Very interesting. Lots of mixed reviews on making coal clean. This is the latest.
Technology to Make Clean Energy From Coal Is Stumbling in Practice
by Ian Austen
OTTAWA — An electrical plant on the Saskatchewan prairie was the great hope for industries that burn coal.
In
the first large-scale project of its kind, the plant was equipped with a
technology that promised to pluck carbon out of the utility’s exhaust
and bury it underground, transforming coal into a cleaner power source.
In the months after opening, the utility and the provincial government
declared the project an unqualified success.
But the $1.1 billion project is now looking like a green dream.
Known
as SaskPower’s Boundary Dam 3, the project has been plagued by multiple
shutdowns, has fallen way short of its emissions targets, and faces an
unresolved problem with its core technology. The costs, too, have
soared, requiring tens of millions of dollars in new equipment and
repairs.
“At
the outset, its economics were dubious,” said Cathy Sproule, a member
of Saskatchewan’s legislature who released confidential internal
documents about the project. “Now they’re a disaster.”
The
utility that runs the project, SaskPower, and advocates for carbon
capture argue that the setbacks are typical teething problems associated
with any new and complex technology.
“Over
time, as more companies, countries engage in carbon capture and storage
technologies, the price for everybody is going to come down,” Mike
Marsh, the chief executive of SaskPower, told a legislative committee in
January. “That will make it easier to employ.”
The Boundary Dam Power Station sits near a wealth of resources not far from the North Dakota border.
Hundreds
of years of coal reserves are buried under the ground nearby, virtually
eliminating transportation costs. And the mining creates employment in
an area with limited job prospects.
“It’s
a low-cost, stable supply,” Mr. Marsh said. “There’s a tremendous
opportunity in North America to continue to utilize coal.”
To
the utility and the provincial government, the process known as carbon
capture and storage seemed tantalizing when a review of the power system
began 11 years ago.
The
technology offered a way to stick with coal in a carbon-conscious era.
It was especially attractive in Canada, where rising emissions from the oil sands have more than offset reductions elsewhere, including Ontario’s abandonment of coal-fired electrical generation.
Through
the process, machinery would first remove most of the soot and ash from
the coal’s exhaust. The exhaust would then pass through a kind of
chemical called an amine that would snatch the carbon, in the form of
carbon dioxide, out of it. The gathered carbon dioxide, separated from
the amine, would be compressed, moved through pipelines and ultimately
buried underground.
Variations
of the technology have been used as far back as the 1920s. And small
demonstration projects have largely worked, including one in Norway that
opened in 2012.
Boundary
Dam, which received a major Canadian subsidy and opened in September
2014, was the first full-scale deployment of the technology to cut
emissions from burning coal. Saskatchewan picked a process owned by
Shell, encouraged by its history with petrochemicals.
At
the outset, the utility and the province said the project was working
as intended, capturing 90 percent of the plant’s carbon. It was the
equivalent, they said, of taking 250,000 cars off the road.
Environmentalists and politicians from around the world came to check
out Boundary Dam.
But
the success story disintegrated last November when Ms. Sproule, a
member of the opposition New Democratic Party, unveiled the confidential
documents in the provincial legislature. She wouldn’t identify the
people who provided the documents, although the government confirmed
their authenticity.
The
documents showed that the system was working at only 45 percent of
capacity. One memo, written a month after the government publicly
boasted about the project, cited eight major problem areas.
Fixing them,
it said, could take a year and a half, and the memo warned that it was
not immediately apparent how to resolve some problems.
A
chart covering the first year of operation showed that the system often
didn’t work at all. When it was turned back on after shutdowns for
adjustments and repairs, the amount of carbon captured sometimes even
dropped.
The
buoyant public remarks, Mr. Marsh said, accurately reflected the
company’s early assessment of the system. “We were very optimistic when
this plant came online,” he said.
Still,
he acknowledged that “there were a few statements that it was achieving
more than it had.” Mr. Marsh characterized many of the problems as
design issues, such as inadequate temperature control systems, rather
than fundamental flaws.
But
Boundary Dam has exposed a problem with Shell’s process when used with
coal exhaust. Despite the plant’s initial filtering, tiny particles of
ash still remain in the exhaust and contaminate the amine, reducing its
ability to grab carbon, Mr. Marsh said.
“Over
all, we are pleased with the performance of the capture technology,”
Shell Canada said in a statement, adding that it was working with
SaskPower “to optimize operations and capture any lessons that can be
applied to improve future projects.”
But the costs are piling up.
One
shutdown last spring to clean and replenish the chemical cost 17
million Canadian dollars. Mr. Marsh said that the company was still
looking for a way to prevent the contamination.
The
repeated shutdowns have caused SaskPower to miss multiple carbon
dioxide deliveries to Cenovus Energy, the Canadian oil company that
signed a 10-year contract with the utility to buy most of the gas.
(Cenovus uses carbon dioxide to force oil from largely depleted wells.)
SaskPower has had to pay 7 million Canadian dollars in penalties,
offsetting most of the 9 million Canadian dollars in payments received.
On
top of that, the carbon system is a voracious consumer of the
electricity generated by Boundary Dam, which has 150 megawatts of
capacity. Mr. Marsh testified that about 30 megawatts of capacity were
consumed by the system, and an additional 15 to 16 megawatts were needed
to compress the carbon dioxide.
Tim
Boersma, the acting director of the energy security and climate
initiative at the Brookings Institution, said that extensive power loss
is a significant factor keeping other utilities from following
SaskPower’s lead.
“That is exactly the reason this is not going to fly,” Mr. Boersma said. “The plant’s efficiency goes down so dramatically.”
As
it continues to sort out the plant’s problems, SaskPower is damping
expectations. The utility cut its emissions reduction target for this
year to 800,000 metric tons, from one million.
The
company said it is working with the engineering firm that designed the
project to solve the problems and increase efficiency. Mr. Marsh said
there were indications that performance was improving. Last month, the
utility said the system was working at 67 percent of capacity.
Even some environmentalists are hoping for a turnaround.
George
Peridas, a senior scientist with the Natural Resources Defense
Council’s climate and clean air program, said his group did not endorse
the use of coal, but it accepted that coal would continue to be part of
the energy mix.
Carbon
capture, he said, will be a “vital part” of reducing emissions. Based
on discussions with SaskPower, Mr. Peridas said he was confident that
Boundary Dam would eventually work out.
“I don’t see any indication that the carbon capture system of this plant is broken,” Mr. Peridas said. “It’s had a bumpy start.”
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