness
  • Seaweed is a very versatile product widely used for food in direct human consumption. It is also ingredient for the global food and cosmetics industries and is used as fertilizer and as an animal feed additive. Total annual value of production is estimated at almost US$ 6 billion. Total annual use by the global seaweed industry is about 8 million tonnes of wet seaweed.

    Seaweed can be collected from the wild but is now increasingly cultivated. It falls into three broad groups based on pigmentation; brown, red and green seaweed. Use of seaweed as food has strong roots in Asian countries such as China, Japan and the Republic of Korea, but demand for seaweed as food has now also spread to North America, South America, and Europe. China is by far the largest seaweed producer followed by the Republic of Korea and Japan but seaweeds are today produced in all continents.

    Red and brown seaweeds are also used to produce hydrocolloids; alginate, agar and carrageenan, which are used as thickening and gelling agents. Today, approximately 1 million tonnes of wet seaweed are harvested and extracted to produce about 55 000 tonnes of hydrocolloids, valued at almost US$600 million.

    Author(s): Dennis J. McHugh
  • The identification of similarities in the material requirements for applications of interest and those of living organisms provides opportunities to use renewable natural resources to develop better materials and design better devices. In our work, we harness this strategy to build high-capacity silicon (Si) nanopowder–based lithium (Li)–ion batteries with improved performance characteristics. Si offers more than one order of magnitude higher capacity than graphite, but it exhibits dramatic volume changes during electrochemical alloying and de-alloying with Li, which typically leads to rapid anode degradation. We show that mixing Si nanopowder with alginate, a natural polysaccharide extracted from brown algae, yields a stable battery anode possessing reversible capacity eight times higher than that of the state-of-the-art graphitic anodes.

    Author(s): Igor Kovalenko, Bogdan Zdyrko, Alexandre Magasinski, Benjamin Hertzberg, Zoran Milicev, Ruslan Burtovyy, Igor Luzinov, Gleb Yushin
  • Seagrasses are important habitat-formers and ecosystem engineers that are under threat from bloom-forming seaweeds. These seaweeds have been suggested to outcompete the seagrasses, particularly when facilitated by eutrophication, causing regime shifts where green meadows and clear waters are replaced with unstable sediments, turbid waters, hypoxia, and poor habitat conditions for fishes and invertebrates. Understanding the situations under which seaweeds impact seagrasses on local patch scales can help proactive management and prevent losses at greater scales. Here, we provide a quantitative review of available published manipulative experiments (all conducted at the patch-scale), to test which attributes of seaweeds and seagrasses (e.g., their abundances, sizes, morphology, taxonomy, attachment type, or origin) influence impacts. Weighted and unweighted meta-analyses (Hedges d metric) of 59 experiments showed generally high variability in attribute-impact relationships. Our main significant findings were that (a) abundant seaweeds had stronger negative impacts on seagrasses than sparse seaweeds, (b) unattached and epiphytic seaweeds had stronger impacts than ‘rooted’ seaweeds, and (c) small seagrass species were more susceptible than larger species. Findings (a) and (c) were rather intuitive. It was more surprising that ‘rooted’ seaweeds had comparatively small impacts, particularly given that this category included the infamous invasive Caulerpa species. This result may reflect that seaweed biomass and/or shading and metabolic by-products like anoxia and sulphides could be lower for rooted seaweeds. In conclusion, our results represent simple and robust first-order generalities about seaweed impacts on seagrasses. This review also documented a limited number of primary studies. We therefore identified major knowledge gaps that need to be addressed before general predictive models on seaweed-seagrass interactions can be build, in order to effectively protect seagrass habitats from detrimental competition from seaweeds.

    Author(s): Mads S. Thomsen, Thomas Wernberg, Aschwin H. Engelen, Fernando Tuya,Mat A. Vanderklift, Marianne Holmer, Karen J. McGlathery, Francisco Arenas, Jonne Kotta, Brian R. Silliman