When Yousef Haseli takes a walk in the forest, he sees the future of fuel.
The Central Michigan University faculty member in the
School of Engineering and Technology is researching ways to improve upon or discover new methods to produce clean, efficient and renewable energy. For that, he's looking to the trees.
Cleaner than coal
Healthy trees, he explained, naturally remove carbon dioxide from the air and return oxygen. Burning wood to create energy releases that carbon dioxide, which other trees absorb.
"We are closing the cycle of carbon dioxide," he said.
Fossil fuels such as coal, on the other hand, are not renewable, and when coal is burned it emits sulfur and dangerous metals such as mercury, lead and arsenic.
But wood directly from trees is an inefficient fuel source compared with coal. For example, a kilogram of coal creates about 29 megajouls (units of energy), but a kilogram of wood creates about 17.
The drier the better
The main drawback of wood is its moisture content. Haseli is researching ways to remove that moisture. A process called torrefication that "toasts" wood to remove its moisture can push its energy yield to more than 24 megajouls — almost in coal territory.
Haseli is developing new processes for torrefication, for which he said he has patents pending.
Because toasting makes the wood similar to coal, torrefied wood can be used by itself or mixed with coal in the furnace of existing coal-fired power plants without major modification, reducing emissions and cost.
It also cuts transportation costs to businesses and homes that use wood for energy. The United States is the top exporter of wood pellets to Europe, which uses them for fuel. Torrefied wood pellets produce more energy per cubic foot than regular wood, and because they have higher energy density, more pellets can be loaded onto one ship.
But that's not all
Wood also can be transformed into syngas, or synthetic gas, through a process called gasification, which can be used in steam power plants, gas turbine power plants and fuel cells. It also can be turned into biofuels, such as ethanol and biodiesel through a process called pyrolysis.
Haseli and the six seniors are designing a lab-scale gasifier that he hopes will be constructed by the end of this semester.