Heating is the largest energy expense in most homes, accounting for 35% to 50% of annual energy bills. Now, a new and cleaner solution is making an appearance on the market.
The pellets are set to save homeowners a fortune in home heating costs.
Some regional agronomists have devised a way to press grass into pellets and they hope to jump start what could be the next biofuel home heating market.
Pocono Northeast Resource Conservation & Development Council in Dalton, using a US Department of Agriculture grant, is touring its 10-county coverage area to demonstrate its pelletizer machine which has been in development for eight years now.
Will Brandau, now a council board member and grass farmer from Wapwallopen, has been working on the pellet-making process since 2006 and over the last 10 years, he has managed to produce 800 to 1,000 pounds (350 to 450 kg) per hour.
Environmental benefits and lower costs
The council estimates that landowners who grow their own grass can heat their homes for around $500 each winter and experts say that grass pellets burn in most stoves or fireplaces, although special pellet stoves burn cleaner and more efficiently.
They also generate more ash than wood pellets. However, biofuel experts say grass is highly beneficial for those who live in regions with large fields. "Biomass has some advantages in rural areas in terms of providing new markets for agriculture systems," said Tom Richard, Ph.D., director of Penn State's agricultural and bio-engineering department. He says that the grasses are particularly attractive in areas that have water quality concerns because they can soak up nutrients and even prevent erosion.
Making the grass pellets
Just about any growing thing can be pressed into pellets but the trick is getting the moisture content just right which, according to Brandau, is around 15%. This is determined by using a moisture sensor which costs a mere $30 at a local hardware store.
The pellets are made through a simple process first by grinding dried grass into small pieces using a hammer mill, then feeding it into the pelletizer. Inside the pelletizer, heavy metal wheels revolve on a flat, round die punched full of holes. Friction from the rollers on the grass creates heat, reaching boiling temperatures. The gear-like rollers then force grass down through the die holes.The heat breaks down a gluey substance in the plants called lignin which creates a plastic-like coating around the pellets as it cools. A spinning blade underneath cuts off the emerging strands, like noodles through a pasta press, producing short pellets that dump into a waiting bucket.
People have made grass pellets for years, said Dr. Richard, but it's difficult because grass has much less lignin than trees. Grass also holds great promise in the effort to find an environment-friendly fuel source.
When it's alive, grass absorbs carbon dioxide, the same greenhouse gas released when it burns creating a cycle. Warm-season grass dies in winter and decomposes, so harvesting it eliminates that carbon from going back into the ground, Dr. Richard said.
It costs between around $1,100 and $7,500 for a small pelletizer machine setup.
Because a farmer might use it only once or twice a year, George E. Kauffman III, executive director of the Pocono Northeast Resource Conservation & Development Council in Dalton, says it makes more sense for farmers to share the cost and savings.
Biomass pellets market growth
The use of biomass pellets for heating and as a power source has increased significantly recently with many households and industrial facilities using pellet stoves or boilers over old-style wood-fired equipment. According to Research and Markets’ report, "Global Biomass Pellets Market 2015-2019", the global market is set to grow at a CAGR of 11% over the period 2014-2019.
These pellets are generally derived from various sources including the timber industry, sawdust, sugarcane crop, woody plants, and switch grass or miscanthus.
According to the report, power generation using biomass pellets is seeing an increased use especially since biomass is an ideal substitute for conventional fossil fuels for heating and power generation purposes. This is thanks to a growing number of technical options available as well as biomass gaining importance as a renewable energy source.
The report highlights that the costs of setting up biomass facilities can be quite high in comparison to that of other renewable sources and fossil fuels. We are of the opinion that for biomass to meet stringent sustainability targets, innovation and government support will be key. [Innovation will see biomass develop.]
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