Using Energy More Efficiently

  • The Sappi paper mill in Cloquet Minnesota produces most of the electricity it needs, using steam that also powers the industrial process. Sappi can even sell power when demand is high. Electric co-generation is enjoying a come-back. (Photo by Stephanie Hemphill)

More and mores states are establishing a “renewable energy standard”
for their electric utilities. So far, wind power is producing the bulk
of renewable energy. But there are other sources. Some are brand new.
Others have been around for a long time. Stephanie Hemphill reports:

Transcript

More and mores states are establishing a “renewable energy standard”
for their electric utilities. So far, wind power is producing the bulk
of renewable energy. But there are other sources. Some are brand new.
Others have been around for a long time. Stephanie Hemphill reports:


The first thing to know about electricity is that making it can be
incredibly inefficient.


In a conventional power plant, burning fuel turns water into steam.
The steam drives a turbine, which spins the generator. Only about a
third of the energy in the original fuel is converted to electricity.
Two thirds goes up the smokestack in the form of heat.


“Every time you convert energy from one form to another, you lose
something. That’s just the way it is, ’cause nothing’s perfect.”


Dwight Anderson works for Minnesota Power. He’s lived with that
inefficiency for his whole working life. Now, he’s trying to wring
more electric power out of every bit of fuel.


He’s high on something called co-generation. The basic idea is to
harness the heat or steam that normally goes up the smokestack.
There’s a good example of co-generation at the Sappi paper mill in
Cloquet, in northern Minnesota. Like many paper mills, Sappi makes
most of the electricity it needs.


Engineering Manager Rick Morgan points to a mountain of wood chips:


“We have about 20,000 tons of biomass stored.”


That’ll last less than a month. The plant uses 53,000 watts, enough to
power a small city.


Inside the sprawling buildings, there are several electric generators.
One of them is fueled by a recovery boiler, which burns the byproducts
of the paper-making process, to run steam through a turbine.


“…The actual turbine is manufactured in Czechoslovakia and the generator’s
made in Vestros, Sweden.”


Higher pressure steam spins the turbine to produce electricity. The
waste steam from the same boiler goes to the pulp dryer, the paper
machines, and other parts of the process.


Back in his office, Rick Morgan says energy is the fourth largest
expense for paper mills:


“If you can’t control energy costs in this business, you can’t be in
business.”


The main product here is paper, but sometimes Sappi sells electricity
too. That happened during a recent cold snap:


“The electric demand increases and the costs go higher and higher, to
the point that it’s financially feasible for us to generate power for
Minnesota Power.”


Opportunities to produce electricity turn up in some surprising places.
Like along natural gas pipelines. The pressure has to be boosted
periodically as the gas travels through the pipe. Compressors fueled
by the natural gas do that work, and normally they vent off waste heat.


But now in South Dakota, the waste heat is fueling small power plants.
They look like the barns and silos of a farm. The generator itself is
about the size of a truck.


Basin Electric Power Coop spokesman Daryl Hill says the plants are
owned and operated by an Israeli company, and the co-op buys the power:


“We get basically 22 megawatts of baseload for little investment.”


Other countries are leading in these approaches because their fuel
prices have been so high. As prices go up in the U.S., power producers
are finding ways to use more efficient technologies, and they’re
returning to old-fashioned ideas like combined heat and power. This is
a form of co-generation that was once common across the country.


A central electric plant uses its waste steam to heat buildings. Of
course, most people don’t want to live next to a coal-fired power
plant. But Neal Elliott, with the American Council for an Energy-
Efficient Economy, says with combined heat and power, cleaner fuels,
like natural gas, can become competitive:


“Use natural gas, but use it much more efficiently. And instead of
throwing more than half of the fuel value away, let’s do it with co-
gen.”


Elliott says combined heat and power and other forms of co-generation
could provide 20% of America’s electricity needs, and save on heating
fuel at the same time. And he says recovered energy generation like
along the natural gas pipelines could provide another 20%.


For the Environment Report, I’m Stephanie Hemphill.

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Easing the Ash Borer’s Financial Bite

  • Homeowner Frank Wydra watches as logs from 16 of his ash trees get turned into lumber. All of the ash trees close to his house had to be cut down after they became infested with emerald ash borers. (Photo by Rebecca Williams)

Homeowners and cities are losing many of their big, beautiful shade trees. An invasive insect called the emerald ash borer is killing ash trees in Michigan, Ohio, and Indiana… and making neighboring states worried. About 15 million ash trees are dead or dying, leaving behind enormous bills. The GLRC’s Rebecca Williams reports some people are trying to ease the loss by salvaging lumber from their dead trees:

Transcript

Homeowners and cities are losing many of their big, beautiful shade
trees. An invasive insect called the emerald ash borer is killing ash
trees in Michigan, Ohio, and Indiana… and making neighboring states
worried. About 15 million ash trees are dead or dying leaving behind
enormous bills. The GLRC’s Rebecca Williams reports some people are
trying to ease the loss by salvaging lumber from their dead trees:


(sound of birds chirping)


The emerald ash borer ruined Frank Wydra’s summer plans. His 10 acre
lot is full of ash trees… more than a hundred. Wydra built an
elaborate shade garden underneath a cluster of ash trees, right next to
his brand new house. Right around the time he and his family were
ready to move in… they noticed the trees were looking sick.


“They were here when we bought the property and we sort of built the
property, the house around these trees. I had no alternative but to
cut these down, because they were so close to the house.”


Wydra says he’s losing a lot more than a shady backyard. He says the
emerald ash borer is costing him at least 10-thousand dollars. That’s
the cost for cutting the trees down, grinding the stumps out… and
planting new trees. But there’s one part of that cost he’s not too
upset about: the 100 dollars an hour he’s paying to have his dead ash
trees milled into lumber.


(sound of portable sawmill at work and running under)


“It’s got a very close grain that allows you to mill it without too
much trouble. It’s nice stuff. I wish I hadn’t built all my
cabinets.”


Frank Wydra’s already got more board feet of ash piled up here than he
knows what to do with. But he says he’d rather pay to have the logs
turned into something he can use than pay to have them hauled away.
Wydra hired a company called Last Chance Logs to Lumber. Chris Last
brings his portable sawmill to sites like this one, and with some help
from his family members, he loads the logs onto the sawmill and slices
the bark away.

(sound of rolling logs under)

“We’re required to take at least a half inch below those two layers,
you’ll see as we open this up… just the characteristics of the log will
determine that… usually we take off more than that.”

By stripping away the bark and a half inch of the wood beneath the
bark, Chris Last is making sure none of the emerald ash borers will
survive.
Researchers have found that carefully debarking ash logs is one way to
make the wood safe to use.

Chris Last created his business four years ago, shortly after the ash
borer was first identified as the pest killing trees in the upper
Midwest. Since then, he says some of his customers have gotten pretty
creative.

“The neatest thing is a gentleman that was an architect, when he had
the tree cut down he left the log standing for about 10 feet, and what
he ended up building was an old English cottage house on top of this
stump. I guess he reads up there, but it’s beautiful, it’s absolutely
gorgeous, every bit of it, every stick is made out of ash.”

Last says he’s seen a church craft new pews from their ash trees, and
he’s worked for cities that have built picnic tables from ash, but for
the most part, homeowners and city officials are just starting to
figure out how to use the lumber from their dead trees.


Jessica Simons is with the Southeast Michigan Resource Conservation and
Development Council. It’s a nonprofit group that’s giving out grants
to promote the use of ash wood. Simons says the idea’s catching on,
but there are some real obstacles.


“To be honest, it can be a tricky proposition. What’s easier: go to
Lowe’s and buy lumber, or to have your dead trees removed, hire a
sawmill, have the mill come out, allow wood to dry and then be able to
finish it into a product.”


But Simons says milling ash trees into lumber can sometimes save money.
Right now, most homeowners and cities chip up their dead trees and have
the chips hauled away. Both of those steps cost money. Simons says by
milling trees on site, you can cut back on the disposal costs and end
up with wood for a new dining table or a bunch of park benches.

Jessica Simons points out that not all parts of the ash trees can be
turned into products. She says most of the ash wood waste from
Michigan and Ohio gets trucked up to a co-generation plant in Flint,
Michigan, where the wood chips are burned to generate electricity.
Simons says that is a good use for the lower-value parts of the trees,
like stumps or branches.


“But the only thing we’ve argued throughout this is that a number of
great logs were in that wood as well, and when you think about the
value that wood can have as lumber or a higher value product like a
railroad tie, it’s worth much more than what a truckload of fuel is
worth.”


Simons admits re-using dead ash trees won’t cut back a lot on the
tremendous costs that homeowners and cities are bearing to deal with
the ash borer, but she argues that turning ash trees into flooring or
furniture could generate a little bit of money instead of just adding
another line onto the bill.


For the GLRC, I’m Rebecca Williams.

Related Links

EASING THE ASH BORER’S FINANCIAL BITE (Short Version)

Millions of ash trees are being killed by a tiny green beetle called the emerald ash borer. Some people say all those dead trees shouldn’t be considered waste, so they’re recycling the trees into lumber.
The GLRC’s Rebecca Williams has more:

Transcript

Millions of ash trees are being killed by a tiny green beetle called
the emerald ash borer. Some people say all those dead trees shouldn’t
be considered waste, so they’re recycling the trees into lumber. The
GLRC’s Rebecca Williams has more:


Most of the time, when cities cut down their dead ash trees, they chip
up the trees and have them hauled away. Some people are trying to find
uses for the lumber from the trees instead.


Jessica Simons is with the Southeast Michigan Resource Conservation and
Development Council. It’s a nonprofit group that’s giving out grants to
promote the use of ash wood. Simons says cutting ash logs into lumber
can sometimes save cities money, because they can cut back on the cost
of chipping up and hauling away the trees:


“They’re also aren’t paying for lumber for other city projects because
they’re just paying for that wood to be milled and then they have all
the wood they need for projects like park benches or picnic tables or
sideboards for their trucks.”


Simons says because it’s a relatively new concept some cities have had
trouble finding room to store all of the lumber they’ve made from the
trees, but she says the idea’s still starting to catch on, as cities
look for ways to cut costs.


For the GLRC, I’m Rebecca Williams.

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