Minnesota Stories:

Christine Lee: Woody Biomass for Minnesota's Future

Regular contributor Christine Lee discusses an alternative energy source that's gotten less attention than others.

As we enter a new decade, we will be presented with many opportunities for change. Particularly when it comes to energy and the environment, it seems that we have finally recognized our crisis, acknowledged our follies, and opened our minds to change. Although coal and natural gas continue to be widely used to cover our gas and electric needs, it’s time we admit that these resources will ultimately dissipate. Naturally, many Minnesotans are weary of nuclear energy (especially if a much-discussed nuclear waste disposal site is installed in Minnesota), and solar and wind power, although generally reliable energy sources, can pose some challenges, like location, weather and cost. Therefore, it’s time Minnesota invests more rigorously in the dependable, clean and most importantly, renewable, energy that woody biomass can provide.

District Energy

Many St. Paul residents may be surprised to learn that their electricity already comes from woody biomass. District Energy, located in downtown St. Paul on the banks of the Mississippi River, is the largest wood-burning plant in the United States and heats nearly 200 office buildings and 300 single-family homes in Minnesota’s capital city. Although it keeps a relatively low profile, District Energy is widely considered to be among the most successful plants in the United States in terms of renewable energy and energy conservation.

Hybrid poplars used for biomass

In recent years, woody biomass has come to light as an integral strategy for addressing both energy and environmental concerns across the United States. Broadly defined, woody biomass includes trees and woody plants, including limbs, needles and leaves. Woody biomass can be harvested and burned to provide electricity or heat, similar to the way coal is burned. The benefits and advantages of woody biomass over other traditional energy sources are many: ?

•    Since trees soak up carbon while they are growing, burning a tree for energy production is ultimately carbon-neutral; coal can’t argue with that.
•    Woody biomass is always available. Trees can be stored indefinitely and grow incredibly fast. In Minnesota, it is becoming increasingly popular to use Hybrid Poplars, an amazingly fast-growing tree that provides lots of woody biomass from a small amount of land.
•    Since Hybrid Poplars or other trees provide more energy per acre, this frees up land for conservation or other crops; corn-based ethanol consumes more land to provide less energy.
•    Selectively harvesting trees for woody biomass utilization can help minimize the spread of the increasingly common and devastating wildfires across the United Sates, as well as help minimize the spread of invasive species and destructive tree diseases.
•    When woody biomass is burned in an appropriate facility, it results in significantly lower air pollution than if these trees had burned in a harmful wildfire.
•    Most importantly, woody biomass is produced here; supporting local economies.

Lowering energy costs and reducing our reliance on turbulent, oil-producing countries.
Certainly, woody biomass is not perfect – no one alternative energy source is. There are many critics of woody biomass out there who would argue, in fact, that woody biomass is destroying our forests or produces air pollution.

However, to this I would first respond that a woody biomass plant that is in a state with responsible and enforceable policies (like Minnesota), they would be selectively harvesting trees and thereby minimizing wildfire risk; and never harvesting from old-growth forests. In a perfect world, a woody biomass plant would be growing trees and crops and harvesting those. And yes, burning wood creates air pollution, and yes, it’s more pollution than wind or solar energy does. But, it produces less air pollution that burning coal and less air pollution than would be produce if the trees burned in a wildfire as they likely would.

As attitudes towards natural gas and coal continue to change, we will have to radically alter the way we produce energy. While there is no one magic solution that will replace any of our frequently-used nonrenewable energy sources, Minnesota has many practical solutions that will help contribute to an independent, carbon-neutral state. Woody biomass is an often-overlooked, excellent solution to both our energy and our environmental issues nationwide. It is vital that we make woody biomass utilization an integral part of Minnesota’s renewable energy portfolio.

Christine Lee grew up in Madison, Wisconsin and recently graduated from the University of Minnesota.