The Institute for Energy Economics and Financial Analysis (IEEFA) just released a report condemning blue hydrogen. They released a report in 2022 condemning CCS that was biased and strongly criticized, and this report should be regarded similarly. While this organization may seem to be scientific, I contend as I have before that their science, while intriguing, is often biased. The stated goal of the organization is to accelerate the energy transition, apparently by any means necessary, except any that include mitigating fossil fuel emissions.
According to devex.com:
“The Institute for Energy Economics and Financial Analysis (IEEFA) conducts research and analyses on financial and economic issues related to energy and the environment. The Institute’s mission is to accelerate the transition to a diverse, sustainable and profitable energy economy.”
“The Institute for Energy Economics and Financial
Analysis receives its funding from philanthropic organizations. They gratefully
acknowledge their funders, including the Rockefeller Family Fund, Energy
Foundation, Mertz-Gilmore Foundation, Moxie Foundation, William and Flora
Hewlett Foundation, Rockefeller Brothers Fund, Growald Family Fund, Flora
Family Fund, Wallace Global Fund, and V.
Kann Rasmussen Foundation.”
Most of the
above foundations are big funders of environmentalists and basically IEEFA
should be considered to be by extension an environmentalist organization, perhaps
more equivalent to Sierra Club and the NRDC, more so than say Environmental
Defense Fund, which is somewhat less biased against fossil fuels and willing to
admit and engage with making them less emissions intense rather than focusing directly
on their demise.
It is suggestive
by the rather aggressive title of the paper - Blue Hydrogen: Not Clean, Not
Low Carbon, Not a Solution: Making Hydrogen from Natural Gas Makes No Sense
- that includes 3 “Nots” and a “No” that the report is leaking bias. Since the group's name suggests it is a group of scientists and social scientists and one would assume
that scientists are unbiased, the title itself is a kind of red flag. As I do
see IEEFA papers highlighted in power and energy information hubs like Utility
Dive and in news stories, I think their conclusions should be scrutinized,
especially as they make these bold assertions and condemnations. Below I will
examine their conclusions and attempt some rebuttals.
The paper has
four key takeaways:
1)
The U.S. underestimates methane emissions
from the upstream through the downstream oil and gas sector. While that
may be true for a few areas, it is probably not true on the whole or on
average. In addition, oil & gas methane emissions are continuing to drop
throughout the U.S. in all sectors of oil & gas. It is certainly not true in
two of the main areas of planned H2 projects – Appalachia and the Haynesville
Shale region. There the model assumptions are right on.
2)
The U.S emphasizes the global warming potential
of 100-year CO2equivalent emissions when it should emphasize 20-year CO2eq
emissions. It is often stated that methane has a GWP of 84 times that
of CO2 in the near term. While it is true that methane has a higher GWP in the
near-term we should consider how long the near-term is. A caveat to that
statement should be the fact that methane does not persist in the atmosphere: “According
to MIT Climate Portal, methane lasts in the atmosphere for about a decade on
average, while CO2 can persist for centuries. Source: MIT Climate Portal. 2:
According to NASA’s Vital Signs of the Planet, methane has a relatively short
lifespan of 7 to 12 years in the atmosphere, while CO2 can persist for hundreds
of years or more. Source: NASA.” 10 years from now or maybe sooner all the
methane that leaked into the atmosphere will be gone while much of the CO2 will
remain for an additional 100-300 or more years. That means in order to get a
GWP equivalency we have to consider that the methane emitted in say 2013 is now
no longer present but the CO2 emitted in 1913 is still largely present. The
higher near-term GWP of methane has led to more emphasis on these emissions as
a way to mitigate climate change but that mitigation too will be in the near term. In explaining why we use 100-year equivalencies, MIT scientists put
it this way: methane does its damage quickly but soon fades away, while CO2
traps a smaller amount of heat consistently, decade after decade. Another
thing we should consider is that the U.S. is not one of the top 3 global methane
emitters. China, India, and Russia each emit more methane than the U.S.
3)
They note that hydrogen does have an
effect on global warming when it enters the atmosphere. While the EPA
notes that the GWP of hydrogen is 0 and this is true, it does indirectly affect
increase global warming by combining with other molecules in the atmosphere to
make and/or retain greenhouse gases, mainly methane, ozone, and also water by
reacting with hydroxide ions in the reaction H2 + OH = H2O + H. It can also
react with nitrogen oxides and VOCs.
Thus, hydrogen can be considered
to be an indirect greenhouse gas. Studies suggest that its GWP is about 20%
that of CO2 over the standard 100-year period. A June 2023 paper in Nature
Communications Earth & Environment came up with a GWP for hydrogen (indirect)
of 11.6 (+- 2.8). The paper suggests that previous studies did indeed
underestimate the indirect effects of fugitive H2 by about half. Since H2
reacts with other greenhouse gases, it is unclear if the changing of those gases
was subtracted out or not. I am guessing they were. While not a direct
greenhouse gas hydrogen does change the abundances of the greenhouse gases
methane, ozone, and stratospheric water vapor, as well as aerosols. The effect
on aerosols is much less than the other three. The graph below shows the relative
effects on methane, ozone, and stratospheric water vapor.
In any case, there is likely some truth to
this assertion that could bring down the benefits of blue hydrogen a small amount but these
quantifications are still in the early stages and more research is likely needed.
One of the biggest uncertainties is how much H2 is taken up by the soil as soil
is a known H2 sink. While the benefits of blue hydrogen may have been
overestimated a bit, pending a better understanding of leakage rates now and in
the future, that overestimation (even with their own conclusions) is not enough
to change the fact that producing and burning blue hydrogen reduces emissions significantly
over burning methane, even if there are new possible leakages to consider.
Hydrogen is a very small molecule so it does have the ability to leak. However,
as I have argued before, the best places to develop H2 projects are very near the point of use so that leakage rates and compression costs will be minimized.
They can be placed very near power plants where they can be blended in as
needed. This makes economic and emissions sense.
4)
They contend that CO2 capture rates will
not be as high as predicted. I think they may be way off the mark here.
They make comparisons with projects like the Petra Nova coal plant CCS project
where carbon was captured by retrofitting onto an old coal plant flue system. Hydrogen
synthesis is done at high pressure, which makes it much easier to get a higher capture
rate than from a thermal power plant flue which flows combustion gases at low pressure.
As I understand it, carbon capture rates for steam methane reforming (SMR) and autothermal
reforming (ATR) are very high, about 90% with SMR and 97-98% with ATR. That is
based on a webinar with an Equinor executive in early 2022. I see that the DOE
models they are giving have SMR capture rates much higher than 90%. ATR also
requires oxygen which must be sourced and delivered. Some could come from
nearby green hydrogen production since it is a byproduct of making hydrogen
with electrolyzers. It may also be an obtainable byproduct of nearby industries
as it is in some H2 projects. It is estimated that 5-10% of the energy in the
produced hydrogen will power the CCS system and another 5% would more than
cover any upstream methane emissions, especially in areas like Appalachia where
natural gas is very inexpensive and upstream methane leakage rates are
typically 1% or less. Thus a total of 10-15% (probably closer to 10%) of the
energy in the hydrogen would cover emissions and running the CCS system. That
would mean for an SMR blue hydrogen system in the Appalachian region, at a 90%
capture rate, the result would be about an 80% reduction in emissions before considering
the possible effects of any leaked hydrogen.
The IEEFA paper makes model conclusions
based on 20-year GWPs and 2.5% methane emissions rates, although they do include
1% emissions rates and 100-year GWPs as well. The list of methane emissions
studies by basin that they give includes two studies from the Appalachian Basin
Marcellus that do have very low emissions rates as verified but many others
from predominantly oil basins, mainly the Permian and the Bakken, that due
partly to flaring have much higher emissions rates and the gas from those
basins is associated gas, or gas that comes in addition to oil production. No
studies come from the Louisiana Salt Basin Haynesville Shale which also has low
emissions similar to those of Appalachia. While some hydrogen projects may come
from the Permian Basin and the Western Gulf Coast Basin Eagle Ford Shale region,
most are likely to come from the Appalachian and Haynesville regions, where gas
is abundant and cheap, and there is abundant nearby industry and power plants to
utilize the hydrogen. Thus, the baseline given as the default methane emissions
rate of 1% is likely to be much closer to most of the reality than the 2.5%
that they favor. They base this on the largely discredited calculations of
Cornell’s activist scientist Robert Howarth, who calculated a U.S. average of
2.6% and a mean of 3.5%. It should be pointed out that these methane emissions
determinations have the most influence over their conclusions, much more than
the 20-year CO2eq GWP, the carbon capture rate variances, and the H2 leakage
effects. Thus, the biggest debunk here is their use of inaccurate methane emissions
rates.
In determining capture rates for H2
projects they only consider older, past H2 projects, some with CO2
sequestration issues that rendered capture rates lower than planned. While that
could also happen with some newer projects, it is more likely that modeled
capture rates will be achieved, if not immediately, then in time as issues are
worked out. Some of those older projects were not designed for maximum capture rates, and new and better technologies are available now.
IEEFA uses the DOE clean energy standard emissions
rate of 4 kgCO2e/kgH2 as a line on their graphs. Below the line meets that
standard but it should be noted that this is just an arbitrary line. While it
is absolutely true that emissions intensity depends on methane emissions rates,
carbon capture rates, hydrogen leakage rates, and at least in the near-term on the
higher near-term GWP of methane, even at those somewhat higher emissions intensities
that they claim, these projects are still likely to mitigate emissions quite
significantly at reasonable costs. Even if one were to assume 85% capture rates
and 2.5% methane emissions with the emissions more than tripling the reductions
in emissions are still significant. Even so, I tend to favor the direct use of
natural gas over hydrogen due mainly to cost issues and logistics. I favor blue
hydrogen for cheap gas areas like Appalachia at locations very near point-of-use,
as little transport and storage as possible, and so-called turquoise hydrogen
through techniques like methane pyrolysis that can be integrated with
renewables. Some can even produce usable carbon products like carbon black so
those are CCUS but direct CCS projects are fine too. I am not overly bullish on
hydrogen, except perhaps geologic hydrogen if it were found in abundance, so I may
actually have some agreement that blue hydrogen is not a solution per se. It
is just one tool among many. Due to cost blue hydrogen is much more feasible
than green hydrogen.
Overall, my qualms are mainly with the
methane emissions rates and a bit with the insistence on near-term GWPs and
capture rates. I think they are dead wrong about the methane emissions rates
they prefer, are a little off on GWP emphasis although it should be considered,
and probably off on the carbon capture rates, or at least will be soon enough.
They may be correct about H2 leakage but the jury is still out and I think synthesis
near the point of use will keep leaks to a minimum.
References:
Blue Hydrogen: Not Clean, Not Low Carbon, Not a Solution: Making
Hydrogen from Natural Gas Makes No Sense. David Schlissel and Anika Juhn. Institute
for Energy Economics and Financial Analysis. September 2023. Blue
Hydrogen Not Clean Not Low Carbon_September 2023.pdf
Institute
for Energy Economics and Financial Analysis. Devex.com. Institute
for Energy Economics and Financial Analysis (IEEFA) | Devex
Why do
we compare methane to carbon dioxide over a 100-year timeframe? Are we
underrating the importance of methane emissions? Andrew Moseman and Jessika Trancik. MIT
Climate Portal. Why
do we compare methane to carbon dioxide over a 100-year timeframe? Are we
underrating the importance of methane emissions? | MIT Climate Portal
A
multi-model assessment of the Global Warming Potential of hydrogen. Maria Sand,
Ragnhild Bieltvedt Skeie, Marit Sandstad, Srinath Krishnan, Gunnar Myhre,
Hannah Bryant, Richard Derwent, Didier Hauglustaine, Fabien Paulot, Michael
Prather & David Stevenson. Nature Communications Earth & Environment
volume 4, Article number: 203 (2023). A multi-model
assessment of the Global Warming Potential of hydrogen | Communications Earth
& Environment (nature.com)
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