Biobutanol: A Viable Biofuel with Advantages Over
Ethanol as a Gasoline Additive
Intro
Biobutanol is butanol, or butyl alcohol, derived from a
biomass source. Butanol can also be made from hydrocarbons and that is known as
petrobutanol. As a biofuel, butanol has some significant advantages over the
most common biofuel, ethanol, or ethyl alcohol. As a C4 hydrocarbon biobutanol
is more similar to gasoline than to ethanol. Butanol has a lower vapor pressure
and a higher energy content than ethanol. Biomass feedstocks for biobutanol are
similar to those for ethanol, grains like corn, sugar beets, sugar cane, and other
biomass. There is also cellulosic butanol, like cellulosic ethanol, made from
plant wastes. Biobutanol can also be enhanced by bacteria, yeast, or fungi, and
made from algae as a feedstock with cyanobacteria. More specifically,
genetically modified bacteria offer some future possibilities for biobutanol
production. One challenge for biobutanol is that more bioethanol than biobutanol
can be produced from a bushel of corn. Biobutanol has been in development as a
modern biofuel for many years now and has fluctuated in value. More recently,
there are biobutanol gasoline blends in use for road vehicles in parts of the U.S.
Fermentation, Biosynthesis, Cyanobacteria, and Substrates
Biobutanol production relies on ABE fermentation - acetone-butanol-ethanol. One economic impediment to alcohol fuels like ethanol and
butanol is that they are limited
by inefficient fermentation rates. Escherichia coli (E. coli) bacteria
is useful in the commercial production of biobutanol since in a genetically engineered
form it produces the highest yields of isobutanol of any microorganism. Isobutanol
is a second-generation biofuel that has significant advantages over ethanol. E.
coli is ideal as an isobutanol bio-synthesizer for other reasons as well:
it has been studied extensively, it is very manipulatable with genetic
engineering, and it has the ability to use lignocellulose (from agricultural waste)
to make isobutanol. The process still faces economic hurdles though. Bioreactors
are also susceptible to bacteriophages that may damage fermentation. Scientists
are trying to genetically engineer that susceptibility out of new strains.
Clostridia is another bacterium that can make
isobutanol. It is very good at making isobutanol from cellulose. It was once used
to make acetone form from starch. Acetone was made from corn starch and
molasses in both World Wars in biobutanol plants through such fermentation. The
acetone was used in the manufacture of smokeless gunpowder and rocket propellant,
but butanol was still the main product. In the 1960’s it began to be more
economic to make butanol from petroleum products. Other potential bio-synthesizers
of isobutanol include the bacterium Bacillus subtilis, the yeast Saccharomyces
cerevisiae, and the soil bacterium Ralstonia eutropha.
Genetically engineered cyanobacteria, a form of algae, are
also a good feedstock for isobutanol. It does not require the use of plants. It
grows faster than plants. It grows in water and sunlight and takes CO2 from the
atmosphere, a climate plus. Drawbacks are a need for specific wavelengths of
sunlight and a medium of precise salinity, two conditions which are difficult
to control. Cyanobacteria bioreactors also require more energy to operate. These
energy intensity, salinity, and sunlight requirements impact the economics of
making isobutanol from cyanobacteria.
Metabolic engineering is used to allow an organism to use a
cheaper substrate. Fermentation requires sugars as a substrate so cheaper sugars,
like glycerol instead of glucose, could make the process cheaper. Glycerol is
cheap and abundant as a waste-product from biodiesel production. Other
processes are being explored to recover butanol with higher efficiency. Enzymes
are used to catalyze reactions. Fermentation chemistry and genetic engineering
are two technologies used to make fermentation more efficient and the search is
ongoing to find the most economic components for catalysis and for substrates.
The Timeline of Microbial Biobutanol Production below is from the Ph.D. dissertation of Reyna Gomez-Flores at the University of Western Ontario, 2018
Projects
DuPont and BP have a joint venture to develop, produce, and
market next-generation biofuels. Biobutanol is a big part of that. Swiss
company Butalco is exploring biobutanol production that uses a fungi to convert
organic waste into biobutanol. There are also plans for an E85B fuel mixture
that is 85% ethanol and 15% butanol to be run in existing E85 engines. BP and
DuPont claim that a 10% biobutanol blend with gasoline is possible with no
engine modification.
Th U.S. Coast Guard began a year-long engine test of 16.1 % biobutanol
blended fuel for ships in 2012-2013. At the time the price of oil was high. They
chose biobutanol over natural gas, ethanol blends, and biomass liquid fuels based
on maturity, performance, safety, and logistics. Their supplier used metabolic
engineering to develop yeast-based isobutanol. They were also doing engine
tests where they were running engines on the biobutanol regularly for months
then tearing the engines apart to analyze for corrosion and other issues. I don’t
know the results of this project but I can make a guess that cost is still an
issue relative to current oil and gasoline prices.
Eastman Chemical Company also had a biobutanol project in
the works in 2012, utilizing a genetically engineered Clostridium
bacterium for biosynthesis. Bioacetone and biobutanol made by the process are
used in coatings, molded plastics, and personal care products.
Biobutanol is also promising as a biofuel for use as jet
fuel. However, like some other biobutanol and other biofuel applications, there
is still economics relative to fossil hydrocarbons, so significant subsidization
is also required for profitability. Aviation biofuel does qualify as a non-CO2
emitting fuel but there has been difficulty in applying it to the EU’s Emissions
Trading Scheme (ETS) at least as of 2016.
Two companies manufacturing biobutanol in the US, Butomax and
Gevo, have had some patent disputes in the past. The companies also make by-products
including solvents/coatings, plastics, and fibers. This helps them diversify. Both
companies registered for “on-highway vehicle sales with EPA” by June 2018.
Biobutanol blends are currently sold in select parts of the U.S.
A more recent breakthrough in biobutanol production was recently announced in a new paper in the Journal of the American Chemical Society, This involves a new metal organic framework that can more efficiently separate or recover biobutanol from the fermented biomass broth. It removes a significant obstacle. Current focus is on scaling up the process.
Properties of Isobutanol that Favor it Over Ethanol
The energy density of isobutanol is 98% that of gasoline. It
does not readily absorb water from air like ethanol and so prevents corrosion
of engines and of pipelines. Ethanol that absorbs water can separate from the
gasoline with which it is mixed. Butanols, especially n-butanol, or normal butanol,
that has a slightly different chemical formula than its isomer, isobutanol, resist
such separation. It can be mixed at any proportion with gasoline – ie. it can
replace gasoline or be an additive to gasoline. Isobutanol has a high octane
rating similar to ethanol and so, like ethanol, is suitable as an additive to
boost octane rating. N-butanol has a lower octane rating and is not suitable
for this purpose. It can be made from plant matter not connected to food
supplies. Butanols are less damaging to engines than ethanol since they can be
mixed in at higher ratios before retrofitting or modification would be
required. This is because butanols have an air-fuel ratio and energy content more
similar to gasoline than ethanol does.
References:
Biobutanol, in U.S. Dept of Energy, Alternative Fuels
Data Center, Fall 2018
Researchers Make Key Advance Toward Production of
Important Biofuel – by Oregon State University, in Journal of the American
Chemical Society, accessed in Phys.org
Butanol Fuel, entry in Wikipedia
Biobutanol: The Next Big Biofuel? – by Jessica Ebert,
in Biomass Magazine, May 2008
Isobutanol to the Rescue: The U.S. Coast Guard is
Testing Isobutanol Gasoline Blends in its Fuel Engines – by Chris Hanson, in
Biomass Magazine, Oct. 25, 2013
The Business of Biobutanol: Acquisitions, Patent
Infringement Disputes Continue – by Erin Voegele, in Biomass Magazine, Jan. 9,
2012
Promising Jet Fuel Market Looms for Upgraded
Bioethanol, Butanol - by Kapil Lokare, in Ethanol Producer Magazine, Feb. 5. 2016
Biobutanol Production from Cellulosic and Sugar-Based
Feedstock from the Corn Plant – by Reyna Gomez-Flores. Ph.D. Dissertation, The
University of Western Ontario, in Electronic Thesis and Dissertation Repository, April 24,
2018
Racism, Sexism, Harassment, and Unfairness in the
Workplace
With the current national focus on racism I thought I would
write a bit about my own experiences. I’m a white male and below I relate some
experiences I have had, a reckoning of sorts. I am being quite candid here in
the spirit of providing accurate data through my own experiences.
While most of my work is remote and has been for more than
five years, at other times I have worked in offices, in the field, and attended
conferences, meetings, field trips, and workshops. Before my career in the oil
and gas industry I had worked many jobs, often working alongside African
Americans, Latinos, and people who migrated from other countries. Sometimes
they were co-workers and sometimes they were bosses. I had one job where I
worked alongside ex-cons repairing and refurbishing cable TV converters, some
black and some Latino. My supervisor was black and liked my work. I got called
into the office to talk to the higher up boss, thinking that I was going to get
my 15-cent per hour raise but instead I got fired. He said my work was lacking.
My supervisor was aghast. It was a lie. As it turns out, since I got hired a
few weeks before most of the crew I got fired before I had enough time in to
collect unemployment. Most of them too got fired a few weeks later. At another
job my boss was a very cool black biker. I don’t recall much racism in those
jobs but there was likely some I missed. Where I grew up there were very few
black families, but we were good friends with them. Two were classmates. However,
racism was there, in jokes, in comments, in inequality of opportunities.
In college I went to a school with a big international
population, so I had classmates from Africa, Indonesia, India, Europe, and all
over the place. There were Muslims and Hindus. I knew an interracial couple
there that had faced some backlash. One of my room mates had a black
girlfriend.
The oil and gas industry is perhaps notable, or at least it
was, for having few minorities. In the field at least, there were few women as
well. Drilling rigs had calendars up with naked or half-naked women. No one
thought much about it. It was quite rare to see a black or Latino man in the
oilfield in Appalachia. There were a few here and there. Some women would be
much talked about after they came and went. Later in office work we would be educated
about sexual harassment and policies around it and had to watch videos about
it. This was a good thing. People did tell crude quasi-sexist jokes, once in a
while. Consenting adults can do what they want to some extent I suppose, as
long as long as no one objects. I don’t recall anyone complaining about that. I
don’t recall much education about racism in the workplace though.
Racism in the office was rare, but there were certain people
who would make an occasional racist comment. After 9/11 I heard the word
“towelhead” a lot and the n-word on occasion. In places I heard Martin Luther
King Day referred to in derogatory language.
Most of the racist sentiments I encountered were in the
field. After Obama was in office for a while, I heard a Texas directional
driller say, “somebody ought to shoot that nigger.” There was a company man
from Oklahoma who used the n-word quite frequently. Luckily, he wasn’t around
long. There was one group of directional drillers and MWD guys that were openly
racist in their conversations. It was sad to hear one guy adopt derogatory
terms from them. In 2012 just after Obama was re-elected, I opened the door to
a DD/MWD shack and an old directional driller from Louisiana barked at me, “Did
you vote for that nigger?!” Interesting that they could feel so confident to
say such a thing without consequence. He sort of apologized and tried to
explain his use of the term but it was weak. He explained that once at a job a
black man put him in danger insinuating that that gave him a right to use
racist language.
Rig hands, aka “rough necks” were not known for political
correctness. Some liked to mess with people and intimidate people. I worked
with lots of them through the years. I actually faced what could be termed
sexual harassment from some though I knew it was a ruse and tended to ignore
them. A few guys took things to deep levels and would be willing to mess with
anyone. Once when I got to a well site at a rig I had never worked with before
I went to the doghouse and introduced myself and asked where I could plug in.
Some rigs were very particular about where to plug in. A rig hand asked if I
had ever worked at a drilling rig before, I said “well yeah.” He said. “then
act like it,” and walked away. This was in northern Ohio. Another hand there saw
my West Virginia plates and said “we don’t like people from West Virginia.” He
said one guy just got out of prison. He said they were going to slash my tires
and rape me. It was night. There was no one else around except them and me. I
went about my work, ignoring them. Then one put a pistil up to my head and said
he was going to blow my head off. I was writing down pipe tallies and just kept
on writing trying to ignore him. He said some more vile things and I went off
to my work trailer. I actually worked with that rig a few more times. The one
guy really tried to intimidate people. It was a ruse, sure, but a cruel one. I
confronted him about it and he said, “What are you a psychologist?” I was a
mudlogger then. There were tool pushers that didn’t like us mudloggers. Later,
as a wellsite geologist a Canadian tool pusher complained that I was going too
fast coming into location. I was going maybe 10 mph, but they had a posted
speed limit of 5 mph. Fair enough, but he didn’t have to threaten a sledgehammer
through my windshield! I think that was just for emphasis, though.
In the oilfields and in other jobs like construction there is
often a roughness around boss-employee relations. These jobs require people to
know how to be safe and putting others in danger is not tolerated. One problem
is people saying they know how to do something when they don’t know how to do
it. One time a rig hand thought he knew about drilling and when the driller
went off location for supplies. He decided to operate the rig controls and
messed something up. He felt bad about it and walked off. We were in the
mountains of West Virginia in the middle of nowhere. They found him hours
later. I’ve heard tool pushers be abusive to rig hands, company men and
drilling engineers be abusive to young geologists, and one tool pusher be
abusive to his girlfriend. I saw one driller drunk as hell on location, but his
co-workers were keeping watch on him.
I have kept my hair long for the last thirty years. In some
places men with long hair were/are discriminated against. Once I went to a
place to inquire about a job and the owner of the company told me that if I cut
my hair he might hire me but after subjecting me to religious proselytizing and
accusing me of being a drug addict. I decided I didn’t want to work for such a
fellow. One time on the way between two oilfield jobs I got pulled over for
speeding. I drove a lot then and was a bit of a “leadfoot” as they say. The cop
said he smelled marijuana, which is something I did not indulge in. Perhaps he
smelled some hydrocarbon on my work jacket, drilling mud or diesel oil I don’t
know. Another cop came. He said he smelled it too. They made me stand with both
hands on the hood of my car while they searched it. It was humiliating. Then
about 4 months later it happened again. The cop said he smelled marijuana. I
got a little huffy and said a bit loudly, “No you don’t.” He put his hand on
his gun and said, “You wanna get smart with me?” I said. “no sir.” Both times
I’m pretty sure I was targeted due to having long hair. That is a kind of
profiling. Even a few geologist colleagues had made jokes behind my back about
my hair, one joking we should find him asleep and cut off his ponytail.
Another police encounter involved me sleeping in my truck. In
those days we had a very small per diem and would rarely, if ever, get a hotel
room. I worked a 12-hour night shift and would have to sleep during the day. We
had no sleeping facilities then. You slept in your vehicle. However, in the
middle of summer when it’s hot it is hard to sleep in a vehicle during the day whether
the windows are down or not. On well locations there is no shade. One day I
went off and found a shady pull-off place along a quiet and quite isolated gravel
road and parked there for a bit. Obviously, many cars had parked there. I don’t
think it was private property. I decided this would be a great place to sleep
so I laid down in my truck seat there and went to sleep. I was in Amish country
in north-central Ohio and I had heard a few Amish buggies go by. Later I was
awakened by a bullhorn with the words, “step out of the vehicle with your hands
up.” That is not a fun way to wake up! Again, it was the out-of-state plates
that roused suspicion. The cop was quite rude to me and threatened to arrest me
for vagrancy.
Once when walking down the street in a Midwestern city on a
weekend night I was harassed. I had a t-shirt on that had a dragon and maybe a
Chinese symbol. I was walking past a group of African American men. A very
large one said, “My boy knows Egg Fu Yung” and pushed me hard enough to knock
me down. Instead I got knocked into one of his friends who pushed me away and I
stumbled on down the street. In the small town where I grew up there was one
strange guy known as a neo-Nazi. After having once gotten beat up by a group of
black men he unfortunately chose that avenue.
When I leave my house, I usually go by a neighboring farm
that has Trump flags and signs and a confederate flag. One will see quite a few
confederate flags in Ohio and West Virginia and even some in more northern
states. Now, they may claim a veneration for southern heritage but that is a
weaker argument for northern states. The popularity of the confederate flag
directly correlates to moves to counter the civil rights movement.
I don’t recall ever encountering racism at an oil and gas
meeting or conference. I do believe we are becoming a less racist and less
sexist society as a whole despite the ubiquity of much direct smart phone
evidence of bigotry. It is my guess and my hope that racism, sexism, and other
harassment in the workplace will continue to decrease.
I have been fairly well compensated for my work over the years,
but I did have one experience where I worked for a few months on a project without
receiving any compensation. That would qualify as an experience of unfairness.
I was recommended to a landowner who also owned a construction business to advise
on drilling a well on his property. He is a well-known owner of property and
businesses in the region. I agreed to do the work for a few hundred dollars and
a small overriding royalty interest in the well. I advised that it was a longshot
to make a good well but that it should make some gas. I did geologic mapping,
researched nearby well records, advised on zones, did gas detection during
drilling, picked perforation zones and attended the perforating, went over
hydraulic fracture design and attended the nitrogen frac job and some of the
flowback. I had written up a contact to be signed but it was never signed or
returned to me. The well was in a low-pressure area and may not have been fully
cleaned up and may have needed some compression. In any case, the well was either
plugged back or co-produced in a zone a few hundred feet higher. I got no
compensation at all and no explanation. I think he did pay for lunch once. My
business was booming at the time, so I didn’t worry about it.
Satellite Measurement of Methane Leakage and
Flaring: Comparisons of Vented and
Burned Methane: Oil Sector vs. Natural Gas Sector and Methane Mitigation Going Forward
Atmospheric methane has been measured continuously from
space since 2003, and new instruments have been put in orbit the last few years
to get more detailed measurements of point sources and regional sources. Future
satellite monitoring is expected to employ geostationary observations to get
higher resolutions in specific regions and to better understand daily
variations in methane output by natural sources like wetlands and manure. In
order to get more accurate quantification these efforts require comparisons
between top-down inverse analysis from satellite measurements and bottom-up construction
of emission inventories. However, since the Trump administration’s EPA pulled its
information request for companies to be required to develop their own methane
emission inventories through leak detection, the bottom-up inventories will only
be accurate for the companies that actually do it, which includes many of the oil
and gas majors and some independent operators who are perhaps anticipating that
the requirement will come back at some point.
In 2019 flaring of natural gas from oil wells in the U.S.
climbed to nearly 1.5 BCF/day, between 1.5 and 2% of all gas produced in the
U.S. The bulk of the flaring came from two regions: the West Texas/Eastern New
Mexico Permian Basin and the Bakken oil play in North Dakota. In addition to that,
combined methane leakage from upstream and midstream sectors, ie. from gas
wells, abandoned wells, pipelines, and facilities, is thought to be a similar
amount. However, that methane is not burned so it is significantly more potent
(in the short-term) than flared gas in climate effect. Downstream natural gas
distribution systems also leak methane at about 0.5%, so the total leaked from
the natural gas sector is a bit more than from the oil sector. At least that is
what the bottom up studies – adding predicted total emissions together –
suggest. Natural gas is dissolved in oil in varying amounts in different
hydrocarbon plays and fairways. Thus, natural gas also leaks from oil tanks,
condensate tanks, and other facilities. Quantifying how much leaks from each
sector and comparing is no easy task and requires a significant leak detection
effort. Flaring amounts are fairly well known in comparison.
A new estimate of total methane leakage collected from
satellite data over the Permian Basin indicates that actual leakage is more
than double what it was thought to be. This is concerning for several reasons.
Even though there is a bigger margin of error with satellite data, it is much
less than the increase. First it suggests that leakage is not being measured adequately
on the ground. Second it suggests that some companies could be venting more
than they say. Third, it suggests that this situation is not sustainable in the
long term.
Highest Rates Ever Recorded Over a Hydrocarbon
Field – Permian Basin
The newly estimated leakage rate from the Permian went from
1.2 teragrams to 2.7 teragrams. That would mean that 3.7% of total Permian gas
produced is leaking into the atmosphere. The new estimates come from a study by
Harvard atmospheric scientist Yuzhong Zhang as reported in the journal Science
Advances, with data obtained from the Tropospheric Monitoring Instrument,
on a European Space Agency satellite. Since flaring burns most of the methane
(98-99.8% typically) the data indicates that this is just leaking methane. The
same data over other hydrocarbon fields does not show high leakage rates. For example,
in the Appalachian shale gas areas the methane (including all sources:
wetlands, landfills, agriculture, and manure, etc.) is only elevated in a few
small areas which suggests that the low methane leakage rates reported in the
basin are close to accurate.
Methane Mitigation Going Forward
The following information comes from the Hart Energy article referenced below:
In 2019 Kairos Aerospace investigated methane leakage at 28,000 active wells and 10,000 mile of pipelines covering most of the New Mexico part of the Permian Basin. What they found was that less than 3% of the sites were leaking 70-80% of the methane. That is good news for mitigation. When companies estimate methane emissions they are relying on emission factor of their equipment rather than direct measurement. That means that their estimates are always going to be lower than the actuals. Finding out the causes for the bigger leaks is leading to real reductions:
"As an example, a client from the 2019 survey realized that a significant number of its large emissions were coming from a particular type of thief hatch that was not sealing properly."
Replacement of those hatches is expected to show significant reductions in emissions when the area is resurveyed.
"For one client, Kairos's work identified the root cause for a large portion of emissions was that line pressure was frequently too high in one of its midstream partner's gathering networks, causing venting (as intended) from the pressure relief valves on the tank batteries."
This type of emissions from gathering lines is more difficult to mitigate but can be prevented by better gathering design that reduces bottlenecks leading to high line pressures.
Another example involved a large crude oil gathering and processing facility where actual methane emissions were found to be much higher than estimated. Thus justified investing in a large vapor recovery system that will capture sellable product and allow the facility to stay within permitted emissions requirements.
Below is a graph of methane emissions by source from the Kairos New Mexico study:
Here we see that in the oil-rich Permian Basin most of the methane emissions are coming from well pad tanks 40% and gathering lines 30%. Dry gas areas such as much of (but not all) Pennsylvania do not have such tanks so that limits a major source of emissions compared to the oil fields.
Another very good hot off the press article in the June issue
of E&P magazine focuses on greenhouse gas emissions but mostly on methane
emissions. It gives some insight into evaluation and management and some very
interesting new technologies developed by service providers that are being adopted
by oil majors and independents. Below is a summary:
Companies may categorize methane emissions into two types: operational
– emissions that occur in accordance with equipment designs, and fugitive
emissions – mostly unintended leaks. They may require merging of data to assess
their own emissions sources effectively. Service providers specialize in such data
management. Operational emissions can often be reduced by replacement of equipment
with better equipment. Fugitive emissions most often must be detected and
repaired. There can be some overlap of operation and fugitive emissions for
example when a certain piece of equipment is leak-prone.
Another service provider specializes in developing a
GIS-based platform for mapping data involved in methane emissions management. The
company, Geosite, integrates different kinds of data like satellite imagery, sensor
locations, and drone data through map layers. This can be valuable in a number
of ways from characterizing emissions to aiding field ops in leak detection and
repair (LDAR) activities.
Flaring mitigation is another area where service providers
are offering different solutions. Flare mitigation often involves converting
the burning gas to electricity via gas turbine technology. The problem then often
arises that there are many point sources of power generation and no way to use
the electricity, especially in fields that are far from grids and power users.
One company offers a solution by using the flares to power high-usage data
center servers and computing applications like blockchain that are power
hungry. I’m not sure if they include the dubious and speculative blockchain usage
of cryptocurrency mining. Their process also involves building a grid to
connect the data centers together. Perhaps flares on several well pads could power
an electric frac job or provide power for drilling operations. I wouldn’t be surprised
if flares were adapted to charge batteries that could offer power regulation
and peak shaving for local power grids or some other distributed energy
application.
The Oil and Gas Climate Commission has a $1 billion fund to support
greenhouse gas reduction technology development. Part of that fund was used to
develop a technology to replace pneumatic controllers that run on compressed
methane which is vented in the process with pneumatics that run on compressed
air which is powered by burning natural gas or some other power source resulting
in a significant net reduction in greenhouse gas emissions. The company estimate
that pneumatic are responsible for 20% of methane emissions and that there are about
250,000 of such replaceable pneumatic devices in use in the U.S. which are responsible
for 14 million tons of CO2 equivalent.
A U.S. Oil-Producing Region is Leaking Twice as Much
Methane as Once Thought – by Carolyn Gramling, in Science News, April 22, 2020
Methane Destruction Efficiency of Natural Gas Flares
Associated with Shale Formation Wells – by Dan R. Caulton et al: Environmental
Science and Technology, 2014
Satellite Observations of Atmospheric Methane and
Their Value for Quantifying Methane Emissions – by Daniel J. Jacob et al., in Atmospheric
Chemistry and Physics, 16, 14371-14396, 2016
E&P Operator Solutions: Methane Measurement Understanding the Big Picture - by Ken Branson, Kairos Aerospace, in Hart Energy, May 28, 2020
Keeping a Lid On GHG Emissions - by Brian Walzel, Senior Editor, E&P Mag, Vol 93, Issue 6, June 2020
Logistical, Safety, and Environmental Issues of
Storing Excess Oil During This Oil Crash
With oil storage hubs nearly full and many more than usual full
tankers docked or in open ocean, storage solutions are actively being sought. The
main hubs such as the one at Cushing, Oklahoma are basically full. Plans to add
about 77MM barrels of oil to the Strategic Petroleum Reserve will help but are
not yet approved and it takes time to move that much oil there. The incentive for
storage companies is to buy oil at rock bottom prices and sell later at a significant
profit. But will there be costs to this storage overflow? Are these new and
makeshift oil storage facilities being managed adequately? Will there be spills
due to mismanagement? Will excess oil in storage above ground lead to more methane and VOC emissions?
The Texas Railroad Commission decided against mandatory production
curtailments as many companies are implementing voluntary curtailments. As long
as these makeshift storage facility owners are making storage available there
will be incentive to sell for those who must sell to survive. Oilfield water
storage tanks are being converted to store oil. Pipeline company Energy
Transfer LP is planning to fill their available pipeline capacity to store oil.
The return of oil demand in the near future is unlikely and
it could take a while before it moves much. Both road travel and air travel are
expected to stay down for the time being, especially air travel. Refineries do
not need it. In reality, the oil is safer in the wells but shutting in wells
can cause problems with the wells and add expense especially when resuming production.
There could even be reservoir damage. The International Energy Agency estimates that
global oil demand is down by a quarter. That also means that the announced
OPEC-plus production cuts won’t have the intended effect on prices. With real uncertainty
about re-openings of economies and planned gradual and careful re-openings,
demand is not expected to go near pre-coronavirus levels any time soon. Storage
overflow is expected to continue to be a problem even after some oil demand
resumes. Prices could collapse again to ‘negative on paper’ territory if production
is not slowed enough. The shortage in global storage guarantees it. A recovery
in the oil sector is not really expected till 2022 but in the meantime the level
and speed of demand return will dictate what happens.
Above ground and underground storage tanks, ASTs and USTs
respectively, are regulated at federal, state, and local levels. Spill
prevention, control, and countermeasure (SPCC) plans are required according to
the Clean Water Act (CWA). EPA and OSHA also have requirements for oil storage
management. Tanks must be made to certain specs. Those who operate transfer and
storage facilities also have training requirements dictated by regulators,
usually individual states, under EPA guidance.
References:
Wanted: Somewhere, Anywhere, to Store Lots of Cheap
Oil – by Rebecca Elliott, in The Wall Street Journal, May 11, 2020
The Hunt for Oil Storage Space is On – Here’s How it
Works and Why it Matters – by Sam Meredith, in CNBC, April 22, 2020
Breaking: Images of Fully Loaded Oil Tankers Stranded
At Sea – in Sahel Standard Magazine, April 29, 2020
Storage Tank Regulations – by Kaela Martins, Retail Compliance
Center, Retail Industry Leaders Association (rila.org), April 14, 2020
Oil Glut to Halve in May and Shrink to 6mbpd in June:
Rystad – by Carla Sertin, in Oil and Gas 360 (oilandgas360.com), May 3, 2020
The Absurdity of Attribution Science: Arguments Against the
Quantification of Blame
The headlines that say just 70, or 90, or however many
companies, are responsible for all the carbon emissions and should be somehow
punished show an ignorance and an anti-corporate bias. Of course, affordable
and readily available energy is the cornerstone of a successful modern economy
and society. That society demands affordable energy. Handicapping those who
provide it will not work. It will simply make that energy less affordable. That
is a good basic argument against large carbon taxation. The goal of carbon taxation
is to entice consumers to use less fossil energy. It should not be a means to
punish those who produce that energy. But it certainly can be.
One might say that since the advent of fracking in the U.S.
made electricity and gasoline significantly cheaper, then consumers should have
used their savings to buy renewable energy – rooftop solar and electric vehicles.
Some of us did but the overwhelming majority did not. Much of this is due to
the high initial investments required. This shows that due to cost renewable energy
will likely not be widely adopted without some sort of government requirement
to decrease the affordability of fossil fuels.
The attribution of blame for the carbon dioxide put in the
atmosphere is another example, this one being used by the IPCC and the UN in
attributing cost structure liabilities for different countries in the fight
against climate change. If blame is assigned value, then why not improvement?
The energy provided to cause those emissions triggered vast improvements in
human well-being. Should those not have a value put on them as well? I’m not
saying the whole valuation should be abandoned but that it should be reasonable
and not overly punishing to high-emitting countries. Often, such attribution,
is attribution of blame, and is used as a political tool. One reason the U.S.
is not so gung ho about the Paris Climate Accord is that the U.S. is punished
by having to pay a higher cost due both to its high historical emissions and
its high per capita energy use. That makes it very easy to group it as yet another
instance where a UN or world body requires the U.S. to pay proportionately more
than the Europeans and others. We pay more in other groups like NATO due to our
prosperity as payments often are set at % of GDP, while the Europeans more often
than us do not even meet those criteria. If the UN wants to get the US back in
the Paris Accord, then they should perhaps provide one clear incentive – a significant
discount – since some is better than none.
The governor of New Jersey has stated that he would like to
collect money from these flimsy bogus lawsuits against companies like Exxon for
covering up climate science – mind you, in times when climate science was not
even moderately well-established among actual climate scientists – and use it
to further harm them. The lawsuits are patently ridiculous and should not even
be heard. Several cities have stated that they would like to sue and use the
proceeds to shore up climate change preparedness. Of course, cities and states
are huge consumers of fossil fuels. Preparedness against weather events is a
good idea but making others pay for it is not.
Another issue is that of groups of youths being encouraged
to file lawsuits against fossil fuel companies for possible future harm from
their emissions. It is a waste of time and resources and mainly a political
ploy to increase pressure. The future of such litigation probably rests on
whether sympathetic judges can be found. Proponents of the suits like to
compare them to litigation against tobacco companies for advertising and promoting
smoking. But smoking is a choice and in contrast, use of energy is a basic
necessity.
The problem with this attribution science is that it is not
really science. It is rather a means of attributing punishment value and a
means of economic redistribution. Fossil fuels are distributed unevenly around
the world and those endowed with them should not be punished simply for developing
what they have.
Essentially, attribution science is like any risk assessment
where risk is evaluated and quantified. Of course, quantification of risk is
highly debatable and requires scientific experts to estimate accurately. In
these litigation examples it is often the highly biased accusers doing the
assessment, aided by sympathetic judges and some experts, usually outspoken and
arguably biased ones.
Overall, I think this so-called attribution science is a
trend that is not sustainable, at least the way it is being done by bias and
activism. It is unsustainable and not viable as it is tainted by ideology. Any
true attribution or quantification of risk and harm would need to be as
unbiased as possible, perhaps done via scientific council of diverse groups of well-respected
authorities rather than ideological and biased groups with an agenda to punish.
So far, sanity has been maintained, as most of theses climate
lawsuits have been thrown out. Likely, they will continue to be dismissed but
will some eventually get through with sympathetic judges and governments? Let’s
hope not. There are better ways to address the issue.
References:
Climate Change Lawsuits Collapsing Like Dominoes – by Curt
Levey, in insidesources.com, March 5, 2020
Big Oil and Green Energy: A Long History of Collaboration, Recent Moves,
and Allocating Capital as a Hedge Against Future Contraction in the Oil &
Gas Industry
Big Coal vs. Big Oil
The U.S. coal industry has been in a state of decline, a
state of contraction, for several years now. Bankruptcies are common, coal use
continues to decline, few new mines have been opened, and no new coal-burning
power plants are likely to be built in the U.S. While there is some occasional
export growth in metallurgical coal, thermal coal continues to stagnate and
that is very unlikely to change. There is little upside potential for coal
companies to transition into companies with cleaner portfolios. Aside from a
few vague and thus far uneconomic opportunities to do things like deriving rare
earth elements from coal mine tailings or coal ash or to use coal ash to make
high-strength carbon materials there is little upside potential for company transitions.
On the other hand, oil majors have long been investing in green tech and
renewable energy. Such investment has waxed and waned through the years as
company profits have risen and fallen. Exxon has been developing algae-derived
biofuels for many years. Exxon was also instrumental in the development of the
lithium battery, especially through the work of employee John Goodenough, who led
the research and development of lithium battery technology.
The Long History of Big Oil and Green Energy
Collaboration
In the recent book, The Wizard and the Prophet: Two
Remarkable Scientists and Their Dueling Visions to Shape Tomorrow’s World, author
Charles C. Mann notes that at one point in the 1970’s the two biggest developers
and utilizers of photovoltaic solar panels were the Pentagon and Big Oil. The
main uses were military satellites and powering offshore oil platforms. Indeed,
70% of all solar panels were bought and deployed to power those platforms. Thus,
the collaboration between Big Oil and green energy goes back about half of a
century. The following paragraph from the book is a good summary:
“Realizing that
solar had become essential to oil production, petroleum firms set up their own
photovoltaic subsidiaries. Exxon became, in 1973, the first commercial manufacturer
of solar panels; the second, a year later, was a joint venture with the oil
giant Mobil. (Exxon and Mobil merged in 1999.) The Atlantic Richfield Company (ARCO),
another oil colossus, ran the world’s biggest solar company until it was
acquired by Royal Dutch Shell, the oil and gas multinational. Later the title
of world’s biggest solar company passed to British Petroleum (now known as BP).
By 1980 petroleum firms owned six of the ten biggest U.S. solar firms, representing
most of the world’s photovoltaic manufacturing capacity.”
Much of the initial green energy investment by oil majors
was prompted as well by notions common at the time that oil was likely to run
out sooner rather than later. Peak oil production and resource depletion was a
serious concern in those times. Investments went up and down with the latest
reserve estimates as well as with the latest profits of the oil majors.
Revival of Green Energy Investment by Oil Majors, Particularly
European Oil Majors
Several of the multinational oil majors, particularly the
ones based in Europe, have indicated that they intend to move toward carbon
neutral operations by 2050. That plan includes more investment in renewable
energy companies as well as R & D. European oil and gas major in particular
have made recent acquisitions in solar and offshore wind. France’s Total has
controlling interest in major solar player SunPower and recently brought its renewable
energy portfolio to 5.1 gigawatts. BP, Galp, Eni, Equinor, Repsol, and Shell
also have large amounts of renewable assets. The biggest solar asset owner
outside of China is NextEra Energy with about 4.6 gigawatts but Total is
closing in with diverse solar assets spread across 15 countries. Total is
apparently focusing on solar in its goal to get 20% of its revenue from low
carbon businesses by 2040. Equinor is leading oil and gas sector investment in
wind, expected to be 4.6 gigawatts by 2025 while Shell projects 1.8 gigawatts
in wind investment by 2025. That would give Equinor and Shell about 6% of
global installed wind capacity by 2025. Total has also been moving into
offshore wind investment. Another collaboration is reviving the utilization of green
energy from onshore or offshore to power offshore oil platforms.
One reason European oil and gas companies have been
investing in renewables is shareholder pressure. Such pressure is less in the
U.S. so far but could increase. Companies like Exxon and Conoco are thought to
be readying for such a trend if it looks likely to happen. Aside from shareholder
demands, some form of carbon taxes could make oil and gas less profitable and
renewables more profitable so readiness could be important. Thus, in some ways
it could be seen as a hedge against possible future contraction in the
industry. With the coronavirus majorly impacting oil demand we can get a
glimpse of what a drop in oil demand can do and already the prospects are not
good. Oil majors may also hedge by focusing on downstream refining and
petrochemical production.
Big Oil and Renewable Energy R & D: New
Projects Include Green Hydrogen Development
Aside from investment in utility-scale solar, (mostly) offshore
wind, and associated infrastructure, there are a few other Big Oil R & D
projects worth noting. One is Shell’s project in developing so-called Green
Hydrogen. The project is only in feasibility phase but the plan is to develop
3-4 gigawatts of offshore wind capacity in the North Sea to power by 2030 to
make hydrogen, with dynamic, quick-start/quick stop, electrolyzers along the
coast of the Netherlands and offshore. Although less than 1% of hydrogen
currently comes from renewable energy that percentage is expected to grow quite
a bit this decade, eventually beginning to displace oil. If enough European renewable
energy is curtailed due to peak generation and peak demand imbalance then
prices for that excess drop. The dynamic electrolyzers could be set to quickly use
excess renewable generation, take advantage of low dynamic pricing, and help
wind and solar generators to sell excess at reduced rates rather than lose it. Hydrogen
can be stored in large tanks for later use, for industrial applications, or to
power fuel cells. However, in order for green hydrogen to be economic relative
to hydrogen made from fossil fuel, usually natural gas, the cost of renewables relative
to gas would have to drop by 2-3 times. That could happen by 2030 which would
be the bet. If carbon taxes get ratcheted up by then that is a pad for the bet.
Nonetheless, it is a risky endeavor at present. Even so, WoodMac notes that global
green hydrogen deployment, currently as 252 megawatts, is expected to grow to
3205 megawatts by 2025. That is a big jump. Economics are expected to improve by
2030.
References:
The Solar Industry’s New Power Player: Oil Majors – by Jason Deign, in
GreenTech Media, Feb. 26, 2020
Shell Exploring World’s Largest Green Hydrogen Project – by John
Parnell, in GreenTech Media, Feb. 27, 2020
The Wizard and the Prophet: Two Remarkable Scientists and Their Dueling
Visions to Shape Tomorrow’s World – by Charles C. Mann, (Alfred A. Knopf, 2018)
Could Green Hydrogen Become the New Oil? – by Stephen Lacy, in
GreenTech Media, Jan. 23, 2020
Energy Transition: The Future for Green Hydrogen – by Wood Mackenzie,
Oct. 25, 2019
Geographic Information Systems: Some History, Some Thoughts,
and What’s New
ESRI, which stands for Environmental Systems Research Institute,
is the premier computer mapping and spatial analysis company that provides the
industry standard software platform for GIS. Their website has a nice short
history of GIS. Below is a quick summary:
They begin in 1960 with the National Center for Geographic
Information and Analysis which evolved with early computers. In 1963 Roger
Tomlinson set out to develop the Canada Geographic Information System in order
to inventory Canada’s natural resources and automate data processing and storage
of that information. He also coined the term geographic information system. In
1965 the Harvard Laboratory for Computer Graphics developed software known as SYMAP.
Geographers, planners, and computer scientists collaborated there to develop
early GIS applications. In 1969, a member of that Harvard Lab, Jack Dangermond,
and his wife Laura, founded Esri to help land use planners and resource
managers. They developed software tools, formats, and work-flows, many still in
use today. Esri went commercial in 1981 with ARC/INFO, making their software
available to a wider public.
It was around the mid-1980’s is when GIS began to be used
more extensively in science applications. Geologists and cartographers mapping land
surfaces, subsurface features, and mostly human-made above surface features,
had long superimposed various “layers’ to see how they matched and how best to design
various things. Archaeologists could overlay maps of settlements from different
time periods to help discover how things changed spatially. Biologists could map
plant and animal populations. Environmental scientists could map point-sites of
pollution, how pollution disperses, and contamination plumes in groundwater and
surface water. Geologists could compare subsurface features to surface features.
Because digitized layers were not available for all spatial
data, some of us sometimes had to use a pre-computer technology: light tables,
a surface with a light underneath, so that two paper maps of the same scale could
be superimposed. One could also use ‘see-through’ tracing paper. I did this
with coal seam structure maps and coal mine maps to predict depth to set gas well
casing below the coal seam and to predict whether that seam was mined out and a
void, possibly filled with water, would be encountered. Sometimes we had
multiple coal seams and multiple mines to set multiple strings of casing
through, so we had to be careful. We also had to overlay lease maps and topographic
maps for spotting wells in suitable areas. With lease line distancing
requirements this could be challenging. Often, I would spot wells for
development plays, then the surveyor would go to the location and see if that
was feasible. Sometimes he would call and suggest alternate locations based on
topography and forest cover.
With well-defined computer map layers in GIS programs like
ESRI’s ArcGIS or ArcView the process is a bit easier nowadays and doesn’t require
a big area to spread out maps. Spatial knowledge has come a long way in the
past 35 years and helps to streamline many applications. Global positioning satellites
set the stage for accurate location in three dimensional xyz space. With free
GPS software on our smartphones the process of knowing where you are is
simplified. When we are somewhere our coordinates can be read by others who can
see where we are on a map just like we can see where we are when we’re driving.
GIS has so many practical applications in so many fields and such accuracy that
the methods of the pre-GIS past will simply fade away.
GIS is the basic technology for mapping spatial data. It is
synonymous with mapping itself, just computerized, digitized into raster and vector
data and packaged into map layers. Superimposition and what we can learn from
that is often the goal. Interpreting spatial information is part of so many
human endeavors. Newer technologies like drones, remote sensing, robotics, automated
switching for energy production and manufacturing, and infrastructure monitoring,
rely on it. Drones can be used for things like detection of oil and gas pipeline leaks by flying them along the routes with detectors embedded.
The dashboards mapping out the spread of coronavirus are an
unfortunate but valuable new application for GIS. ESRI partners with the WHO,
the CDC, and other public health bodies to put together geographic depictions
of the data. GIS also aids the ‘contact tracing’ necessary to see where a
carrier of the virus has been, although this can get into the realm of surveillance,
more specifically AI surveillance by tracking our phone GPS history.
Integrating GPS and GIS helps police and emergency medical
personnel, natural disaster response, property assessment, mapping of
underground utilities, wires, water pipes, gas pipes, etc. The list is pretty much
endless and having accurate spatial data saves lives and makes lives easier. GIS
can help farmers water and fertilize crops with great precision and less waste.
‘Call Before You Dig’ services help contractors avoid dangers by consulting detailed
maps of underground features, which can be quite extensive in urban
environments. GIS is often a primary feature of ‘Big Data’ which can be analyzed
to find hidden trends. Political redistricting and the U.S. Census depend on
GIS. Federal, state, county, and municipal governments rely on GIS. Knowledge
often depends on databases and databases often include necessary spatial data
so GIS is a key part of many databases.
Some of us economic geologists like to stare at maps. It
helps to get our exploration mind in perspective. Our own subsurface mapping
programs have evolved in tandem with GIS and they work best with surface GIS layers
superimposed.
Esri is always improving their software and making it
compatible with other software and formats so that we can zoom in to what we
want to see or zoom out for a more global perspective. Although for many
businesses, competition is useful, for something like GIS it is rather
necessary that a single platform be standard. Esri has provided such a
standard. A single platform standard will be desirable for other things too
like switching dynamic energy buying and selling based on dynamic pricing. This
is related to the Internet of Things and GIS is a key part of that as well. Knowing
where things are on a map or within a system is geographic information and that
knowledge is essential. Esri calls it the science of where.
References:
History of GIS, Esri website, (esri.com)
Dashboards Give Geographic Perspective to Coronavirus,
in ArcNews Esri, Spring 2020, Vol.42 No. 2
ArcNews Esri, Spring 2020, Vol.42 No. 2
The
Rise and Fall of “House Gas”, Changing Royalties, and Other Well Operator vs.
Landowner Issues
I just read
a LinkedIn post where an oilfield fabricator was hooking up wells for landowners
in an abandoned Kansas coalbed methane field and it set me off on a quest for
statistics and history of well-gas hookups for landowners.
Oil
& Gas Royalties
The United
States is one of the few countries in the word that allows landowners to
collect royalties from the mineral resources extracted from their land by oil
& gas companies. Details of the mineral lease are set down in the lease
agreement. The ratio is quite generous. Typically, the royalty rate is at 1/8
or 12.5% of gross profit but in more recent prolific and competitive plays such
as the shale gas and oil plays, 20% is more common and more than 20% is quite possible.
The Canadian royalty rate is typically just a flat 10%. In other countries, the
country may own all the minerals. Royalty rates vary in European countries from
0 to 20%. Some of these rates changed as it appeared that fracking could be
viable in some European countries. One major reason fracking has been adopted
in few other countries than the U.S. and Canada is that there are few well-established
landowner royalty provisions and thus, few incentives for landowners to support
it. Some states charge much higher royalties for leases on certain lands – the state
of Texas charges a 25% royalty on some lands and other states have much higher
than the 12.5% royalty. In 2015 the Obama administration upped federal land
royalties to 18.75% on some lands. Also upped was the minimum delay rental bonus
bid to hold leases for future drilling. This went up from the previous low of
$2 per acre.
It should also be noted that the landowner may not be the lease owner. This is perhaps unfortunate but this situation of a lease "severed" from the landowner became common
in the U.S. in the early-mid 20th century when shrewd politicians collected mineral leases, keeping them separated from landowners. Whether this is the case for a property is revealed when land is bought or sold. My own 35-acre property has the minerals severed which effectively means that the lease-owner could come a drill wells on my property without my permission, although I would have some rights in siting. This situation has served to create much antagonism among landowners.
The idea of
landowners being mineral royalty owners in the U.S. began from the founding
fathers rejecting the faraway British Crown collecting taxes from the colonists.
Under President Warren G. Harding in 1920, the Mineral Leasing Act set
landowner royalties at 12.5%.
In the early
times of the shale gas and oil plays amidst high gas and oil prices and highest
percentage of landowner cuts, landowner royalties were phenomenal, allowing landowners
to strike it rich. As production grew and prices subsided those royalties also
subsided. In addition, well operators looked for ways to increase their own revenue.
Changing
Lease Requirements and Controversial “Post-Production Costs”
Oil and gas
leases in the U.S. have tended to vary in requirements. For example, some have
provisions for so-called “post-production costs,” while other don’t. Chesapeake
Energy spurred the provisions for post-production costs by making leases to
deduct them before paying landowner royalties which sparked some fierce debate
about the practice. With high natural gas prices nobody saw a need for such provisions
but as those prices dropped and profits became more constrained the well owners
looked for ways to enhance dwindling profitability. The practice has sparked
controversy. That is one reason among several that landowners in high-leasing
unconventional gas and oil areas have banded together in landowner groups to
more or less standardize their lease requirements.
With unconventional
horizontal wells the well units of a lease or multiple leases are necessarily
much larger in areal extent than vertical wells so that more acreage is
required for a single well and much more for a group of wells on a single well
pad. If the well or pad site is on one’s property, the property owner may also
receive a site fee, ranging from $2000 to $15000 per well, according to the
Penn State Extension article referenced below.
Landowner
Group Leasing
Since it
sometimes takes quite a bit of time before a lease becomes available for
drilling, the common practice is to pay landowners annual delay rental payments
before well(s) are drilled on the lease in order to hold the lease for future
drilling. If there is some production on the lease then future drilling is
already secured by that production, a situation known as “held by production”
so that rental payments are not required. What is payed to landowners for delay
rental, also called a bonus, varies according to region, play, and presumed
market value of the mineral resource.
The following
quote is from the very informative Penn State Extension article referenced
below:
“A word
about landowner groups: You might have heard friends or neighbors talk about
landowner groups in the context of gas leasing. There are different types of
landowner groups. Some exist simply for sharing information about what
companies are looking to lease in their particular area, current rates, and any
special terms or conditions to the leases. Other groups are involved in
marketing their land--they seek out and maximize acres that share a border and
make bid proposals to energy companies interested in leasing. Still other
landowner groups engage in collective bargaining, in which all landowners sign
off on leasing terms accepted by the majority. This saves energy companies many
hours of individual negotiations and gives landowners a strong negotiating
position with companies looking to lease land.”
Well
Hook-Ups for House Gas
The practice
of offering well gas hook-ups to landowners had been dropping and was being
replaced by offering them a flat fee just before the advent of unconventional
shale production. These days it is rarely offered. One reason is simply
liabilities and maintenance. Typically, the landowners were required to pay for
hook-up to the well, but hook-ups were often done by well tenders. Well tenders
that work for the well operators need to plan and do the well hook-ups and
maintain any potential problems. I remember working for a company that had variable
lease requirements and landowner well hook-up issues. Some had multiple
buildings outfitted with gas hook-ups, including multiple commercial
greenhouses. Other situations involved people illegally hooking up gas to
nearby residences, splitting off from their neighbor’s hook-ups. Leaks had to
be fixed and disruptions addressed. Since natural gas is potentially explosive,
this could be a safety issue as well.
Depending on
the comparative cost of purchasing natural gas from the local utility, free gas
for landowners can be of very significant value that may last in full for
decades. People who live in rural areas where utility natural gas hook-ups are
not available also benefit much from such free house gas.
A More
Recent Source of “House Gas”
Portable aerobic
digesters offer home and business owners another source of house gas, but one
that is magnitudes lower in volume unless one is involved in agriculture that
involves much agriculture waste, food waste, or collected manure. Inexpensive
digesters are common in some places in Asia as a means to get methane for
cooking and thus reduce the production of toxic wood and dung smoke from
cooking fires.
References:
Millions
Own Gas and Oil Under Their Land. Here’s Why Only Some Strike It Rich – by Marie
Cusick and Amy Sisk, in NPR (npr.org), March 15, 2018
Federal
Oil and Gas Royalty and Revenue Reform – by Nicole Gentile, in Center for
American Progress (americanprogress.org), June 19, 2015
An
Overview on Royalties and Similar Taxes: Oil and Gas Upstream Sector Across
Europe -by Deloitte, April 2017
Natural
Gas Exploration: A Landowner’s Guide to Leasing in Pennsylvania – by Penn State
Extension, last updated Sept. 19, 2017
