PHOTO: Douglas C. Pizac/AP Photo
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ROCK OF AGES: Oil shale is rock containing burnable oil.
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The Baltic state of Estonia has cultivated a
sophisticated and wired image ever since the Soviet
Union broke up over a decade ago—laptops are everywhere,
Wi-Fi availability is commonplace, and the country is,
after all, the home of Skype.
But this broadband brain is fed by a Victorian belly.
The national fuel is a pale brown stone called oil
shale. Estonia burns it for electricity in two massive,
Soviet-era power plants located in the border town of
Narva, cheek by jowl with Russia. One of the twin Narva
plants still sports a 15‑meter-tall Soviet hammer and
sickle on its brick face.
According to Dmitri Lipatov, the plant’s deputy
manager, shale supplies between 70 percent and 90
percent of the country’s electricity. This is the only
place in the world where “fire rock,” as it’s known
locally, is responsible for supplying such a large
portion of a nation’s power.
Because of oil dependence and climate change, a global
push for energy alternatives is on like never before.
Oil shale of the kind found in Estonia, formed by
ancient algae compressed over time, is one possible
alternative fuel: upon extraction, it can be pulverized
and burned like coal to drive electric generators. Some
day, indeed, the new oil shale technology coming online
here could help other countries reduce their energy
dependency at an acceptable environmental cost. But the
fuel’s recent history in Estonia, to be frank, is about
as dirty as it gets.
As you drive east from Tallinn along the Gulf of
Finland, just before the Narva plants’ 250-meter
chimneys thrust up over the horizon, dusty slag mesas
start to loom off the side of the road, nearly 100
meters high. Every year the burned shale produces some 5
million metric tons of ash, which is collected and piled
up behind a pale 30-meter-high levee about 1.5
kilometers from the plants. Water is used to pump the
ash into the inexorably growing field, so a
copper-alkaline wastewater and rain pond floats atop it:
it’s a surreal, brilliant blue-green chemical Caribbean,
full of potassium, sulfate, hydroxide, and zinc [see
photo, “No Fishing”].
That’s not all. Burning the shale also creates tons of
small airborne particles laced with heavy metals. Also
going into the air are nitrogen oxides, a potent
greenhouse gas, and sulfur dioxide, which causes acid
rain. Last year the Narva plants spewed close to 10
million metric tons of carbon dioxide and gave off
enough of the other pollutants to match the emissions
from Finland’s entire energy sector. And that’s an
improvement—during the Soviet era, the plants’ emissions
were three times as high.
PHOTO: Michael Dumiak
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NO FISHING: This enticing lake is actually a chemical
stew, formed from water used to pump waste ash.
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One answer to this environmental nightmare would be to
simply shut down the plants and import power from Russia
or Germany. But state-owned Eesti Energia, in Tallinn,
having metamorphosed from its sleepy old Soviet-era self
into an up-and-coming regional player, thinks it can put
a clean new shine on this rusty technology.
In the Eesti plant, there are now eight 200-megawatt
power units. Built in St. Petersburg’s Leningrad Metal
Works and stenciled with Cyrillic characters, each unit
looks like an overgrown car battery. Lipatov goes to
unit No. 8 and points to a towering tangle of shiny
pipes. Stretching far upward is the first of what will
be 16 new circulating fluidized-bed boilers, two to a
unit, which drastically reduce emissions from burning
oil shale. The technology was first developed by
Finland’s subsidiary of Foster Wheeler, based in
Clinton, N.J., 25 years ago. Now it is possible to
deploy it in the huge sizes needed at the Eesti station,
delivering much more efficient power generation and
yielding fuel cost savings of 20 percent.
Shale crushed into 6- to 10-millimeter particles is
fed into the bottom of the furnace, and as the mixture
burns, it is blown upward by air nozzles at a steady
rate until it exits the furnace into a “cyclone,” which
catches the larger unburned particles and sends them
back down into the furnace—a circulating loop. Because
of this recycling through the boiler, combustion can be
kept at lower, much more even temperatures, reducing the
amount of ash and emissions. Unit No. 8 also has more
efficient electrostatic precipitator filters.
Foster Wheeler overhauled the unit and one other at a
cost of US $325 million. It still makes the same roar as
its neighbors, but Lipatov points to nearby gauges which
show sulfur dioxide emissions at zero and nitrous oxide
emissions at 110 milligrams per cubic meter of ambient
air, well under the European Union limit of 200
milligrams per cubic meter.
This is not by any means environmental perfection.
Eesti Energia has to pay $20 million in variances and
pollution fines every year. There’s still the matter of
fixing the ash pool, which is planned for the next three
years, using new disposal technology. And as a new
member of the EU, Estonia soon will have to come into
compliance with tougher environmental rules, which will
not be easy.
The Eesti story does show, however, what some basic
investment and long-term thinking can do. “There is a
lack of energy in this region and a growth in power
demand,” Eesti director Ilmar Petersen says. “This is an
independent energy source: we must be happy we have this
source here, and we’re much more interested to use it
than look somewhere else.”