SC 10-24-19 Written Communications October 15, 2019
Steven Scharf, Mayor SUBMITTED VIA EMAIL
City of Cupertino
Attn: Cupertino City Council
10300 Torre Avenue
Cupertino, CA 95014
sscharf@cupertino.org
RE: City of Cupertino Development of Reach Codes
Dear Mayor Steven Scharf:
Thank you for the opportunity to comment on the City of Cupertino’s proposed Reach Codes aimed at reducing
greenhouse gas emissions in the building sector. The Western Propane Gas Association (WPGA) seeks to be a
valuable contributor in both the development of these codes and the policies and procedures that may emerge as
a result of these discussions.
While we applaud efforts for building decarbonization, WPGA believes that Reach Codes disincentivizing
propane as a complementary fuel source to electric are fundamentally misguided. WPGA hopes that regulators
will look to the example that the City of San Luis Obispo is setting with the development of their Reach Codes
and recognize the value that propane provides on a number of levels.
Propane provides affordable, clean energy for low income communities as well as a vital back-up power for
solar powered homes when battery power is low. Disincentivizing propane as a complementary power to solar
has an unintended consequence to make solar homes more expensive and less reliable when power generation is
not at peak levels.
Furthermore, there has been numerous discussions throughout California regarding planned power outages and
safety black-outs. In a recent article published by Politico (PG&E begins massive power shut-off in California to
avoid wildfires) it is noted that the Public Safety Power Shutoff could affect 2.4 million electricity users.
Propane delivers energy resiliency for communities facing safety black-outs which can be critical for those
powering life-sustaining equipment. Vulnerable citizens such as people on dialysis or simply the many
individuals using electric powered wheelchairs can use propane energy for reliable power.
When looking towards the future, our industry is investing in renewable propane, derived from sustainable
sources like beef tallow or vegetable oil. We hope that regulators take a more holistic view of the
complementary role propane plays alongside decarbonization efforts including solar, wind and other renewable
fuels.
The Western Propane Gas Association appreciates your work in this area and looks forward to working with you
as the City of Cupertino and the State strive to reduce greenhouse gas emissions through comprehensive clean
energy solutions.
Sincerely,
Ben Granholm
Regulatory Affairs Specialist
cc: Andre Duurvoot, Sustainability Manager
From:Scott Shell
To:City of Cupertino Sustainability Commission
Subject:electrification reach code
Date:Tuesday, October 22, 2019 9:43:09 AM
Dear members of the Cupertino Sustainability Commission,
I am unable to make your meeting on 10/24, but would like to encourage you to recommend an electric
reach code that requires electric heating and hot water as your peer cities are doing. These appliances are
~90% of residential gas use, and are the most expensive and difficult to retrofit later.
Exceptions can be allowed for cooking if desired, and if a stove is pre-wired, no retrofit is required—just
replace the appliance.
I also encourage you to apply the ordinance to ALL buildings (with exceptions for specific building types if
required).
San Francisco reports that 97% of their new residential units have been in high rise residential, so these
projects need to be included as well as commercial.
Thank you for all your work on this key issue.
Scott
Scott Shell FAIA, LEED® AP BD+C, CPHC®
Principal
Pier 1 The Embarcadero, Bay 2
San Francisco, CA 94111
+1 415-214-7277
From:Rand, Stephanie on behalf of Kenney, Robert
To:City of Cupertino Sustainability Commission
Cc:Berman, Janice; Cline, Darin; Brooks, Anna; Cunningham, Kelly; Kenney, Robert; Andre Duurvoort; Albert
Salvador, P.E., C.B.O; aimee.bailey@svcleanenergy.org
Subject:All-Electric New Construction Support
Date:Tuesday, October 22, 2019 3:10:05 PM
Attachments:All-Electric New Construction Support Letter RKenney 2019 Cupertino.docx.pdfDear Sustainability Commission, Attached please find my letter regarding PG&E’s All-Electric New Construction Supportfor the City of Cupertino. Sincerely,
Robert
Robert S. Kenney
Vice President
State and Regulatory Affairs
Pacific Gas and Electric Company
P. O. Box 77000
Mail Code B23A
San Francisco, CA 94177-00001
Robert.Kenney@pge.com
(415) 973-2500 (office)
Robert S. Kenney
Vice President
State and Regulatory Affairs
P. O. Box 77000
San Francisco, CA 94177-00001
Mail Code B23A
(415) 973-2500
Robert.Kenney@pge.com
October 22, 2019
VIA EMAIL TO: sustainabilitycommission@cupertino.org
Sustainability Commission
City Hall
City of Cupertino
10300 Torre Avenue
Cupertino, CA 95014
Dear Sustainability Commission:
Pacific Gas and Electric Company (PG&E) is proud to provide electric and natural gas service to the
City of Cupertino. And we are committed to helping customers and the community achieve their
energy goals. As part of this commitment, PG&E welcomes the opportunity to support the City of
Cupertino’s efforts to promote efficient, all-electric new construction, when it is cost-effective.
PG&E strongly supports California’s climate and clean air goals. We recognize that achieving these
goals requires a range of approaches and tools, including increasing the use of energy-efficient electric
appliances in buildings when cost-effective. PG&E welcomes the opportunity to avoid investments in
new gas assets that might later prove underutilized as local governments and the state work together to
realize long-term decarbonization objectives. With all this in mind, PG&E supports local government
policies that promote all-electric new construction when cost effective.
Beyond new construction, PG&E believes a multi-faceted approach is needed to cost-effectively
achieve California’s broader economy-wide long-term GHG reduction objectives, including both
electrification and decarbonizing the gas system with renewable natural gas and hydrogen. As
California’s decarbonization policies evolve, PG&E will continue to ensure the safe and reliable
operation of the electric and gas systems to continue supporting the customers that depend on us.
PG&E appreciates the partnership with the City of Cupertino during its policy development process,
which allows us to prepare for the future and continue providing the best service possible to
customers. PG&E continuously forecasts load in its service territory and implements upgrades to the
distribution grid to meet the demand. PG&E fully expects to meet the needs that all-electric buildings
will require. PG&E remains ready to engage with our customers, local government, businesses, and
community members to meet their needs safely, reliably, affordably, and with clean energy.
PG&E looks forward to continuing to work with the City of Cupertino to accomplish its policy goals.
October 22, 2019 Page 2 of 2
Thank you, and have a safe day.
Sincerely,
Robert S. Kenney
Vice President
cc: Andre Duurvoort, Sustainability Manager [AndreD@cupertino.org]
Albert Salvador, Building Official [AlbertS@cupertino.org]
Aimee Bailey, Ph.D., Director of Decarbonization and Grid Innovation,
Silicon Valley Clean Energy [aimee.bailey@svcleanenergy.org]
Anna Brooks, Sr. Manager, Public Affairs, PG&E [anna.brooks@pge.com]
Darin Cline, Sr. Manager, Government Relations, PG&E [Darin.Cline@pge.com]
From:BRUCE KARNEY
To:Andre Duurvoort; Gilee Corral
Cc:; Anna Weber; Vignesh Swaminathan; Meera Ramanathan; Angela Chen
Subject:Fwd: Natural Gas Cooking as a Social Justice Issue
Date:Wednesday, October 23, 2019 9:37:03 AM
For your consideration in developing the Cupertino Reach Code...
Cheers,
Bruce Karney
---------- Original Message ----------
From: BRUCE KARNEY <>
Date: October 23, 2019 at 8:54 AM
Subject: Natural Gas Cooking as a Social Justice Issue
At last night's Mtn. View Council Meeting I heard a new argument for
banning natural gas kitchen appliances in single family homes. I thought it
was a rather compelling notion that other advocates might want to share
with their City Councils. Credit for this idea goes to Vice Mayor Margaret
Abe-Koga.
Her perspective is that if a reach code requires all-electric kitchens in new
multi-family homes, but not in new single family homes, then it essentially
is giving a "license to pollute" to only those who are wealthy enough to buy
a new single family home. It gives an option to the owners of new single
family that renters and condo-residents do not have. This, it is a form of
discrimination based on wealth.
Rather than addressing this disparity by allowing natural gas kitchens in
multi-family residences, the Vice Mayor recommended eliminating the
natural gas option in new single family homes. The rest of the Council
agreed, and her modification to the staff proposal was adopted on a
unanimous vote. Starting in 2020, new residences in Mountain View,
whether single-family or multi-family, will have all-electric kitchens.
Cheers,
Bruce Karney
Chair, Carbon Free Mountain View
From:Rod Sinks
To:BRUCE KARNEY
Cc:Andre Duurvoort; Gilee Corral; Gary Latshaw; Anna Weber; Vignesh Swaminathan; Meera Ramanathan; Angela
Chen
Subject:Re: Natural Gas Cooking as a Social Justice Issue
Date:Wednesday, October 23, 2019 10:42:44 AM
Yes, I watched the meeting and have asked for a written summary of Mountain View council's
actions. They also mandated electricity in commercial kitchens, with a waiver process to allow
exceptions for preparing cuisine when there is no electric option (like Menlo Park).
I think it would be useful for the Sustainability Commission and the Council to understand
what actions Mountain View, Menlo Park and San Jose have taken.
Rod
On Wed, Oct 23, 2019 at 9:37 AM BRUCE KARNEY <> wrote:
For your consideration in developing the Cupertino Reach Code...
Cheers,
Bruce Karney
---------- Original Message ----------
From: BRUCE KARNEY <>
Date: October 23, 2019 at 8:54 AM
Subject: Natural Gas Cooking as a Social Justice Issue
At last night's Mtn. View Council Meeting I heard a new argument for
banning natural gas kitchen appliances in single family homes. I thought
it was a rather compelling notion that other advocates might want to
share with their City Councils. Credit for this idea goes to Vice Mayor
Margaret Abe-Koga.
Her perspective is that if a reach code requires all-electric kitchens in
new multi-family homes, but not in new single family homes, then it
essentially is giving a "license to pollute" to only those who are wealthy
enough to buy a new single family home. It gives an option to the
owners of new single family that renters and condo-residents do not
have. This, it is a form of discrimination based on wealth.
Rather than addressing this disparity by allowing natural gas kitchens in
multi-family residences, the Vice Mayor recommended eliminating the
natural gas option in new single family homes. The rest of the Council
agreed, and her modification to the staff proposal was adopted on a
unanimous vote. Starting in 2020, new residences in Mountain View,
whether single-family or multi-family, will have all-electric kitchens.
Cheers,
Bruce Karney
Chair, Carbon Free Mountain View
Personal Comments of Sustainability Commissioner Gary Latshaw, Ph.D.
Fellow Commissioners and Cupertino Environmental Staff
Cc: Ro Khanna, Tom Pyke, and Rod Sinks
In view of the recent publication of the IPCC – Special Report Oceans and Cryosphere, along
with other scientifically reviewed publications, I feel that the proposed Reach Codes (Staff’s
October 24th Report) are inadequate to meet the needs of reducing carbon emissions.
Building codes are designed, in part, to consider low probability, but potentially ruinous events
can be avoided. Historically the codes have addressed such issues as: structural integrity,
earthquake resilience, water & air safety, cost effectiveness, and other factors that are
important for the long-term utility of the structure. In recent years the State of Cali fornia has
recognized the necessity of moving society to zero-net greenhouse gas emission society and
has mandated the codes address this need.
The Reach Codes are designed to meet that goal of reducing greenhouse gases. However, given
the recent scientific reports they do not provide for a rapid enough transition. In fact, upon
reviewing the Staff Report, I feel the Environmental Commission needs to reexamine the
climate goals that drive the Climate Action Plan.
I am suggesting the following for the re ach code:
1. All Electric Construction – No natural gas
a. Several Cities have already done this (Berkeley and Menlo Park) while several
others are in the process of doing so (Mt. View, San Jose).
b. Removal of natural gas is essential to allow the complete disma ntling of the
natural gas infrastructure, which includes of 3 million miles of pipelines.
c. Apply the ban for all types of buildings unless a compelling need can be
established.
d. Recent publications point to the serious degradation to internal air quality 1
caused by natural gas cookstove cooking.
2. EV adoption – Required to eliminate the use of Fossil-Fuel Vehicles
a. All new construction of single-family dwellings should have 240 outlets capable
of supporting level 2 charging.
b. All multi-family dwellings should have 240 outlets available for every parking
space or two parking spaces can share one 240 outlet.
The following pages summarize recent information on the risk that climate change
phenomenon might become much worse in a short period of time due to continued emissions
of greenhouse gases.
1 Building Decarbonization Presentation by Panama Bartholomy, https://www.youtube.com/watch?v=dRkz_FPi6z8
Personal Comments of Sustainability Commissioner Gary Latshaw, Ph.D.
Due to climate change, which has resulted from atmospheric heating from anthropogenically
introduced greenhouse gases, some of the major atmospheric and ocean flows are being
altered. The most recent IPCC Special Report Oceans and Cryosphere, states succinctly1:
The polar regions are losing ice, and their oceans are changing rapidly. The consequences of this
polar transition extend to the whole planet and are affecting people in multiple ways2.
I will briefly review these changes. The driving force of wind patterns in the Northern
hemisphere comes from the difference in the temperatures of the Arctic relative to the
equator. This difference causes air flows from the equator to flow northward to the Arctic. As
these flows interact with the rotation of the earth, they form the polar vortex of high-speed
winds in the upper atmosphere. This vortex is largely believed to provide substantial stability
and provides predictable seasonal patterns. The farmers in turn depend on these patterns to
select crops, growing times, harvesting times, etc.
One aspect of climate change has been to warm the Arctic faster than the equator 1. This
then reduces the temperature difference between the equator and the Arctic, which then
reduces the speed of the air flows and, most likely, weakens the Polar Vortex. The weakened
Vortex allows very cold Arctic air to flow down to midlatitudes. In recent years this has caused
exceptional winters in our Northwest and very cold snaps in nominally warm places like Italy.
Also, it has allowed warm air from midlatitudes to flow to the Arctic and produce exceptionally
warm weather in the Arctic (see Figure 2 and Appendix B).
The Arctic ice acts like a refrigerator door keeping methyl hydrates, which lie on the
ocean floor, and massive organic matter frozen (often beneath glacial ice} inactive. A significant
warm spell in the Arctic will lead to release of greenhouse gases from both these sources.
Modest releases have already been noted. But the fear is that a confluence of a warming world,
and an exceptional storm in the Arctic could lead to an ice-free period that would allow a
massive release of greenhouse gases (see Figure 1).
For this reason, the IPCC Special Report Ocean and Cryosphere states3:
It is very likely that Arctic sea ice extent continues to decline in all months of the year; the strongest
reductions in September (-12.8 ± 2.3% per decade; 1979-2018) are likely unprecedented in at least
1000 years. It is virtually certain that Arctic sea ice has thinned, concurrent with a shift to younger ice:
since 1979, the areal proportion of thick ice at least 5 years old has declined by approximately 90%. It is
very likely that approximately half the observed sea ice loss is attributable to increased atmospheric
greenhouse gas concentrations. Changes in Arctic sea ice have potential to influence midlatitude
weather on timescales of weeks to months (medium confidence). {3.2.1.1; Box 3.2}
See Figure 3 for a graph of the declining Arctic ice.
2 IPCC Final Draft, Special Report Ocean and Cryosphere, September 2018, Chapter 3, page 3 -3
3 IPCC Final Draft, Special Report Ocean and Cryosphere, September 2018, Chapter 3, page 3 -4
Personal Comments of Sustainability Commissioner Gary Latshaw, Ph.D.
In his recent book, A Farewell to Ice: A Report from the Arctic, Peter Wadhams4 investigates the
potential damage of a possible loss of Arctic ice. He examines a release of 50 gigatons of Greenhouse
Gases in Carbon dioxide equivalents. Here is part of what he concludes:
The extra temperature rise due to the methane by 2040 is 0.6oC, a substantial extra contribution. This
would be catastrophic for mankind, partly because it is so quick…
Measured at present value the cost of this increase comes out as 60 trillion dollars over century….5
Two figures follow demonstrating some of the concepts discussed previously.
Appendix A is a copy of a recent Washington Post article about the diminishing ice.
Appendix B is a summary of some of the negative effects of natural gas usage.
4 Peter Wadhams is the former Director of the Scott Polar Institute in Cambridge. He has made more than 50
expeditions to both polar regions, working from ice camps, icebreakers, aircraft and uniquely, submarines. He has
several awards and is a Fellow of the Royal Geographical Society and a Member of the Finnish Academy.
5 Wadhams, Peter, A Farewell to Ice: A Report from the Arctic, Oxford Press, 2017, page 125 and 126
Personal Comments of Sustainability Commissioner Gary Latshaw, Ph.D.
Figure 1: This figure describes where highly potent climate gas – methane – is in “cold” – storage in the
Arctic. Much of it is in frozen methyl hydrate on the continental shelf. Some free gas is trapped at lower
depths. The permafrost, which covers much of northern Siberia, Alaska, and Canada, has prevented the
tons of frozen vegetation from decaying. In the decay process, microbes emit both methane and carbon
dioxide.
From A Farwell to Ice:
The amount of methane stored in the hydrate deposits in the entire ocea n bed is estimated to be more
than thirteen times the amount of carbon in the atmosphere and amounts to 10,400 Gt .6
6 Wadhams, Peter, A Farewell to Ice: A Report from the Arctic, 2017, page122
Personal Comments of Sustainability Commissioner Gary Latshaw, Ph.D.
Figure 2 – Slides provided by the Climate Reality Project
Top image is a depiction of the jet stream when it diverted from its normal confines to the North Pole
and split into two streams. This provided an avenue for warm air to visit the North Pole causing
unprecedented high temperatures that threaten the stability of the Arctic ice.
Personal Comments of Sustainability Commissioner Gary Latshaw, Ph.D.
Figure 3: Screen shot from Polar Ice Science Center (http://psc.apl.uw.edu/research/projects/arctic-sea-
ice-volume-anomaly/) in October of 2019.
The above graph shows the decline in Arctic Sea Ice extent over the past 29 years. If the downward
trend continues, then we are likely to see an ice-free September within the next decade. This could lead
to increases in the release of methane, which is a highly potent greenhouse gas.
Personal Comments of Sustainability Commissioner Gary Latshaw, Ph.D.
Appendix A
The Washington Post
North Pole surges above freezing in the dead
of winter, stunning scientists
By Sason Sameno
w
Personal Comments of Sustainability Commissioner Gary Latshaw, Ph.D.
Feb. 26, 2018 at 10:52 a.m. PST
The sun won’t rise at the North Pole until March 20, and it’s normally close to the coldest time
of year, but an extraordinary and possibly historic thaw swelled over the tip of the planet this
weekend. Analyses show that the temperature warmed to the melt ing point as an enormous storm
pumped an intense pulse of heat through the Greenland Sea.
Temperatures may have soared as high as 35 degrees Fahrenheit (2 degrees Celsius) at the pole,
according to the U.S. Global Forecast System model. While there are no direct measurements of
temperature there, Zack Labe, a climate scientist working on his PhD at the University of
California at Irvine, confirmed that several independent analyses showed “it was very close to
freezing,” which is more than 50 degrees (30 degrees Celsius) above normal.
The warm intrusion penetrated right through the heart of the Central Arctic, Labe said. The
temperature averaged for the entire region north of 80 degrees latitude spiked to its highest level
ever recorded in February. The average temperature was more than 36 degrees (20 degrees
Celsius) above normal. “No other warm intrusions were very close to this,” Labe said in an
interview, describing a data set maintained by the Danish Meteorological Institute that dates back
to 1958. “I was taken by surprise how expansive this warm intrusion was.”
Personal Comments of Sustainability Commissioner Gary Latshaw, Ph.D.
Such extreme warm intrusions in the Arctic, once rare, are becoming more routine, research has
shown. A study published last July found that since 1980, these events are becoming more
frequent, longer-lasting and more intense.
“Previously this was not co mmon,” said lead author of the study Robert Graham, from the
Norwegian Polar Institute, in an email. “It happened in four years between 1980-2010, but has
now occurred in four out of the last five winters.”
Graham explained that these warming events are related to the decline of winter sea ice in the
Arctic, noting that January’s ice extent was the lowest on record. “As the sea ice is melting and
thinning, it is becoming more vulnerable to these winter storms,” he explained. “The thinner ice
drifts more quickly and can break up into smaller pieces. The strong winds from the south can
push the ice further north into the Central Arctic, exposing the open water and releasing heat to
the atmosphere from the ocean.”
Personal Comments of Sustainability Commissioner Gary Latshaw, Ph.D.
Scientists were shocked in recent days to discover open water north of Greenland, an area
normally covered by old, very thick ice. “This has me more worried than the warm temps in the
Arctic right now,” tweeted Mike MacFerrin, an ice sheet specialist at the University of Colorado.
Such warm water is appearing to have an effect on air temperatures. At the north tip of
Greenland, about 400 miles to the south of the North Pole, the weather station Cape Morris Jesup
has logged a record-crushing 61 hours above freezing so far this calendar year. The previous
record, dating to 1980, was 16 hours through the end of April in 2011, according to Robert
Rohde, a physicist at Berkeley Earth, a nonprofit that conducts temperature analysis. At one
point, the temperature was as high as 43 degrees (6.1 degrees Celsius).
Kent Moore, a professor of atmospheric physics at the University of Toronto, who published a
study in 2016 linking the loss of sea ice to these warm events in the Arctic, said a number of
factors may have contributed to the latest warming episode.
For one, he said, recent storms have tracked more toward the North Pole through the Greenland
Sea, drawing heat directly north from lower latitudes, rather than through a more circuitous route
Personal Comments of Sustainability Commissioner Gary Latshaw, Ph.D.
over the Barents Sea. He also said ocean temperatures in the Greenland Sea are warmer than
normal. “The warmth we’re seeing in the Greenland Sea is definitely enhancing the warm events
we’re seeing,” Moore said. “I’m surprised how warm it is, but I am not sure why.”
The rise in Arctic temperatures is probably also tied to a sudden warming of the stratosphere, the
atmospheric layer about 30,000 feet high — above where most weather happens — that occurred
several weeks ago, Moore said. Why these stratospheric warming events happen is poorly
understood, as are their consequences. However, they tend to rearrange warm and cold air
masses, and this latest one has also been linked not only to the Arctic warmth but also to the
“Beast from the East” cold spell over Europe.
Moore stopped short of saying that the warm spikes observed in the Arctic in recent years are a
sure sign that they are becoming a fixture of the winter Arctic climate; more data is needed, he
cautioned.
Whether a blip or indicative of a new normal, scientists have uniformly expressed disbelief at the
current Arctic temperatures and the state of the sea ice.
“This is a crazy winter,” said Alek Petty, a climate scientist at NASA, in an interview. “I don’t
think we’re sensationalizing it.” “It’s never been this extreme,” Ruth Mottram, a climate scientist
at the Danish Meteorological Institute, told Reuters.
Personal Comments of Sustainability Commissioner Gary Latshaw, Ph.D.
Appendix B – Harmful effects of Methane – the primary component of natural gas
The above picture shows the massive natural gas release that occurred at Portal Ranch in
Southern California in 2015. The release poisoned the air causing evacuation in the region.
Natural gas is primarily methane – CH4. Methane is a very potent greenhouse gas. It is 100
times more potent a warming chemical than CO2. CH4 decays in the atmosphere and br eaks
down into CO2 and water vapor. There are many business and government interests in
promoting natural gas as a “bridge fuel”. Because combustion of natural gas produces about
twice the heat as coal combustion for the same amount of CO2 emissions, it is often promoted
as a superior fuel to coal. However, because there is substantial leakage of CH4 into the
atmosphere in the acquisition, storage, and transportation, the continued use of natural gas
poses a substantial climate risk.
There are powerful commercial and political proponents of this dangerous fuel. Qatar recently
announced that they were going to process natural gas. According to the Guardian 7 Jim Hansen
(see Appendix H) has written to the Government of UK, “’If the UK were to join the US by
developing gas fields at this point in time it will lock in the methane problem for decades,’
he wrote, adding that fracking would fatally undermine the UK’s attempt to fulfil its climate
obligations.’” At a recent symposium at Stanford University Douglas K immelman8 spoke
7 October 13, 2018, “Top climate scientist blast UK’s fracking plans as ‘aping Trump’
8 October 29, 2018 “Douglas Kimmelman: Inconvenient Truths about Energy (Energy Seminar), video link available:
https://energy.stanford.edu/events/energy-seminar-douglas-kimmelman-inconvenient-truths-about-energy
Personal Comments of Sustainability Commissioner Gary Latshaw, Ph.D.
about his plans as founder of Energy Capital Partners to promote natural gas in the United
States. He foresees great financial gain in liquefying it and shipping all over the world.
I fear that any policy that enables the expansion of na tural gas is deeply flawed.
The following graph is from the 5th IPCC Assessment. In the graph you can see the
significant contribution to radiative forcing that methane is causing – it is 16% of the total
warming from greenhouse gases. It is only second to CO2. However, if mankind can
substantially reduce its emissions of methane, then its contribution to climate forcing will
diminish relatively quickly.
There is not a solid consensus within the scientific community about what fraction of
methane does escape, and what timeframe should be used to determine its global warming
potential. However, there are many climate scientists who believe natural gas power may
be comparable to coal power because of this leakage.
This is from the Union of Concerned Scientists (my underlining):9
Whether natural gas has lower life cycle greenhouse gas emissions than coal and oil depends on
the assumed leakage rate, the global warming potential of methane over different time frames,
the energy conversion efficiency, and other factors [5]. One recent study found that methane
losses must be kept below 3.2 percent for natural gas power plants to have lower life cycle
emissions than new coal plants over short time frames of 20 years or fewer [6]. And if burning
natural gas in vehicles is to deliver even marginal benefits, methan e losses must be kept below 1
percent and 1.6 percent compared with diesel fuel and gasoline, respectively. Technologies are
available to reduce much of the leaking methane, but deploying such technology would require
new policies and investments [7].
9 December 18, 2018 https://www.ucsusa.org/clean-energy/coal-and-other-fossil-fuels/environmental-impacts-of-
natural-gas#.XBmI3KeZPKY
Personal Comments of Sustainability Commissioner Gary Latshaw, Ph.D.
Measurements of natural gas emissions over the entire operation in the US are estimated to be
2.4% of production10. However, this figure comes from a disparate set of measurements – some
of which resulted in 9% leakage. On top of everything, the Trump administration has eliminated
many of the restrictions that the previous administration placed on the petroleum industry.
Since the future is impossible to predict, the most certain constraint is to directly restrict the
use of fossil fuel energy.
10 Methane leaks erode green credentials of natural gas , by Jeff Tollefson, Nature, Vol. 493, 3 January 2013