October 2021, Vol. 248, No. 10
Features
Future-Proofing US Pipelines with Hydrogen
By Nicholas Newman, Contributing Editor
The construction of additional natural gas, crude oil and fuel pipeline across North America is being challenged by environmental and climate action measures by the public as well as politicians.
The cancellation of the long-delayed Keystone XL oil pipeline is a case in point. Likewise, NextEra Energy Inc. is writing off a $1.2 billion investment in the Mountain Valley gas pipeline from West Virginia to Virginia thanks to various regulatory and legal delays, and it will not be the last.
Fossil fuel pipeline owners and operators are vulnerable to this change in public and government sentiment toward their industry. Therefore, they are searching for ways to avoid the prospect of their assets becoming stranded as government and state measures to reduce carbon emissions come into effect, the most visible being a ban on new combustion engine vehicles as soon as 2035 in California, New Jersey and Massachusetts.
The current and most popular solution going forward is to convert existing pipeline networks and to build any new ones to transport low-carbon hydrogen.
This is not a wholly new strategy because there are already approximately 1,600 miles (2,600 km) of hydrogen pipelines in operation in the United States, reported by the Office of Energy Efficiency and Renewable Energy (EERE). However, these pipelines are owned and operated by a different set of companies, serving a quite different set of customers.
Most North American hydrogen pipelines are owned by merchant hydrogen producers, such as Air Liquide, Air Products and Chemicals, Hydrogenics, Messer Group, and The Linde Group. Today, most such hydrogen pipelines are located where large hydrogen users are, such as petroleum refineries and chemical plants along the Gulf Coast region.
Potential Market
The dash toward hydrogen is not surprising given its environmentally friendly credentials compared to fossil fuels. Indeed, according to a recent National Renewable Energy Laboratory (NREL) report, US demand for hydrogen could increase from the current 22 million mt/year to 41 million mt/year by 2050.
The necessary decarbonization of energy-intensive industrial processes would account for about half of the growth in demand for hydrogen as detailed in an IHS Markit November 2020 report, which broke industry hydrogen demand into several segments: synthetic hydrocarbon production (14 million mt/year), metals refining (12 million mt/year), oil refining (7 million mt/year), ammonia production (4 million mt/year) and biofuels production (9 million mt/year).
As electric vehicle production overtakes and dominates the combustion engine, fuel cells could account for about a quarter of hydrogen consumption at some 29 million mt/year. The remainder could support other energy systems, such as seasonal electricity storage (15 million mt/year), and the rest could be used as injection into the natural gas system.
Storage, Distribution
The current European ambition to introduce hydrogen into existing natural gas pipelines for an energy mix of some 20% hydrogen and 80% gas could be adopted in the U.S.
Already, New Orleans-based utility Entergy Group, with 30,000 MW of electric generating capacity to serve the needs of its 2.9 million utility customers in Arkansas, Louisiana, Mississippi and Texas, has shown an interest in hydrogen alongside Mitsubishi Power, National Grid and Sempra Energy.
In the Rocky Mountains, a consortium of Mitsubishi Power, the state-owned Intermountain Power Agency and the Los Angeles Department of Water and Power is looking into developing an underground storage cavern where green hydrogen would be produced and stored. The Utah project, known as the Advanced Clean Energy Storage Project, will pair more than 1,000 MW of hydrogen electrolyzers with giant salt caverns that could each store more than 150 GWh of dispatchable energy capacity, equivalent to more than 150 hours of electricity.
The New England power and gas utility National Grid in New York state and Sempra Energy in California is looking at hydrogen in distribution natural gas pipelines. If given the go-ahead, they will blend hydrogen with natural gas in their deliveries to industrial, commercial and residential customers in the coming decade.
National Grid, in partnership with Standard Hydrogen Corp., is planning to showcase a multi-use, renewable, hydrogen-based energy storage and delivery system in New York by the end of 2022. This venture with Standard Hydrogen Corp. will focus on developing what National Grid called the first hydrogen storage and delivery system in New York’s Capital Region. This is a green project that will produce hydrogen exclusively from purchased renewable power, store it and market it as a zero-carbon energy to support electric services, heating, zero-emissions vehicles and commercial gas services.
National Grid distribution pipelines could also help decarbonize industrial processes dependent on natural gas and even heating. National Grid has said that the adoption of hydrogen will help toward achieving its goal of reducing its greenhouse gas emissions from direct operations and its electricity and gas businesses by 80 percent and 20 percent, respectively, by 2030.
Sempra Energy’s subsidiary San Diego Gas & Electric Co. (SDG&E) and Southern California Gas Co. (SoCalGas) have been pioneers in developing the storage, transmission and use of hydrogen in California.
In 2013, SDG&E and the National Renewable Energy Laboratory (NREL) started working together to operate the first U.S.’s utility-owned community microgrid in Borrego Springs, California.
This microgrid comprises a 26-MW solar plant, two battery storage systems, two generators and an ultra-capacitor to provide consistent power to the remote desert town of Borrego Springs during emergencies and planned outages on the larger grid.
In 2017, SoCalGas and NREL created the nation’s first carbon-free, power-to-gas pilot system. The technology takes excess electricity and converts it to hydrogen, which can be used, stored or combined with carbon dioxide and fed to a bioreactor to produce renewable natural gas.
Now, in 2021, Sempra Energy is working on developing decarbonization of regional and industrial hubs, or industrial clusters, to mitigate carbon emissions from industrial processes – such as manufacturing, steel, and chemicals – that cannot be electrified.
Types of Hydrogen
Hydrogen is versatile and available in a variety of formats such as gas, liquid and paste. It is also colorless, odorless and tasteless, but it is also a flammable, gaseous substance. Hydrogen is classified by color – gray which dominates production, or blue or green to denote the power used in making it.
Gray hydrogen accounts for more than 90% of all hydrogen currently produced. It is made by extracting hydrogen from natural gas by the steam reforming process. But this process emits about 9.3 kg of greenhouse gases per kilogram of hydrogen produced; therefore, it is not particularly environmentally friendly. However, it is the lowest cost method of producing hydrogen today with natural gas prices being so low.
Blue hydrogen is more environmentally friendly than the gray and is produced in the same way as the gray. However, the greenhouse gas emissions from production are captured and either stored or repurposed.
Green hydrogen, as its name suggests, is environmentally friendly and has zero emissions because it is produced with either nuclear power or renewable energy from hydropower, wind power or solar power. Green hydrogen is expensive – currently at between $3/kg and $6.55/kg – compared to gray hydrogen – below $2 per kilogram, owing to its small-scale production by electrolysis of water.
Unlike natural gas, hydrogen can be burned without emitting carbon dioxide into the air. Run it through a fuel cell to generate electricity and the only waste is water; produce hydrogen using electrolyzers powered by solar plants or wind farms and it becomes a way to store massive amounts of renewable energy – far more than any of today’s batteries can hold.
The best part for pipeline companies: delivering hydrogen, where it needs to be in bulk, could require the same basic infrastructure that now carries natural gas.
The Problem
For gas suppliers, the question is if the pipeline network is ready to deliver hydrogen to customers. Certainly, much of the existing cast iron and steel gas pipeline transmission grid could pose a possible problem as hydrogen can cause embrittlement of metal pipelines.
Currently, National Grid is conducting research into the impact of various blends of hydrogen could have on its networks, starting at 2%, rising to 20% and eventually to 100%.
U.S. gas pipeline owners and operators own approximately 3 million miles (5 million km) of pipelines. If these US owners and operators could gain the support for hydrogen from investors, regulators and the public, they can capitalize on their assets for the foreseeable future and make the country green.
If given the go-ahead, they [National Grid and Sempra Energy] will blend hydrogen with natural gas in their deliveries to industrial, commercial and residential customers in the coming decade.
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