More California gas stations can provide H2 than previously thought, study says

More California gas stations can provide H2 than previously thought
A recent report by Sandia National Laboratories asks whether hydrogen fuel can be accepted at any of the 70 California gas stations involved in the study, based on a new hydrogen technologies code. Here, Sandia’s Daniel Dedrick visits a station in Oakland, Calif.  Credit: Dino Vournas

A study by researchers at Sandia National Laboratories concludes that a number of existing gas stations in California can safely store and dispense hydrogen, suggesting a broader network of hydrogen fueling stations may be within reach.

The report examined 70 commercial gasoline stations in the state of California and sought to determine which, if any, could integrate fuel, based on the National Fire Protection Association (NFPA) hydrogen technologies code published in 2011.

The study determined that 14 of the 70 gas stations involved in the study could readily accept and that 17 more possibly could accept hydrogen with property expansions. Under previous NFPA code requirements from 2005, none of the existing gasoline stations could readily accept hydrogen.

The current code, known as NFPA 2, provides fundamental safeguards for the generation, installation, storage, piping, use and handling of hydrogen in compressed gas or cryogenic (low temperature) liquid form.

This work is aligned with Hydrogen Fueling Infrastructure Research and Station Technology (H2FIRST), a new project established by the Department of Energy's Office of Energy Efficiency and Renewable Energy.

Science, risk-informed analysis can accelerate H2 station deployment

The development of meaningful, science-based fire codes and determinations such as those found in the report will help accelerate the deployment of hydrogen systems, said Daniel Dedrick, hydrogen program manager at Sandia. "This work shows that we can reduce uncertainty and avoid overly conservative restrictions to commercial hydrogen fuel installations by focusing on scientific, risk-informed approaches.

"It turns out that the number of able to carry hydrogen can be quantified," Dedrick added. "We now know that we can build more hydrogen fueling stations if we examine the safety issues within a sound, technical framework that focuses on the real behaviors of hydrogen."

Sandia's hydrogen safety, codes and standards program is a diverse portfolio of activities funded by the Department of Energy's Fuel Cell Technologies Office to provide the technical basis for developing and revising safety codes and standards for hydrogen infrastructure, including the NFPA 2 code.

The study focuses on California, which has more hydrogen-fueling stations than any other state. A key factor in the codes that Sandia examined was the separation distances required for fueling infrastructure, including fuel dispensers, air intakes and tanks and storage equipment. The code defines required distances between such components and public streets, parking, on-site convenience stores and perimeter lines around the site.

All fueling facilities are susceptible to fire due to the presence of flammable liquids and gases, said Dedrick. According to the NFPA, more than 5,000 fires and explosions a year occurred at conventional gasoline stations from 2004-2008. "Whether you are filling your car with gasoline, compressed natural gas or hydrogen fuel, the fueling facility first of all must be designed and operated with safety in mind," he said.

"If you have a hydrogen leak at a fueling station, for example, and in the event that the hydrogen ignites, we need to understand how that flame is going to behave in order to maintain and control it within a typical fueling station," explained Chris San Marchi, manager of Sandia's hydrogen and metallurgy science group. A scientific understanding of how such flames and other potential hazards behave is necessary to properly determine and mitigate safety risks, he said.

"We're comfortable with the risks of natural gas in our homes and under our streets," San Marchi pointed out. "We want to be just as confident of the safety of hydrogen in our fuel tanks and on our street corners."

Sandia researchers at the Combustion Research Facility for years have studied and modeled the intricate workings of the combustion engine and, more recently, hydrogen behavior and its effects on materials and engine components, San Marchi said. The knowledge gained by Sandia's work on the physical behavior of hydrogen and risks associated with hydrogen fuels provided the scientific basis to revise the separation distances in the NFPA 2 code for hydrogen installations.

H2 fueling stations can be as safe as or safer than gasoline stations

Under the previous code, virtually no stations could be sited at existing stations. The reason, said San Marchi, is simple: Those codes were developed via an "expert opinion-based process" and not the risk-informed process developed by Sandia researchers and now used in the code. The previous code was developed for flammable gases in an industrial setting, which carries different risks compared to hydrogen fuel at a fueling station.

"The distances set forth in the code, therefore, were much larger than we now know they need to be," San Marchi said. The risk metric used to develop the new NFPA code, he added, was that the stations accepting hydrogen fuel needed to be proven as safe as or safer than gasoline-only stations.

Some gas stations still may not be able to accept hydrogen under the new code because gas station lot sizes vary greatly, and many smaller sites – particularly those in dense, urban areas – cannot be properly configured, he said.

"Certain smaller gas stations, especially those in cities, have unusual shapes that aren't going to accommodate the right separation distances," San Marchi said. For example, he said, the required distance between a high-pressure tank carrying hydrogen and the property boundary would be too great for a "skinny" station or a wedge-shaped lot. While larger lots naturally work better in the current environment, San Marchi said, there are opportunities to develop risk mitigations that could allow even wider deployment of hydrogen fueling stations.

Enhancing performance-based parts of hydrogen code

One of Sandia's next objectives is to work with all parties to look closer at the underutilized performance-based parts of the NFPA 2 code, rather than the prescriptive-based elements that focus on rigid distance requirements.

"While the prescriptive sections of the code are typically implemented, there are also sections of the code that allow for the use of more risk analysis to optimize the fueling facility," San Marchi said. If developers and others take a more performance-based approach, he said, more existing fueling facilities will be able to integrate hydrogen systems and support the developing fuel-cell electric vehicle market.

Sandia is also in the process of developing a risk-informed approach for shortening the separation distances for storage at fueling stations, as current efforts only examined separation distances for gaseous hydrogen. Liquid hydrogen is attractive because it takes up less space than gaseous hydrogen and allows fueling stations to accommodate larger numbers of fuel-cell electric vehicles. However, there are additional issues associated with the low temperatures required for liquid systems installed on small properties.

"We need to do more experimental and modeling work to understand and evaluate the science and physics of liquid hydrogen," said San Marchi. "By evaluating the risks quantitatively, we believe we can shorten the separation distances required in the code for liquid hydrogen just as we did with . That could then lead to even more fueling stations that can accept hydrogen and support the continued growth of the fuel-cell electric vehicle market."


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NREL, Sandia team to improve hydrogen fueling infrastructure

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Jul 08, 2014
Just more useless green "science" here. How about trying to figure out how to produce, store, transport and use H2 as a fuel at a reasonable cost before trying to figure out where to site the fueling stations. Fuel cell powered cars would never exist if any reasonable long term cost assessment were performed.

Jul 08, 2014
Just more useless green "science" here. How about trying to figure out how to produce, store, transport and use H2 as a fuel at a reasonable cost before trying to figure out where to site the fueling stations.

So what's your point? You're accusing people who do research in area X of not doing research in area Y? That's pretty hypocritical.

It takes all manner of things t make an energy infrastructure work. they are looking at one of the aspects. Nothing more, nothing less. You'd probably be bawling your head off about no places for filling stations if this article were about creation, storage or transport of hydrogen, right?

Stop. Just stop with your idiotic hypocrisy. It's getting annoying (and not just a little bit embarassing).


EWH
Jul 08, 2014
Hydrogen is not an energy source, it is an energy storage method, and a pretty lousy one at that. It is very difficult and bulky to store and transport. If stored as liquid, it consumes huge amounts of energy in its liquefaction, and boils off quickly and hazardously. If stored in pressure vessels, it will explode like a bomb in crashes. If stored as a hydrate it is heavy and requires high temperatures to release. It embrittles and seeps through most metals. It burns with an invisible flame. It is only economically sourced from natural gas, which is a better storage medium in every way than hydrogen. Hydrogen could be sourced from solar or nuclear, but the former is uneconomic and the latter is best done with high-temperature reactors that do not currently exist.

Hydrogen vehicles are a pure boondoggle; research into mass marketing is a waste at best, at worst these inefficient and dangerous vehicles will actually be pushed into the market.

Jul 09, 2014
Well I''ll be danged Goober, I just found a cryogenic storage system out behind the garage next to that rusted out Desoto. I reckon we're all set to start pumping hydrogen!

Jul 09, 2014
If you do not know the difference between a fuel and a source of stored energy your comments are not really of any value.

Jul 09, 2014
@MR166

"If you do not know the difference between a fuel and a source of stored energy your comments are not really of any value."

From Wiki: Fuels are any materials that store potential energy in forms that can be practicably released and used for work or as heat energy....

Fuels are contrasted with other methods of storing potential energy, such as those that directly release electrical energy (such as batteries and capacitors) or mechanical energy (such as flywheels, springs, compressed air, or water in a reservoir).

So what is the difference? Please show us that your comments have any value.

Jul 09, 2014
Stored in this case is referring to energy that has been created in the past. Most H2 is created from natural gas and as such is not a source of energy but sink of stored energy. Producing H2 via electricity produced by solar or wind does not make H2 a source of energy. The process is so wasteful that it is not considered as a viable fuel.

Jul 09, 2014
Converting natural gas to H2 for use as a fuel is a ludicrous idea since natural gas is a perfectly good fuel in it's original state. Doing this creates more pollution and wastes more energy than using NG directly. If fusion ever is able to create ultra cheap electric power then H2 and ammonia could manufactured and become viable fuels.

Jul 09, 2014
Converting natural gas to H2 for use as a fuel is a ludicrous idea since natural gas is a perfectly good fuel in it's original state. Doing this creates more pollution and wastes more energy than using NG directly. If fusion ever is able to create ultra cheap electric power then H2 and ammonia could manufactured and become viable fuels.
I just bought motor oil made from natural gas. Its amazing how ubiquitous its become.

Jul 09, 2014
I never said that it was not a fuel. I said that it was not an energy source.

Jul 10, 2014
You can drill or mine and get products from the earth that give you a net increase in the amount of energy available for use. The same applies to trees, they are also a source of energy IE since they have a positive EROI when used for heating. That MIGHT even be true for solar and wind depending on how much backup generation is needed to stabilize the grid.

H2 on the other hand always has a negative EROI when used as a fuel since it always takes more energy to produce it than it is able to return.

Jul 10, 2014
By definition something with a negative EROI cannot be a source of energy. For instance, a battery is not a source of energy. Like commercially produced H2 it is a storage device. Both have a negative EROI. Now if the output of a wind or solar farm could produce H2 and still maintain a positive EROI H2 could be considered an energy source. When you consider all of the costs associated with the distribution and use of H2 I doubt that this is possible.

The first step would be to create and store H2 on site and use it to create electric power when the farm is unable to produce power. This would help even out the power spikes and make renewable energy much more valuable. I think that this sort of system would be too costly to be of any real value.

Jul 13, 2014
EWH - If I can take a tank of hydrogen - feed it into a fuel cell - and get electricity out the back end - how is the hydrogen not a fuel source?


Because the hydrogen is the fuel. It cannot be its own source, now can it?

Eikka recently attacked off shore wind turbines - using 25% capacity factor to run the calculations. I requested support for this number - and also provided support that the actual number is closer to 50%. Of course no response.


Perhaps I didn't see your question. Don't assume malice.

http://energynumb...nd-farms

That is one case, where the life average capacity factor of off-shore windmills is very close to 40%. I can't remember the exact article, but it's highly likely that the difference wasn't significant for the argument because the problem I usually find is that news articles say a wind park has X amount of power and then tries to hide the fact that it reallly makes much much less.


Jul 13, 2014
but the same names come up over and over attacking renewables - and spreading misinformation. I have seen the above statement about hydrogen not being a fuel source so many times here. But when pushed to support it - you get silence.


Same works both ways. There are some people who argue for renewable energy using facts, and some who argue for it using misinformation. The same names come up over and over again spreading misinformation about how excellent and wonderful renewable energies are, and then people who don't know the difference accuse me of being a liar when I try to point that out.

The question and answer here in this particular case is rather logical. A fuel its not its own source. It doesn't make itself spontaneously out of nothing. Saying that hydrogen is a fuel source is like saying potatoes are a source of potatoes, which says nothing about where the potatoes come from. Obviously they don't just pop into existence arbitrarily.


Jul 13, 2014
I cannot find any source to tell me what the eroi is of hydrogen from the steam reformation of methane. Does any one have a source?


It's somewhere around 0.8 to 0.9

Older, simpler steam reforming techniques only reach up to about 70% efficiency.

Jul 13, 2014
The malice was in using an incorrect number


Incorrect, how?

There are some off-shore wind parks that get less than 25% capacity factor, and some that achieve 50%. If I remember correctly, in the case you are referring to I asked what the capacity factor for -a particular- wind park was, because it was not provided.

If none is provided, then the actual number is anyone's guess.

I provided sources that indicated that off shore capacity is now routinely close to 50%

It would be false generalization on your part to argue that any and all of them must be because that is mostly dependent on location and less on the technology.

Sorry - your logic totally escapes me - you statement makes no sense to me. If I drill a well - and collect methane - and reform that methane into hydrogen - it seems to me that hydrogen is a fuel source - that can be burned to produce energy.


No, the hole in the ground is the fuel source - that's where the fuel comes from.

Jul 13, 2014
I do understand the point about how - if the EROI of a fuel is less than one - it is not a VIABLE energy source


No, it's not an energy source at all because you don't gain any energy.

The hole in the ground is an energy and fuel source, because by extracting the methane you gain energy in the form of a fuel.

The fact that you reform it into hydrogen doesn't mean anything special. You just changed your fuel from one kind to another kind, and if you're only looking at where the hydrogen comes from, where the source of hydrogen is, then your fuel source is the refinery, but the refinery is not your energy source. The energy source is still the hole in the ground.

The fuel source is the source where you get your fuel from.

The fuel itself is not the fuel source because it does not come of itself.

The fuel can be an energy source when you gain energy from it, and not an energy source when you don't. You don't gain energy from making hydrogen, so it is not.


Jul 13, 2014
So you see, hydrogen is not a fuel source. When I fill up a hydrogen car, I don't get hydrogen out of hydrogen - I get hydrogen out of a large gas cylinder!

Even if I cared of nothing else except what's happening inside the car, I still couldn't say that hydrogen is a fuel source, because hydrogen IS the fuel, and the source, or where it comes from is the hydrogen tank.

And the energy contained by the hydrogen in the tank does not come from the hydrogen, but from the hole in the ground where you got the methane to make the hydrogen

If I only care about what happens in the car while I'm driving it, then and only then I can say "the energy source for the motor is the hydrogen in the tank", but only if I deliberately ignore everything else that exists. Like I can say that the energy source of my laptop is the battery - while knowingly ignoring that I have to recharge the battery from the power grid because it doesn't make any energy itself.

I hope this is finally clear enough.

Jul 13, 2014
Dong energy had even managed 70% on some of their projects - during winter months.


That is to say, they've managed to find a perfect spot for the windmill.

If we assume a perfect windmill on a typical location that doesn't have any sort of abnormal wind speed distribution, presumably because it's on the sea, then the difference in capacity factor is explained completely by the average wind speed at that location. I've run a simple computational model of the expected energy production.

6.25 m/s average produces 23% capacity factor
7.50 m/s average produces 34%
8.75 m/s average produces 42%
10.0 m/s average produces 49%
etc.

So it's not about the windmills, it's about where you put them.

Or, you could cheat and install a smaller generator and claim that your turbine is less powerful than it is, and then claim you're achieving near 100% capacity factor while dumping wind past the blades. That works as well.

Jul 13, 2014
One of the biggest problems with solar and wind are their intermittent nature and the inability to predict how much power will be available at any given moment. To solve this problem and keep the grid stable, gas fired turbines are running constantly as emergency backup sources. I seem to remember that these standby plants lower the overall efficiency of renewable power by about 25%.

Jul 13, 2014
Efficiency might be the wrong word to use here. The amount of fossil fuel saved is about 25% less than the output of renewable sources would seem to imply.

Jul 13, 2014
I do understand the point about how - if the EROI of a fuel is less than one - it is not a VIABLE energy source

I think this is not entirely correct as a viability of a fuel source is not characterised by EROI alone. A fuel medium that takes more to produce than it delivers can be very well viable if the place where it is used does not have any other fuel sources which are easier to come by
(e.g. it is perfectly viable to make fuels for satellites which require more energy to produce than they give off once they are in space - just because in that case weight is more important than EROI)

Simlarly it is perfectly all right to if renewable sources had atrocious efficiencies (e.g. compared to drilling for oil or going nuclear) just because they don't pose any of the risks or generate any of the subsequent (health/environmental) costs - which are not part of an EROI calculation.

Jul 13, 2014
Anti it is true that specialty fuels have other considerations than EROI but fuels for mass consumer use should have the best EROI possible. Also if the EROI for a particular renewable is too low, when it's total energy cost from cradle to grave is considered, you can be sure that it really creates more pollution problems than it solves and lowers everyone's welfare. For instance, you and I both agree that corn based ethanol falls into this category.

Jul 14, 2014
California leading the US again with innovative forward thinking.

Jul 14, 2014
The malice was in using an incorrect number


Incorrect, how?

There are some off-shore wind parks that get less than 25% capacity factor, and some that achieve 50%. If I remember correctly, in the case you are referring to I asked what the capacity factor for -a particular- wind park was, because it was not provided.

If none is provided, then the actual number is anyone's guess.

I provided sources that indicated that off shore capacity is now routinely close to 50%

It would be false generalization on your part to argue that any and all of them must be because that is mostly dependent on location and less on the technology.

Sorry - your logic totally escapes me - you statement makes no sense to me. If I drill a well - and collect methane - and reform that methane into hydrogen - it seems to me that hydrogen is a fuel source - that can be burned to produce energy.


No, the hole in the ground is the fuel source - that's where the fuel comes from.

Jul 14, 2014
Here is an article from the oil drum about the oil sands.

http://www.theoil...de/10011


Jul 14, 2014
Anti it is true that specialty fuels have other considerations than EROI but fuels for mass consumer use should have the best EROI possible.

What good is an optimal EROI if the fuel destroys your ability to live? Don't get me wrong: EROI is important for fossil fuels and nuclear. But for superabundant energy sources (like solar/wind/wave energy) to non-polluting storage solutions (like hydrogen) its importance is practically zero.

when it's total energy cost from cradle to grave is considered, you can be sure that it really creates more pollution problems than it solves

If the energy you use from cradle to grave is also of the renewable kind then it doesn't matter at all. The assumption that the cradle to grave energy will be 'dirty' energy is a fallacy.

Jul 14, 2014
"In general - if the eroi is above 1 - then I agree with your assessment that we need to look at the full cost of a fuel - and renewables win hands down."

That is not true at all. One has to include the cost of the end product into the calculation and it's effects on the economic system. Poverty kills more people every year than CO2. Any reduction in the average life span due to pollution is dwarfed by starvation and poverty.

Jul 14, 2014
Poverty kills more people every year than CO2. Any reduction in the average life span due to pollution is dwarfed by starvation and poverty
@MR166
this is a bad choice of tactics.
first off... poverty is NOT the issue, and you have a tenuous causal link, much like the anti-gun people use
You've not established the relevance of the claim and the context.

it is very possible that, in the future (should we not be able to control AGW) we can face far more deaths from AGW than poverty (if defined deaths are considered by root cause, not secondary causes)

Jul 14, 2014
If ANY renewable can be installed and be competitive in a free market I am all for it. My only agenda is to insure that the collective decisions are as cost effective as possible when all of the unbiased data is considered.

Jul 14, 2014
If you go from an average EROI of say 30 to an EROI of say 2 you will be in impoverished. Everything that you purchase will be much more expensive including heat, food and transportation due to energy scarcity. Energy is the lifeblood of civilization and more expensive energy equals less prosperity.

Jul 14, 2014
The oil sands would not be profitable at 2008 oil prices. They are a special case anyway since they are using their own local stranded energy resources to produce more energy. On the other hand, solar and wind manufacturing competes with other manufacturing for energy raising energy costs. Thus, producing electrical energy from coal which has a very high EROI costs everyone less than producing electricity from solar which has a very low EROI.

Jul 15, 2014
Lets say it takes 1000 energy units per year to keep society running. If your EROI is 10 to one you need to find 1100 units of energy every year to fill demand. If the EROI is reduced to 2 to 1 then you need to find 2000 units to fill demand. You can see how prices would skyrocket as EROI falls.

Jul 15, 2014
producing electrical energy from coal which has a very high EROI costs everyone less than producing electricity from solar which has a very low EROI.

There are things which aren't measured in dollars which contribute to cost.
- Environmental concerns (impact on food chain. Reduction of arable land due to contamination)
- Health impact (impact on respiratory diseases/cancer rates...not only from the power plant alone but also from the infrastructure needed to ferry fuels from mines/wells to these sites)
- Subsequent costs of maintaining waste disposal sites
- Safety of supply (if even part of the fuel is imported then that is a lever which can be used in economic warfare...see Ukraine)
- Safety in case of accident (worst case scenarios)
- Safety against and possible fallout from sabotage
- ...

EROI captures none of this.


Jul 15, 2014
Strange Hydro is cheaper than coal because 99% of it was installed when energy prices were 1/10 of today's prices not because EROI does not matter. But you did bring up a valid point. When considering the economic viability of renewables, it should be based on the projected costs of the fuels that they replace over the life of the project and not just today's costs. The importance of today's EROI can be diminished by energy inflation.

That being said, if well being is proportional to access to energy which I suspect it is, energy inflation is not a positive but a drag on prosperity.

Jul 15, 2014
Strange when any unsubsidized renewable becomes cheaper on a 24/7 basis than unsubsidized fossil or nuclear energy I will gladly join you in the happy dance.

Jul 15, 2014
You think fossil fuels/nuclear aren't currently being subisdized? Think again.
http://en.wikiped..._country

They are getting WAY more than renewables...and are STILL more expensive (even after having 50/more than a hundred years for nuclear/coal and oil respectively to become efficient at what they do)

Jul 15, 2014
First of all I did not claim that fossil and nuclear do not get tax breaks. I wanted to compare every energy source without any subsidies. Secondly, the subsidies to fossil and nuclear consist of lower tax rates on certain parts of their infrastructure investments. The subsidies to solar and wind consist of payments made by governments to the industry. In on case you have an industries that pay less taxes than they normally would and in the other you have industries that pay no taxes and receive government subsidies. That is quite a difference!

Jul 22, 2014
You think fossil fuels/nuclear aren't currently being subisdized? Think again.
http://en.wikiped..._country

They are getting WAY more than renewables...and are STILL more expensive


That is simply a lie.

Nuclear power in the US for example gets 22 times less subsidies than renewable energy when you put it in proportion to how much of the total grid load the different forms of energy actually supply.

You're making the fallacy of counting the total sum over how many decades, when you should be counting subsidies per unit energy produced. Of course nuclear power, or fossil fuels, have recieved more subsidies in total because they've been in use for far longer and they've produced tons and tons more energy!


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