The mobile pellet plant

Bringing bulky biomass to market in an efficient way is one of the biggest logistical problems for the development of the green fuel sector. Plants growing on a plot of land act like a very low-cost solar energy collector. As they grow, crops convert sunlight and CO2 into biomass, which stores the solar energy. But crops like tall grasses or residues like hay and sawdust are rather bulky: compared to oil or coal, they take up much more space to pack a similar amount of energy.

For this reason, biomass is first converted into a fuel with a higher energy density before it is transported to market. Several concepts exist aimed at overcoming this problem: biomass can either be collected and transformed into an energy dense bio-oil (pyrolysis oil) in decentralised plants, after which the oil is transported to more centrally located "biorefineries" where it is turned into marketable products like green gasoline and diesel fuels, or building blocks for green chemistry. Another, more simple concept consists of densifying bulky biomass into pellets or fuel briquettes. Such pellets can then be used in power plants (in combination with coal or as such) as well as in household pellet stoves and small combined heat-and-power systems as an alternative to heating oil.

Over the past years, the biomass pellet market in the EU and to a lesser extent in the US has skyrocketed because the fuel is considerably less costly than heating oil. Whereas the NYMEX heating oil price this month averaged around US$1.86 per gallon (US$0.49/€0.36 per liter), a ton of pellets stood at around US$150 per ton. With a heating value equivalent to around 17MJ/kg versus 35MJ/liter for heating oil, the cost of a gallon of heating oil equivalent energy contained in pellets is around US$1.25 (US$0.33/€0.24 per liter), a considerable difference. Heating oil prices topped US$ 2.25/gallon last year.

The favorable economics have seduced several entrepreneurs to step into the opportunity. Large scale pellet mills are under construction in the US (earlier post), where producers eye exports to the EU, in South Africa (earlier post) and in the Republic of Congo, whereas the already well established European industry is booming (overview of the market for solid biofuels in the EU).

However, smaller and creative players are entering the arena too. An entrepreneurial family in Northeastern Pennsylvania , for example, has begun to experiment with an concept it thinks will make a difference: a mobile pelletiser. The machine can be brought to the field and transform grasses or agricultural residues into market-ready solid biofuels. The Reggie family grows switchgrass as the feedstock on its own land. The Reggies feel the concept will preserve farmland, create wildlife habitat and lessen America's dependence on foreign oil.

Every day, Leonard Reggie and his two sons, Bryan and Adam, work on fabricating, welding and building the machine that will transform common switchgrass into an affordable and abundant heat source. They organised their efforts in a company called BHS Energy LLC. Although the design and construction of the mobile pellet mill are complex, the concept is simple: bales of switchgrass are placed in one end, ground up and compressed into half-inch pellets that resemble rabbit feed:
bioenergy :: biofuels :: energy :: sustainability :: heating oil ::switchgrass :: pelletiser :: pellets :: biomass ::

When burned, the pellets don’t release carbon into the atmosphere and 5 tons can heat an average home for a year, Bryan said. Simply put, the Reggies believe they are onto something big, and all three have left their jobs to work full time on the endeavor. “This is totally sustainable,” Leonard said. “It can be done indefinitely into the future without harming the environment, and it’s probably the least expensive option to replace heating oil.”

Leonard came up with the idea to pelletize biomass (renewable, organic matter) and use it for heat several years ago. He was in business making cabinets when things began to slow down and he looked for something else. Shortly after Leonard conceived the plan, energy costs plummeted and he abandoned the idea. In 2005, oil prices skyrocketed and, with the encouragement of his two sons, Leonard rekindled the biomass idea.

Adam, who graduated from Penn State Harrisburg with a degree in mechanical engineering technology, left his job with Specialty Defense in Dunmore to join the family business. Bryan, an electrical engineering graduate from Penn State Erie, left his career with Lockheed Martin last summer and the trio formed BHS Energy.

Today, Leonard and his two sons spend their days on the farm, planting switchgrass or building the pellet mill in their spacious workshop. “I actually enjoy getting up and going to work for a change,” Adam said. “I always wanted to do engineering and work for myself.”

They hope to have the machine ready to go this summer, and local farmers have already expressed interest, they said. “There are a lot of farms here that haven’t been used in years, and we’re trying to lease their land to grow switchgrass,” Bryan said. “It’s a good way for people who own land to get money to pay their taxes.”

Because the pelletizer can be hauled to the farm, farmers can raise their own switchgrass and sell the pellets. Leonard said a farmer can make an annual profit of $500 per acre, more than any other crop. The pelletizer can be operated with a 65-horsepower tractor in the field, he said, so farmers don’t have to haul the bales into a barn.

Another benefit, he said, is the switchgrass, which grows 5 to 6 feet high, provides for excellent wildlife habitat and only needs to be planted once. “This is a native grass that grew in the prairies,” Leonard said. “It can produce a yield of 3 to 5 tons per acre every year, and it requires minimal fertilizer and no chemicals to control weeds.”

The Reggies don’t expect everyone to take their word on the benefits of switchgrass pellets, so they are going to practice what they preach. Adam said their barn is filled with switchgrass bales that will be used to heat their house, shop and barn this winter. They will also plant their entire 18-acre farm in switchgrass.

The estimated cost of the pelletizer will be around $60,000, and the Reggies are exploring the possibility of renting machines. They hope to have units ready to sell this July, and intend to produce two to four per month. “Our goal is to give people the ability to produce their own energy,” Bryan said. “You can’t drill for your own oil, but you can grow switchgrass.”

More information:
Times Leader: "Family sees hot promise in pellets" - April 26, 2007.