Carbon Capture
and Sequestration
(CCS)
is a long time
'green' dream.
More like a nightmare,
because CCS is:
(A)
Very expensive.
(B)
Technically difficult.
(C)
Likely to be a money loser
for investors, even if feasible.
Three Demonstration Projects:
(1)
There is only one power plant
in the world with partial CC:
SaskPower’s Boundary Dam
project in Canada, which began
operation in fall 2014 at a
CC only cost of $1.5 billion.
The plan was to convert
the coal fired generating unit #3
to CC, capturing 800,000
metric tons of CO2 annually
to sell for tertiary oil recovery
in Saskatchewan’s nearby
Weyburn oil field.
For 2017 and 208)
the average Unit 3
uptime was only 70%
(severe maintenance problems),
while the CC parasitic
electrical load has run about
30%, rather than the planned 25%.
On July 10, 2018 SaskPower
announced it would not be
expanding CC to units 1 and 2
as originally planned.
(2)
There is only one US
sequestration only
demonstration,
the ADM/DOE project
in Decatur, Illinois.
The plan was to sequester CO2
from ADM’s Decatur ethanol
operations (no CC problem)
in the brine filled Mt. Simon
sandstone formation 7000 feet
below Decatur.
The demonstration project
cost $208 million, with the
U.S. department of Energy
contributing $141 million.
The goal was 1 million tons
sequestered over 3 years,
at an injection rate of ~1000tpd.
That goal was never reached.
The injected CO2
reacted with the brine
to form mineralization
that slowly plugged
the sandstone injection sites,
necessitating ever more
injection wells.
In 2018 ADM announced
that it was delaying
its more ambitious
next phase despite
the neat little provision
(26 USC 45Q) tucked into
the February 2018 tax bill
providing an inflation indexed
$20/CCS CO2 ton tax credit.
(3)
A July 31, 2019 Forbes article
describes a zero net emissions
25MWe natural gas fired electricity
generating demonstration plant
in La Porte, Texas ( near Houston ).
It uses a new ‘Allam’ cycle,
where the effective turbine
working fluid is CO2.
The idea is to burn
the natural gas in a
high pressure
pure oxygen environment,
thereby preventing
a carbon capture problem.
The demonstration plant
plans to sell the resulting
pure CO2 either to industry
or for Texas tertiary oil recovery.
Startup was in June 2019.
The ‘Allam’ cycle was invented by
North Carolina startup Net Power.
Combusting natural gas
with pure oxygen requires
an air separation unit (ASU).
The demonstration plant
has its own cryogenic ASU,
meaning big compressors,
heat exchanger fans,
and lots of electricity
required.
Net Power claims the
25MWe demonstration plant
cost $140 million.
That implies capacity
costs of $5600/KW.
The demonstration plant
is 50MWth and 25MWe.
That means it runs at
50% thermal efficiency.
Net Power says
the parasitic ASU load
is planned to be 29%.
That means the plant's
maximum salable
electrical output
is only 17MW,
not the 25MW
meaning its
true capital cost
is $8235/KW,
not the $5600/KW,
as Net Power implied.