Pre-Test Results for June 2023 LH2 Era™ Webinar Session 3: Zero Boil-Off Case Study

Question 1:

Some of the methods to eliminate venting losses due to boil-off gas (BOG) in liquid hydrogen systems are briefly mentioned here: https://blog.matthewemoran.com/search?q=myth+busting. This is also an example of the last option for me... needing to vent about the persistent myths regarding hydrogen.

Question 2:

Everyone agreed on the last option not being part of systems engineering. Unfortunately some version of that argument is often made when a new project starts. The cost and time impact of the decision often comes back to haunt the project for the remainder of its life. For an example approach to avoid this trap, see: https://blog.matthewemoran.com/2020/08/on-august-24th-i-was-on-forum-360-panel.html

Question 3:

This topic is discussed in detail here: https://blog.matthewemoran.com/2023/04/hydrogen-myth-busting-episode-3.html

Question 4:

When hydrogen gas is liquefied by bubbling it up through a container of liquid hydrogen, there is no system energy input associated with liquefaction for that isolated process. A lifecycle analysis is required to find the total liquefaction energy for the system based on its lifecycle operations. This would include the liquefaction input energy for the initial LH2 quantity plus any make-up LH2 added over the system lifetime.

The lifecycle analysis should also take into account any cold sink functions that the LH2 enables such as: cooling of various process streams; reduction of environmental heat leak; temperature difference driven power cycles; refrigeration cycles; etc. The resulting lifetime effective energy cost of liquefaction will be higher than zero but less than 20% for many systems.

This is why quoting "energy loss" due to liquefaction as a single value is a misleading figure of merit. In properly designed LH2 operational systems, a significant amount of this "lost" energy is utilized for other functions.

Question 5:

Everyone got this answer right! Unfortunately, most reports and studies still bake in the assumptions of distributed production, storage, and distribution when it comes to hydrogen. This is a remnant of the fossil fuel paradigm that doesn't apply to hydrogen systems that do all of those functions in one place. More on this topic here: https://blog.matthewemoran.com/2023/04/hydrogen-myth-busting-episode-3.html

The ability to produce prodigious quantities of potable water from hydrogen usage is also a significant and unique benefit that is often ignored. Same with the ability to have an isolated renewables microgrid operating anywhere on the globe using hydrogen storage. Additional comments about these aspects can be found here: https://blog.matthewemoran.com/2022/05/energy-shapeshifting-with-hydrogen.html

Question 6:

The answer to this question is 1 W/m^2. More details can be found in Section 3.2 of the Cryogenic Fluid Management report available online here: https://sites.google.com/view/matthewemoran/training#h.ir8xm9d8wn6h

This is a handy value to remember for doing quick assessments of heat load into an LH2 vacuum jacketed dewar (or an LH2 tank in space) with an inch of MLI applied. Equations for the surface area of common tank shapes can be found in Section 3.3 of the same report cited above.

Question 7:

There has been a great deal of inaccurate media coverage about hydrogen being a potential so-called "indirect" greenhouse gas (GHG). This reporting has grossly misrepresented the contents of some recent studies that are based on a series of unproven hypotheses that would require a good deal of research (and funding) to address.

Whether or not scientific investigation of this topic is a good use of research funds is debatable. The one known fact on this topic is that hydrogen is not a GHG. And there are no evidence-based facts to support that it will become an "indirect" GHG of any consequence. More of my thoughts on this can be found here: https://blog.matthewemoran.com/2022/05/hydrogen-myth-busting-episode-2.html

Matt Moran is the Managing Member at Moran Innovation LLC, and previous Managing Partner at Isotherm Energy. He's been developing power and propulsion systems for more than 40 years; and break-through liquid, slush, and gaseous hydrogen systems since the mid-1980s. Matt was also the Sector Manager for Energy & Materials in his last position at NASA where he worked for 31 years. He's been a co-founder in seven technology startups; and provided R&D and engineering support to many organizations. Matt has three patents and more than 50 publications including the Cryogenic Fluid Management series. He also leads the monthly LH2 Era™ Webinar.

ThinkTech Hawaii Interview: Hydrogen Myths vs Facts

Moving Beyond Hydrogen Fairytales and Zombie Myths

On the topic of hydrogen, there is a great deal of misinformation being circulated. Liquid hydrogen systems in particular are sometimes characterized as being a far-off vision that will require many years to deploy. The truth is there are no true technology gaps preventing the widespread application of hydrogen systems. The answer to many questions about hydrogen can be summed up as "it has already been done".

Unfortunately, inaccuracies have even made their way into key reports from authoritative government and international sources. These publications frequently contain errors and omissions, especially on the topic of liquid hydrogen. It is critically important to resolve this issue since public policy, regulations, funding priorities, and private sector investments are heavily influenced by these types of publications.

In this interview, common myths about hydrogen are dispelled with facts on the topics of safety, readiness level, leaks, materials, green hydrogen, energy storage, and system losses. And the 20-20 Vision for the Countdown to Hydrogen™ mnemonic will help with remembering some key hydrogen facts.

Matt Moran is the Managing Member at Moran Innovation LLC, and previous Managing Partner at Isotherm Energy. He's been developing power and propulsion systems for more than 40 years; and break-through liquid, slush, and gaseous hydrogen systems since the mid-1980s. Matt was also the Sector Manager for Energy & Materials in his last position at NASA where he worked for 31 years. He's been a co-founder in seven technology startups; and provided R&D and engineering support to many organizations. Matt has three patents and more than 50 publications including the Cryogenic Fluid Management series. He also leads the monthly LH2 Era™ Webinar.

Upcoming LH2 Workshops, Courses, Interviews, and Webinars

There are a number of upcoming liquid hydrogen (LH2) events I'll be involved in over the next several months. Here is a rundown for those who may be interested in watching or participating.

ThinkTech Hawaii Interview: Hydrogen Myths vs Facts

Mitch Ewan, Hydrogen Program Manager at the Hawaii Natural Energy Institute (HNEI), will be interviewing me for this online broadcast. Common myths about hydrogen will be dispelled with facts on the topics of safety, readiness level, leaks, materials, green hydrogen, energy storage, and system losses. The livestream will be on May 25, 2023 at 4pm - 5pm HST at: https://thinktechhawaii.com/.

For those who aren't able to watch the broadcast live, the video is available here: https://youtu.be/vBWHhycEaIY. This is my second interview with Mitch and ThinkTech Hawaii. A recording of the first interview from 2019 can be found here: https://blog.matthewemoran.com/2019/06/thinktech-hawaii-interviews-matt-moran.html

Cryogenic Engineering Conference

This conference is being held July 9-13, 2023 in Honolulu, Hawaii, USA. I may be chairing a session, but mostly going to hear about the latest cryogenic advancements and connect with colleagues. Historically, some of the published papers from this annual conference become seminal references in the field. The conference website is here: https://www.cec-icmc.org/2023/

A description of the conference: "The Cryogenic Engineering Conference (CEC) focuses on the science and engineering required for cryogenic applications. Examples of topics in past conferences include liquefied gases for fuels, space applications of cryogenic liquids, cooling and performance of superconducting magnet systems in medical, transportation, power, and basic research applications, as well as the systems, machinery, control technology and thermodynamics required to produce low temperatures."

Energy & Mobility Conference & Expo

This conference is being held Sep 12-15, 2023 in Cleveland, Ohio, USA. I'm teaching a full day workshop on liquid hydrogen systems at this event with my colleague Wesley Johnson of NASA. Information and registration for the workshop can be found here: https://www.energyandmobility.org/schedule/workshops/liquid-hydrogen-lh2-systems/

A description of the conference: "...a multi-industry international conference focused on energy and modern mobility, with an emphasis on advanced technologies, the challenges of systems integration, autonomy, and related product value chains and business models. All are critical factors enabling the transition to a robust, decentralized and resilient energy sector, the security of our critical infrastructure, and the evolution of mobility via advanced controls and alternative fuels, including Hydrogen, towards energy-efficient, cost-effective and sustainable solutions."

Flying HY ("The World's Largest Hydrogen Aviation Event")

This event is being held October 10-11, 2023 in Grand Forks, North Dakota, USA. I'll be teaching a half day hydrogen aviation course along with Danielle McLean, Founder & CEO of HYSKY. More information can be found here: https://www.hysky.org/news-events

Danielle and I are also tentatively planning to teach a full day version of the course at the Transformative Vertical Flight meeting February 6–8, 2024 in Santa Clara, California, USA. More details will be coming later this year. The meeting website is: https://vtol.org/tvf2024

LH2 Era™ Monthly Webinar Series

This online global webinar series focused on liquid hydrogen systems (and broadcast on the first Thursday of every month) continues with a zero boil-off case study session on June 1, 2023. The following month's session on July 6, 2023 will address the topic of liquid hydrogen integrated into grid, microgrid, and other multi-function architectures and system of systems applications.

The guest speakers for these next two sessions will be Norbert Palenstijn of Leybold USA Inc; and Dr. Ngalula Sandrine Mubenga, Assistant Professor at the University of Toledo, and Founder & President of STEM DRC Initiative. More information and free registration for this webinar series can be found at: https://sites.google.com/view/matthewemoran/training

• 

  Matt Moran is the Managing Member at Moran Innovation LLC, and previous Managing Partner at Isotherm Energy. He's been developing power and propulsion systems for more than 40 years; and break-through liquid, slush, and gaseous hydrogen systems since the mid-1980s. Matt was also the Sector Manager for Energy & Materials in his last position at NASA where he worked for 31 years. He's been a co-founder in seven technology startups; and provided R&D and engineering support to many organizations. Matt has three patents and more than 50 publications including the Cryogenic Fluid Management series. He also leads the monthly LH2 Era™ Webinar.

Pre-Test Results for May 2023 LH2 Era™ Webinar Session 2: Hydrogen Evolution

Image credit: NASA

Question 1:

The primary goal of the LH2 Era™ monthly webinar series is to provide accurate and actionable information to ensure robust, high performance, and operationally safe liquid hydrogen systems: https://sites.google.com/view/matthewemoran/training#h.cse56tn4ffmk

Meeting that goal requires assessing your current awareness about hydrogen systems and then leveling up by participating in the webinar. Take this poll to see where you are in an adapted version of the Gartner hype cycle: 1. Initial Exposure, 2. Inflated Expectations, 3. Disillusionment or Misinformation, 4. Pragmatic Productivity

Here's an interesting graphic of the hype cycle: https://en.wikipedia.org/wiki/Gartner_hype_cycle#/media/File:Hype-Cycle-General.png

Not necessarily followed by all technologies (or even most), and not generally applicable to hydrogen since it's been around a very long time. Interesting to compare though...

Question 2: 

The first three myths are addressed here: https://blog.matthewemoran.com/2022/04/hydrogen-myth-busting-episode-1.html

I can neither confirm nor deny the unicorn answer, but there seems to be a consensus on glitter and rainbows on the internet. And that's how the first three myths probably got started too...

Question 3: 

300 series stainless steel is the most common structural material used for all types of hydrogen service. However, note that 400 series stainless steel has a ductile to brittle transition temperature (DBTT) above liquid hydrogen temperature so is generally not suitable for cryogenic service in this range.

Aluminum alloys are historically the second most common structural material for hydrogen service. Some very recent research papers are suggesting there may be some hydrogen embrittlement possible at very high pressures. I've never witnessed nor heard of this issue in any operational system, but something to stay up to date on as more data becomes available.

Teflon can be used as a seal material or gasket for liquid hydrogen service since it still cold flows at these temperatures. Other seal material options are also appropriate depending on the application.

Cotton canvas infused with highly flammable chemicals was used for hydrogen containment in an infamous dirigible more than 85 years ago. This is an inappropriate material choice for any lifting gas (hydrogen, helium, hot air, etc.) since an electric discharge can set the entire structure aflame: https://blog.matthewemoran.com/2022/04/hydrogen-myth-busting-episode-1.html

Question 4: 

The answer to this one is over a decade as of the time I visited UT Austin several years ago. This of course speaks to the myth about hydrogen leaking though everything. Methods and materials to mitigate hydrogen leaks are very well established and have been operationally validated with liquid hydrogen systems in continuous use since the 1960s.

The first answer is not relevant but nonetheless also true. I did a bar (pub) crawl with my oldest son years ago when he lived there during the city's annual SXSW festival. We gave up before reaching the last stop but had a great time :)

Question 5: 

I've been driving my battery electric vehicle (BEV) for 18 months sitting on top of a lithium-ion battery pack with this quantity of energy storage. But if live rounds were being fired at it (or the battery compartment was damaged in a collision) I'd abandon it and get far away as quickly as possible. Li-ion batteries are subject to thermal runaway if any of the cells are crushed or penetrated, resulting in that energy being rapidly released and leaving behind a smoldering melted mass.

For the fossil fuel options, there are at least three serious hazards in this scenario: 1. ignition (conflagration or detonation); 2. inhalation of toxic fumes or smoke; 3. asphyxiation. The liquid fuels also spread quickly along the ground if the containment is breached, significantly increasing the physical area of risk exposure. Propane is heavier than air so it increases the physical volume of risk exposure. Natural gas is lighter than air so will eventually dissipate unless confined. Both gases pose a significant detonation hazard in this scenario.

In the case of compressed gaseous hydrogen, this scenario has already been tested on composite overwrap (COPV) pressure vessels (without the bystander). From the conclusion section of the test report: "When penetrated by AP [armor piercing] rounds, the cylinder will vent quickly without producing a flame. The cylinder will not catastrophically fail when pierced by a round, retaining its structural integrity and venting its contents safely."

The full report can be accessed here: http://www.powersourcesconference.com/Power%20Sources%202018%20Digest/docs/P10-6.pdf

Also note that hydrogen is not toxic, and is actually used as a breathing gas with oxygen (hydrox) for very deep diving. At ambient temperature in air, it rises at a rate of 20 m/s. And it produces no smoke nor soot when it burns.

Liquid hydrogen (LH2) was not tested in the cited report. LH2 in this scenario would vaporize very quickly if the containment vessel is breached and begin rising as it quickly warms up. Liquefied natural gas (LNG) would behave similarly, but would vaporize and rise much more slowly than LH2.

Question 6: 

Section 3.3 of the passive Cryogenic Fluid Management report provides a detailed comparison of these options. See: https://sites.google.com/view/matthewemoran/training#h.p_0kmGtNXJhZlO

The most common insulation historically for vacuum-jacketed dewar tanks is perlite powder. It has been used in many over-the-road truck trailer vessels and stationary vessels including the large LH2 spherical dewar tank built in the 1960s that supported the Apollo and space shuttle programs. It is comparatively inexpensive and has moderate thermal performance in a hard vacuum in comparison to the other options. However, perlite has a tendency to settle over time and uncover the upper portions of the vacuum space thereby increasing the heat load.

Glass microspheres have slightly better thermal performance than perlite and are not as prone to settling. They are also relatively inexpensive and were used on the new spherical LH2 dewar tank that is 50% larger than the previous tank used for space shuttle launches. 

Aerogel beads or blankets do not perform as well as perlite or glass microspheres in a hard vacuum jacket, but are better performing than those options at soft vacuum or atmospheric pressure. Aerogel insulation is more costly but may be a suitable choice for situations where thermal performance is needed in varying atmospheric and vacuum environments (e.g., a tank that is launched in normal atmosphere and then is in the vacuum of space for some period of time).

Multilayer insulation (MLI) is the best performing option in a hard vacuum jacket. It is comprised of reflective thermal shields separated by low conductivity high porosity spacer materials (e.g., double aluminized mylar with dacron net spacers). The thermal performance of MLI is affected by a number of parameters including appropriate installation and close-outs. It is the most expensive of the options shown, and is used in high performance vacuum-jacketed stationary storage tanks and various types of tanks in spacecraft applications.

Spray on foam (SOFI) provides moderate thermal performance in a normal atmosphere but has very poor performance in vacuum conditions. It is among the most inexpensive options and has been used on launch vehicle tanks and the space shuttle external tank. SOFI is not generally appropriate for stationary LH2 tanks but can be a suitable option for higher temperature cryogens depending on the use case (e.g., methane, oxygen, nitrogen, etc.).

• 

  Matt Moran is the Managing Member at Moran Innovation LLC, and previous Managing Partner at Isotherm Energy. He's been developing power and propulsion systems for more than 40 years; and break-through liquid, slush, and gaseous hydrogen systems since the mid-1980s. Matt was also the Sector Manager for Energy & Materials in his last position at NASA where he worked for 31 years. He's been a co-founder in seven technology startups; and provided R&D and engineering support to many organizations. Matt has three patents and more than 50 publications including the Cryogenic Fluid Management series. He also leads the monthly LH2 Era™ Webinar.