EDF Trading enters international biomass market

EDF Trading (EDFT), the subsidiary of utility Electricité de France (EDF) responsible for wholesale market activity, has acquired biomass company Renewable Fuel Supply Limited (RFSL). EDFT is one of the largest pan-European, multi commodity wholesale traders of electricity, oil, gas and coal.

RFSL provides a biomass procurement service and logistical and technical support to coal-fired power generation companies that wish to co-fire biomass with coal. It has supplied over 400,000 tonnes of biomass since 2004, according to EDF.

Staff from RFSL who have moved to EDF Trading’s London office include Hank Jones, who will lead the biomass business. Jones was a co-founder and director at RFSL and has a wide range of experience in the energy sector, including posts at American Electric Power in London and Duke Energy Resource Corporation in Houston. Other team members include Nick Tsirigotis, Chris Matthews, and Scott Dooley.

EDF Trading has significant electricity, emissions, coal and freight trading businesses in the physical and financial markets so biomass is complementary to our existing activities. RFSL’s business also has synergies with the EDF Group who are committed to sustainable development and the production of electricity from renewable energy sources. - John Rittenhouse, managing director of EDF Trading.

RFSL researches and adopts many sources of biomass and new uses for these fuels. To date, the following are its most commonly traded biofuels for co-firing:

• wood pellets (from the UK, Scandinavia, North America...)
  
• shea meal and pellets (Mali, Cameroon, Congo, Côte d'Ivoire, Ghana, Guinea, Nigeria, Senegal, Burkina Faso, Uganda...)
• energy crops (anywhere)
  
• olive cake and pellets (Southern Europe)
  
• palm kernel expeller (Malaysia, Indonesia, South East Asia, Africa)
  
• palm kernel shells (South East Asia)
• grape seed expeller (Europe, any wine-growing region)
  
• copra meal and pellets (South East Asia, Caribbean)
  
• liquid biofuels (crude palm oil, rapeseed oil...)

As can be seen, many of these biomass sources are agricultural residues for which farmers now receive a price, whereas before they would have had to pay to dispose of the residues. Especially for small farmers in the South, this new international biomass market opens interesting perspectives. Many more field and processing based residues than the ones listed here, could become viable and internationally tradeable biomass resources (a short overview of residues in the developing world). In theory, millions of farmers are now potential energy producers, whereas during the fossil fuel era, only a few countries, companies and sites were suppliers of energy. Bioenergy thus implies a kind of 'democratisation' of energy supplies.

A look at the supply chain
But in order for a coal plant to co-fire renewable biomass, a relatively complex supply chain [*.pdf] must be followed that depends on diffent transport modes and options (schematic, click to enlarge), the type of biomass and its origin, the continuously changing price of coal and the type of coal plant. Unlike fossil fuels, biomass is a natural product: its availability follows cyclical patterns and its chemical composition as well as its mechanical and combustion properties differ from one source to another:
bioenergy :: biofuels :: energy :: sustainability :: co-firing :: coal :: residues :: waste :: biomass :: supply chain ::

The first, critical step is careful selection of biomass to provide the user with a low cost biomass offering low plant risk and minimal capital investment. Biomass should avoid degradation of boiler steam raising capacity, and therefore the grindabilty and CV of the biomass are important parameters. These parameters show some seasonal variabilty.

Development of a just-in-time biofuel pipeline is then applied to an identified biomass source. This is not only the lowest working capital solution but also offers unparalleled flexibility to change fuel characteristics in response to changes in the power and coal markets.

The supplier then has to modify biomass at the procurement stage on behalf of the customer in order to obtain desirable mechanical and chemical properties. For example, pelletising of biomass (like olive residues) might be needed in order to reduce dust and odour whilst increasing furnace throughput. Biomass material must also be free from trace element contamination and aflatoxins.

Biomass offers many mechanical handling challenges, not just during the unloading of trucks but at every stage of the fuel handling route to the coal bunker. Careful selection of biomass products according to size distribution and minimum moisture content must ensure that a heathly working environment is maintained.

Commercially successful co-firing requires the biomass supplier and the power station to work closely together to develop a storage and logistics solution that offers the following (mutually competing) characteristics:

• Low capital cost
• Low working capital
• Fast to implement
• High reliability of fuel delivery

Onsite selection of storage solutions as part of the development of an optimum logistics chain is crucial.

RFSL works with accredited dust explosion research centers and major boiler manufacturers to establish comparative explosive characteristics for biomasses. Biomass tends to be highly volatile compared to traditional UK coals and milling plant often operates at temperatures close to the onset of thermal decomposition of biomass. RFSL supports the selection and testing of biomass in recognised industrial explosion testing research laboratories.

The high alkalinity of biomass ash together with the presence of fluxing agents can lead to increased fouling and slagging. This can be avoided with careful selection of biomass and coal, coupled with adoption of a biomass dosing system which has been designed for close control of biomass dose rates, thereby avoiding overdosing and the ensuing risk of fouling or slagging.

After the biomass has been co-fired, the ash must be utilised or disposed of. Biomass ash tends to be high in alkaline oxides compared to coal ash, and these oxides can increase the ash pH. This can result in low pH runoff from hydraulic disposal systems. Highly fertilised biomass, such as wastes from foodstuff crops, can also present highly soluble phosphate compounds in ash. Hence, it is very important that co-firing stations select biomass carefully.

In short, biomass supply chains are quite complex and dependent on continuously changing parameters. This complexity partly stems from the fact that the carbon neutral resource interacts with another fuel (coal), which alters parameters both at the beginning and the end of the chain.

Schematic: taken from IEA, "Sustainable International Bioenergy Trade: securing an international supply and demand", introductory leaflet [*.pdf].

References:
Energy Risk: EDF Trading moves into biomass market - July 2, 2007.

Renewable Fuel Supply Limited: overview of technologies for biomass supply chain management.

Energidata AS, Transportøkonomisk institutt (TØI), KEMA Consulting, "Bioenergy logistics chain cost structure and development potential" [*.pdf], IEA Bioenergy Task 40, November 2005