Hydrogen Barbque And Hydrogen Alarm

[belovelife]

ok, if we made hydrogen barbques that began spreading the hydrogen infrustucture

 

is it possible that an alram could be desighned just in case a bottle qwas lefrt inside a house

 

and the amount of hydrogen released from the tank reached fire potential levels

this would be similar to a regulator on the tank, but it also tests the air for hydrogen

[Lancewen]

ok, if we made hydrogen barbeques that began spreading the hydrogen infrastructure

 

is it possible that an alarm could be designed just in case a bottle was left inside a house

 

and the amount of hydrogen released from the tank reached fire potential levels

this would be similar to a regulator on the tank, but it also tests the air for hydrogen

 

As much as I like the

I'm not sure I'd want to pay the high price for it, just to barbeque.

[belovelife]

$5 a kilogram goes a long way

 

 

plus its co2 free,

Edited June 28, 2012 by belovelife

[JMJones0424]

$5 a kilogram goes a long way

 

I haven't purchased charcoal in a few years, as I now make my own biochar and use larger chunks for cooking, however, a ~7.5kg bag of Kingsford charcoal regularly sells for $7-10 US. I haven't priced hydrogen locally, but lets use your figure of $5/kg.

 

To compare apples to apples, we need to determine the energy density. Wikipedia lists the energy density of Hydrogen at 123MJ/kg, at $5/kg that's 24.6MJ/dollar.

 

Finding the energy density for charcoal was a little less straightforward. The same wikipedia chart lists wood at 16.2 MJ/kg, and charcoal is essentially wood with all of the substances that impede combustion driven off, so it is reasonable to assume charcoal would be at least 15 MJ/kg. A google search gave figures ranging from 10-25 MJ/kg, but in order to be conservative, let's say we have a 7.5kg bag of charcoal purchased at $8 US with an energy density of 15MJ/kg. This works out to about 14.1MJ/dollar.

 

Propane, another popular outdoor cooking fuel, costs around $3/gallon to refill, or about $1.58/kg. With an energy density of 46.4MJ/kg, thats about 29.4MJ/dollar

 

Unless my assumptions were widely inaccurate, Hydrogen at $5/kg is considerably more economical than charcoal, a result I was not expecting. However, propane is slightly more economical. Another thing to consider is that when the cooking is finished, one can turn of the gas, but charcoal is not usually extinguished and saved for later use, making charcoal even less attractive economically. I do not cook on propane, as I like the flavor that burning wood imparts to the food, but if one is already using propane, switching to Hydrogen doesn't seem to be too terribly uneconomical. Is cooking with Hydrogen roughly comparable to cooking with propane?

[Lancewen]

$5 a kilogram goes a long way

 

 

plus its co2 free,

 

But you would still have to pay more for the high compression containers and also find a conversion kit for the barbeque if you could even find one. I don't believe anyone makes them yet and when they do, I'm sure they won't be cheap. But I'm sure many people will want the cleanest burning barbeque they can get.

[JMJones0424]

But you would still have to pay more for the high compression containers and also find a conversion kit for the barbeque if you could even find one. I don't believe anyone makes them yet and when they do, I'm sure they won't be cheap. But I'm sure many people will want the cleanest burning barbeque they can get.

 

Indeed, I should have known better and read belovelife's source. The linked source does not claim $5/gallon at all. In fact, it claims:

The station requires approximately 80 kWh of electricity to generate, compress, and dispense one kg of hydrogen fuel. Based on the average cost of industrial electricty in the U.S. of 6.2 cents/kWh, the energy cost of each kg of hydrogen would be approximately $5.00. Since HSU pays more for electricity, the cost at this station is higher.

 

The quoted price of $5/kg is only the wholesale price for the generation and storage of the hydrogen, not the retail price. And worse, it's using a price for electricity roughly half of what is normal in my area. So not only is propane more economically efficient at this time, it appears to be many times more economical. Even charcoal is more economical, and depending on energy sources for production, may even be more CO₂ neutral than Hydrogen.

 

A conversion kit for a grill shouldn't be terribly expensive, as it would just require different jet sizes for the burners to compensate for the different burn characteristics of Hydrogen over LPG. However, the tank and regulator for Hydrogen could conceivably be much more expensive than LPG, as the pressures involved is orders of magnitude higher for Hydrogen. Because I did not check the source provided, I was working under the incorrect assumption that consumer preference was the only obstacle for Hydrogen fueled grills. This view is not supported by belovelife's source in any way.

 

However, I assume the easiest way to accomplish the original goal of belovelife's post, rather than incorporating some kind of leak detector in the tank or the regulator, would be to add an odorant to the hydrogen, as is done with natural gas and propane, so that a leak is easily detected.

Edited June 28, 2012 by JMJones0424

[belovelife]

cooking on hydrogen

[belovelife]

plus, i believe as hydrogen becomes more widely availible the price will drop

[Lancewen]

I hate to say this but that small print was to much for me to read.

 

Has anyone thought about cooking with Acetylene? It has a wonderful green flame when it burns.

[CraigD]

ok, if we made hydrogen barbques that began spreading the hydrogen infrustucture

:thumbs_up I think this is a good and clever idea. That it’s mostly a publicity stunt doesn’t change my opinion in the least – carbon neutral fuels need publicity.

 

I’m far from certain H₂ gas or liquid will ever be a practical fuel for use in as many applications as CH₄ (methane) gas, C₃H₈ (propane) liquid, and other hydrocarbon fuels, either for combustion, or electricity-producing fuel cells. Nonetheless, increasing awareness of its usefulness is, at very least, valuable as an improver of science and technology education.

 

is it possible that an alram could be desighned just in case a bottle qwas lefrt inside a house

 

and the amount of hydrogen released from the tank reached fire potential levels

this would be similar to a regulator on the tank, but it also tests the air for hydrogen

Unlike methane and propane, I don’t think there’s much cause for concern about hydrogen gas leaks.

 

H₂ is much lighter than air, and such a small molecule it escapes from practically any container that’s not purpose-built to contain it, and some that are. It’s chemically reactive, so has a short lifetime in the air before compounding with various molecules.

 

In short, unless you live inside a steel-lined concrete dome (eg: a nuclear reactor vessel), you’re very unlikely to experience the danger of an explosive “hydrogen bubble”.

 

$5 a kilogram goes a long way

A bit more careful reading and cost-accounting of this brochure is needed.

 

It describes a self-contained, utility-supplied electricity-powered hydrogen refueling station, intended to support a small (1 or 2) fleet of hydrogen fuel cell-powered cars or light trucks. This approach is a valuable and attractive one, because it doesn’t require a large delivery system to work – in short, just plug it in, add water, and in a few day, you can begin refueling your H-powered car.

 

The US$5/kg cost, however, considers just the cost of electricity. The major cost for such a system, as I calculate it, is the station itself. The one in the article cost $676,690. While much of this was research and unusual costs due to its prototypical nature, even if mass produced, I’d expect such a system to cost at least as much as a small gas pump station. For estimating purposes, let’s say a mass-produced version of the system costs $250,000, and has an expected lifetime of about 10 years. Over its lifetime, it will produce about 9130 kg of H₂.

 

Adding this cost to the $5/kg cost of electricity gives about $33/kg. There would, of course, be other costs, such as container refurbishment and replacement, rent, labor, and insurance, and, of course, whoever did all this would likely want to make at fair profit, so my guess would be a final cost to the consumer of around $50/kg.

 

This is an impressively low cost, given that present day H₂ costs around $100/kg, but far from cost-competitive with LPG, which can be bought for around $2/kg. C₃H₈ has about 1/3rd the energy per mass of H₂, for a cost of about $6/(kg of H₂ energy equivalent)

 

Bottom line, cook’in with hydrogen will cost you about 6-10 times as much as cook’in with propane.

 

plus its co2 free,

True, and the whole point of replacing hydrocarbon with pure hydrogen fuels.

 

It’s important to note, though, that a hydrogen flame (or any flame hotter than about 1315 C) in open air creates some pretty nasty pollutants, especially NO_x (nitrogen oxides).

 

It’s not difficult to circumvent this problem by reducing the burner system temperature with stainless steel wool/mesh, as described in the wonderful 1993 Home Power article you cited upthread. Alas, this pretty much rule out having pretty flames, but primary purpose of a stove is to cook, not look pretty. :)

 

Bottom line for this consumer - if you can get a H₂-burning grill and a H₂ tank exchange to a store near me, I’d buy it, even though I’m not much of an outdoor grilling fan. The green/cool factor is simply irresistible. :thumbs_up

[belovelife]

interesting, i thought if you say left the tank in your garage, it would leak, as hydrogen being so small does, and if you turned on your car in the morning, the garage might explode

 

 

 

so you are saying that the hydrogen would combine with things like dust particles, and vent through and hole before enough would build up to cauise an explosion?