Hydrogen vs. LNG: Is H2 a realistic energy source for the future?

Last week, H2TechOnline hosted Capstone Industrial Training Solutions’ very own LNG Operations Specialist & Design SME, Mehdy Touil on their podcast series “H2-Tech Talk”. Mehdy is a globally recognized natural gas liquefaction specialist, with 20 plus years’ experience in the Oil & Gas industry, having worked on the world’s largest natural gas projects and multi-billion USD facilities across Qatar, Russia, & Algeria.


H2Tech is a sub-brand of Gulf Energy and the first technical publication devoted to applications and trends for the global hydrogen industry. On the latest installment of the series, Mehdy discussed the feasibility of hydrogen replacing natural gas as an energy source. Mehdy and H2Tech touch on liquified natural gas infrastructure being repurposed for hydrogen, liquid hydrogen shipping, and hydrogen-fueled gas turbines for power generation.


Listen to the podcast below or on the H2Tech website.
Listen to the podcast here, or read it below:

Do you think that LNG and hydrogen are in direct competition?


It depends on the kind of competition that we are talking about. In terms of emissions at the combustion point, there is no denying that LNG is a significant source of GHGs, moreover when you add methane leaks. But if you look closely at the supply chain for both fuels, the picture is much more complicated, without even considering the color spectrum or I would rather say the flavors we are using to categorize hydrogen. In terms of technological maturity and reach, LNG is king with decades of incremental development and significant investment that have positioned natural gas as the energy source needed for the transition. As per the IGU annual report, last year the global LNG trade reached an all-time high of more than 370 million tonnes versus a liquefaction capacity of 460 million tonnes, with a fleet of more than 640 vessels able to deliver LNG around the world beyond land-locked pipeline networks. On the other hand, we have most of the 130 million tonnes of hydrogen generated annually using carbon-intensive methods, like from natural gas by steam methane reforming, and categorized as grey hydrogen with almost 10 kg of CO2 emitted for 1 kg of grey hydrogen. A key point to consider here, and in contrast to LNG, is that hydrogen is consumed most of the time at its point of production in refineries or ammonia plants. So, I would say that no, LNG, and hydrogen are not in direct competition.


But what about low-carbon, green H2 options?


We must be cautious about a particular narrative being pushed for the adoption of green hydrogen as the fuel of the future, which is what the hydrogen economy, or the hydrogen hype I would say is all about. As a technical person, I see hydrogen as an energy carrier rather than an energy source, unfortunately the dominant narrative is quite the opposite. Hydrogen is not an efficient, and indeed not a cheap energy carrier. In most cases, I find it hard to justify using expensive electricity generated from renewable sources of energy to produce hydrogen by electrolysis in a very inefficient, uneconomical way. Of course, electrolyzers are becoming cheaper and more efficient but that’s not the point because the greenest energy is the energy we don’t consume. We will also need to develop a dedicated supply infrastructure, which is almost inexistant now. There won’t be enough green electricity to produce green hydrogen to displace fossil fuels, which is the path investors and politicians are pushing for. Producing all of today’s hydrogen output from electricity would require 3 600 TWh, more than the total annual power generation of the European Union. In parallel, we are talking about a planned 10,000 GW by 2050 with significant losses along the way, which does not even cover a fraction of the hydrogen produced today. And don’t get me started on the pressure requirements for storing h2, which require a considerable amount of energy and investment. I believe there are more opportunities to reduce carbon emissions using renewable electricity, which is the goal, than wasting it on green hydrogen as a fuel. I have seen peer-reviewed studies about using hydrogen for heating homes published last week in the UK and they all came down to the same conclusion: more expensive than natural gas, less efficient and definitely not safe for residential use. Is this where we want to spend green, intermittent electricity?


Would you favor blue hydrogen instead?


Let’s be honest here. Some of my peers in the natural gas and LNG industry, including decision-makers, think that green hydrogen is an existential threat and blue hydrogen, along with its Carbon Capture and Storage promises, has been marketed as our savior. However, gas prices are at an all-time high. If we want to talk about large-scale energy storage with blue hydrogen as a medium, I haven’t yet seen affordable, scalable CCS solutions for blue hydrogen that could compete with green hydrogen in terms of pricing. In terms of volumes, the obvious answer is yes but in terms of emissions and price, certainly not. I would prefer focusing on LNG and increase capacity beyond 2030 to meet the increasing demand while we continue developing energy storage solutions to accelerate electrification. There is a reason why global demand for coal has kept rising, even before the conflict in Ukraine.


Do you believe that LNG infrastructure can be repurposed for hydrogen?


This is not a realistic vision, more of a convenient political wish supported by lobbying groups. We have very limited resources to solve the issue of decarbonization, I don’t think injecting hydrogen in gas pipelines and burning the mix at the end is an area we should invest in. As per the IEA, building up low-carbon hydrogen production capacity will account for more than a quarter of cumulative global investment by 2050, a quarter, that’s a lot. It’s probably great news for the hydrogen industry or if you’re an electrolyzer manufacturer, but not so much for the environment from an efficiency point of view where every percent of energy saved counts. The idea that we can swap equipment and repurpose existing gas distribution networks to hydrogen has gained massive support worldwide, especially in Europe where government subsidies are the main drive behind the concept. The Hydrogen Science Coalition and Paul Martin have done a fantastic job at explaining why this is a bad idea: the work required to compress, and transport Hydrogen is 3 times more than the compression work required for natural gas. Think about the size, or the number of compressors that would be required and the gas turbines needed to drive them. We have also pressure drops to account for, the “line pack” phenomenon and hydrogen embrittlement issues with carbon-steel pipes. Even with a lower hydrogen content, we would still face significant inefficiencies and increased leaks. Yet, all we hear is how easy and green the conversion would be from natural gas to hydrogen. And politicians are happily taking the bait. It’s sounds great to say that hydrogen is a zero-emission energy carrier, but that’s not a fact.


What is the prospect for LH2 shipping in your opinion?


I remember well the media frenzy about the first shipment from Japan to Australia last January. Liquifying hydrogen at -253degree C is energy-intensive and expensive, moreover when you must worry about boil-off, which is far worse than that of LNG. If we continue the comparison with LNG, a standard LNG carrier with a capacity of 160 thousand m3 would carry around 73 thousand tons of liquified natural gas, whereas Kawasaki is proposing a new design with the same 160 thousand m3 capacity to carry 11,200 tons of liquid H2. Again 73 thousand tonnes of LNG vs 11 thousand tons of Liquid H2. I am not talking about the difference in energy density, but you can still imagine the enormous logistical challenges in terms of shipping, and the CAPEX of developing, deploying this new design while considering the BOG losses for long voyages. I am talking of course about insulation, loading arms and a whole new infrastructure. Look at what happened to NASA’s Artemis hydrogen-powered rocket last month, and those guys have a solid experience working with liquid hydrogen. Also, I am also not sure there are cryogenic pumps on the market today able to handle 160 thousand m3 of hydrogen at -253 in a reasonable time. And back to shipping, some studies have suggested other methods like using ammonia or methanol to carry hydrogen but factoring the conversion and reconversion cost and energy losses would have a decisive impact on the final delivery price versus fossil fuels, at least for now. I also don’t expect to see a global trade for liquid H2 that would replicate LNG market and shipping routes. It would be best to utilize hydrogen at the production point for industrial uses and fertilizers production. Remember, except for few places like India, most ammonia plants are located near affordable sources of natural gas. Not because it is convenient but because it is cheaper.


Your thoughts on hydrogen-fueled gas turbines for power generation?


Most gas turbines are fuel-flexible machines to some extent, and manufacturers have already started to include hydrogen-ready products in their portfolios or are offering retrofits for existing machines. First, gas turbines consume dozens of tons of fuel per hour, again I don’t see any economic rationale for burning expensive electrolytic hydrogen, even when blended with natural gas, to generate electricity. If it is for the sake of reducing emissions, use direct electricity instead and cut the losses. From a technical perspective, beyond a 30% hydrogen blend, there are serious challenges to consider. Hydrogen burns rapidly and its flame speed can lead to flash backs and catastrophic pressure oscillations can happen. There is also a delicate balance that needs to be maintained if you want to keep NOx emissions within limits while avoiding flash backs at the same time. There are problems with flame detection inside the combustion chamber, sealing issues and complex fuel system controls that increase safety risks. Of course, for every technical problem there is a technical solution, and there are several gas turbines running successfully on various blends of H2 now with efficiencies like regular gas turbines. Yet, studies have shown that hydrogen-fueled gas turbines are competitive only in energy systems that impose a stringent cap on CO2 emissions, with assumptions made beyond 2040 for low-cost electrolyzers.


Closing thoughts?


I am not against hydrogen, and I am certainly not against electrolysis. But I am extremely skeptical on the prospect of hydrogen replacing natural gas. I think the best thing we can do with hydrogen is to focus on decarbonizing the current production, itself a monumental task. I am not denying that human activities are disrupting weather patterns, but selling hydrogen hope using alarmism is a counter-productive approach. There is no perfect solution and I believe that divesting from fossil fuels now and stopping funding new projects will lead to catastrophic results not only in terms of emissions but energy security imperatives as well. We obviously need to support innovation in new technologies and improve existing ones, but we also need economical solutions, otherwise it won’t work, and we will end up wasting precious time. We have seen the global resurgence of coal because of high gas prices, and I don’t expect any improvement in the mid-term. However, the world will continue to rely on natural gas and LNG for the foreseeable future.