Hydrogen: what GWP and climate impacts?

This data-file aggregates technical data into the Global Warming Potential (GWP) of hydrogen, in order to draw conclusions for decision-makers in the energy transition. So what is hydrogen GWP versus methane?

(1) Hydrogen is not a direct GWP, as H-H bonds in the hydrogen molecule do not directly absorb infrared radiation, indeed nor do other symmetrical diatomic molecules like N2 or O2 (no permanent dipole moments).

(2) But hydrogen is an indirect GWP, as it breaks down in the atmosphere over 1-2 years, and its reaction products increase the GWP impacts of other GHGs, such as methane, tropospheric ozone and stratospheric water vapor.

(3) The best estimates we have tabulated in our data-file give a 100-year GWP for hydrogen that is 11x stronger than CO2 and for methane that is 34x stronger than CO2 (please download the data-file for the details).

(4) Concerns? In other words, if you are worried about the climate impacts of leaking 0.6 – 3.5% methane across global gas value chains, the climate impacts are effectively the same for leaking 2 – 10% hydrogen across a hydrogen value chain.

(5) 3x higher hydrogen leakage rates are not an unjustified concern, because the radius of an H2 molecule is about 3x smaller than the radius of a CH4 molecule, and the boiling point is -253C (versus -162C for methane) resulting in more boil-off, and thus upper estimates for H2 leakage rates as high as 20% have crossed our screen.

(6) The hydrogen industry might adapt: by monitoring and mitigating its leakage rates, much like the gas industry needs to do; and by preferring shorter and simpler value chains, direct substitution for pre-existing hydrogen in industry; or transporting hydrogen in carrier molecules (toluene, ammonia, electrofuels are less likely to result in hydrogen emissions, even if they are more expensive).

(7) CH4 Condemnation? Over 50% of the GWP impacts of hydrogen arise because hydrogen mops up hydroxyl radicals, which in turn, prevents these hydroxyl radicals from breaking down methane molecules. Thus the 100-year warming impacts of methane are exacerbated. In other words, the climate impacts of atmospheric hydrogen directly link to the atmospheric impacts of methane. The more worried you are about one, then logically, the more worried you should be about the other. Hydrogen and methane are “in it together” when it comes to GWP.

(8) CH4 Collaboration. Atmospheric methane is around 1,900 ppb, 160% above pre-industrial levels. Every year, about 40% of the world’s methane emissions comes from natural sources like wetlands, 25% from agriculture, cow burps and rice, 25% from coal, oil and gas and c10% from waste landfills. H2’s GWP can be improved by encouraging better methane management in all of these other categories.

Recent Commentary: please see our article here.

Biogas: the economics?

Biogas screens as a relatively expensive source of energy. Our project model requires $20/mcfe gas, a $50/ton CO2 price and a $50/ton tipping fee, in order to make a 10% unlevered return on a $430/Tpa plant.

The economics are most sensitive to tipping fees, which are often imposed by regulators, to incentivize biogas projects at more competitive gas and power prices: an expensive tax on consumers, but a kingmaker for biogas projects. Without tipping fees, it would require c$1,500/ton CO2 prices before biogas was cost-competitive.

The aim of our model is to simplify the economics of an anaerobic digestion plant, producing biogas from food and agricultural waste that would otherwise have ended up in landfill. Assumptions can be flexed in rows 5-35. Explanatory notes around costs and economics are provided in the ‘Notes’ tab.

Methane emissions from pneumatic devices, by operator, by basin

Methane leaks from 1M pneumatic devices across the US onshore oil and gas industry comprise 50% of all US upstream methane leaks and 15% of all upstream CO2. This data-file aggregates data on 500,000 pneumatic devices, from 300 acreage positions, of 200 onshore producers in 9 US basins.

The data are broken down acreage position by position, from high-bleed pneumatic devices, releasing an average of 4.1T of methane/device/year to pnuematic pumps and intermediate devices, releasing 1.4T, through to low-bleed pneumatic devices releasing 160kg/device/year.

It allows us to rank operators. Companies are identified, with a pressing priority to replace medium and high bleed devices. Other companies are identified with best-in-class use of pneumatics (chart below). The download contains 2018 and 2019 data, so you can compare YoY progress by company.

A summary of our conclusions is also written out in the second tab of the data-file.  For opportunities to resolve these leaks and replace pneumatic devices, please see our recent note on Mitigating Methane.

Fugitive methane: what components are leaking?

This data-file looks through 35 different technical papers and data-sources to tabulate the methane leaks from different components around the oil and gas industry.

The largest leaks per event are from losses of well control, which can emit 10-1M tons per annum. Next are mid- and downstrseam facilities at 1-10kTpa.

The largest leaks by upstream component are compressor seals (1-100Tpa) and millons of pneumatic devices (0.01-10Tpa), which each comprise c20-30% of total upstream leaks.

Potentially overlooked categories include wellheads, storage tanks and workover practices. All are quantified in the data-file. The theme is addressed in detail in our note, mitigating methane.

Methane Leaks from Downstream Gas Distribution

This data-file tabulates the methane emissions from downstream gas distribution across 160 US gas networks, which cover 1.1M miles of mains, 61M metered customers and >90% of the country’s retail gas demand.

Downstream US methane leakages average 0.2% by volume, explaining 5.7kg/boe of emissions. Two thirds of these leaks can be attributed to gas mains. Leakages are correlated with the share of sales to smaller customers. And state-owned utilities appear to have 2x higher leakage rates the public companies.

US gas utilities’ performance is screened to assess c80 distinct companies, including: Altagas, Atmos, Centerpoint, CMS, Dominion, DTE, Duke, Edison, National Grid, PG&E, Sempra, Southern Co, Spire, UGI, WEC & Xcel.

Mitigating methane: what methods?

This data-file screens the methods available to monitor for methane emissions. Notes and metrics are tabulated for Method 21, Optical Gas Imaging, fixed sensors, ground labs, aircrafts, drones and satellites; including advances at the cutting edge of each method.

Emerging screening methods, such as drones and trucks are also scored, based on results from an excellent recent technical trial. The best drones can detect almost all methane leaks >90% faster than traditional methods.

Companies developing next-generation methane-mitigation technologies are screened, including 11 public  companies and 33 private companies. This peer group filed 150 patents in 2018-19. 8 companies seem particularly exciting to us.

Operators are also screened, across the dozen largest Energy Majors, to estimate their methane leaks and broader methane intensity across the supply chain.

Methane emissions detract from natural gas?

This short model calculates the impact of methane emissions on the CO2/boe of burning natural gas, compared against coal. With methane emissions fully controlled, burning gas is c60% lower-CO2 than burning coal.

However, taking natural gas to cause 120x more warming than CO2 over an immediate timeframe, the crossover (where coal emissions and gas emissions are equivalent) is 4% methane intensity. i.e., if 4-20% of methane is leaked, then the total warming from burning natural gas is equivalent to coal’s.

Permian CO2 Emissions by Producer

This data-file tabulates Permian CO2 intensity based on regulatory disclosures from 20 of the leading producers to the EPA in 2018. Hence we can  calculate the basin’s upstream emissions, in tons and in kg/boe.

The data are fully disaggregated by company, across the 20 largest Permian E&Ps, Majors and independents; and across 18 different categories, such as combustion, flaring, venting, pneumatics, storage tanks and methane leaks.

A positive is that CO2 intensity is -52% correlated with operator production volumes, which suggests CO2 intensity can be reduced over time, as the industry grows and consolidates into the hands of larger companies.

Copyright: Thunder Said Energy, 2022.