Quote:
Originally Posted by Astro
With hydrogen fuelled vehicles the issue of whether hydrogen is fossil fuel derived or sourced from a green source is a significant one.
There may be technology on the horizon which will make green hydrogen a more efficient and cost effective fuel but the sceptic in me doesn't trust the oil companies. Am i alone in that?
I don't think they will let people off the fossil fuel hook until it is pretty much all used up. And they will develop clever ways keeping the public hooked.
I can see them marketing the greener hydrogen, with say 10% sourced from green sources. Then a few years later announce the even greener (and more expensive) 20% green hydrogen. And onwards and onwards with 100% green hydrogen being cheaply available just as the last few drops of fossil fuel have been refined.
I would be very happy to be wrong.
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I am a firm believer that the solutions of the future will be a combination of solutions.
I make discussions with you Astro, not for simple argument but to hopefully educate and prod the reader to think. I appreciate the back and forth.
I will first answer the sourcing of hydrogen as being green - or not. It is not green at this point as it is sourced mainly from natural gas. However, this is due to the cost. It is very low cost. At some point, fossil fuels will become exceedingly more difficult and expensive to extract and costs will rise allowing alternatives to compete. Unless we tax fossil sources to account for the environmental burdens they impose it may be a few decades for this to happen. But, if electricity becomes dirt cheap, there are several pathways that would allow us to continue with our modern, energy intensive culture though efficiency should always be underlying every move as that in itself is a "source" of energy.
I have made mention of the limits imposed on battery chemistry, but that does not kill battery power for many solutions. Hydrogen will have it's niche. I can see regions where cheap electricity already abounds that would allow basic electrolysis solutions to produce hydrogen. I live in one of those regions. And, there is already one local company that leverages these resources. My business lies along the Palm Springs energy corridor and the wind farms produce mega watts of electricity. The base loads are covered by a series of geothermal plants just east of us. The geothermal plants are best run at high loads as modulating their output is difficult. The wind farms taper and feather their output based on demands. We are right in the middle of the windiest time of the year. Many of the wind machines are idle as the load doesn't require them. A local company buys electricity at a greatly reduced rate from the excess electricity available to the power company. They use a high pressure electrolysis machine to produce hydrogen and oxygen for industrial uses in the medical and tech industries. Of course this is an aside to the their standard condensation of air to gain other gas types. And, it was a way to get a state grant. But it underlines what we can do to use excess electricity that often is dumped or the capacity is not used.
As to under road charging schemes - they have their place and their problems. I do have a background in electrical engineering overlaid on my industrial and mechanical engineering as I eschewed the doctoral path to gain broader knowledge instead of deep specifics. It does allow me to talk with a large number of people in various fields with some basis of understanding. Under road solutions will have to struggle with various problems. Economics is just one of them. The idea of the road charging technology is to extend the range of electric vehicles. But fast chargers will mitigate that advantage as several people have mentioned already. As costs of batteries drop, more battery range can be added to a vehicle. But, if you add a road charging system you will incur a significant weight penalty to mount the sympathetic coils under your car. Why not just use the weight to add more battery range? Also, alignment of the coils is critical. How do you drive straight and true? Yes, automated driving aids are already here, but roadway smoothness becomes paramount as proximity between the source coil and the sympathetic coil becomes important. A few centimeter difference can mean the difference between 85% energy transfer efficiency and 60%. Yes, this is for AC induction coils in the tens of hertz. You can extend the coil distance by going to the kilo hertz region and if you use the idea of Tesla's resonant coils as MIT did in some studies done a decade ago, you can go to the mega hertz region and transfer energy over meters distance. But now interference becomes a real issue as numerous devices use the KHz and MHz bands. Pacemakers are affected in the low Hz range. Charging roads are being tested and these issues are being addressed, but by the time they are addressed other solutions may become more plausible.
South Korea has a charging road that has a 7.5 Km length allowing a set of test buses to transit it's length in about 10 minutes charging a small battery pack that allows sufficient energy to complete a set loop. However, several cities have similar buses with similar capabilities running similar loops but that are charged with fixed underfloor induction coils in the 10 minute rest period allotted for driver breaks. These charge pads are a fraction of the 7.5 km under road charging section. On the other hand, an automated charging arm can do the same thing at the fraction of the cost of a charging pad. For personal vehicles, I think you can see some of the same arguments and solutions coming into play. Why pay for the large costs of an under road charging section when a charging pad will do the same thing at a fraction of the cost? Why use a charging pad when I can use an inductive paddle and ditch the weight of the under body charging coils and go from 125 Km range to 175 Km range? At that range, I'm going to stop anyways and let the wife out to run around and buy a 32 ounce drink that will force me to stop again in a couple hours. Just make fast chargers available at these stops and I'm good with the whole situation.
Back to fuel cells.
I was connected with Ballard back in the late 80's and one of the things that irked me was their insistence of myopically focusing on pure hydrogen fuel cells. These cells need pure hydrogen as they are easily poisoned by various compounds. I was a proponent of solid oxide fuel cells (SOFC). They can use various fuel sources and are less sensitive to poisoning. They are less efficient due to the high temperatures they run at, however, new material technology as well as catalyst advancements are pushing the operating temperatures of SOFC down to the targeted 600 degrees C and below. At those temperatures, more common materials can be used for structure and reliability increases tremendously. At that point, heavy payload vehicles can use Low Temperature SOFC (LT-SOFC) in a hybrid configuration with a reasonably sized battery pack and using hydrogen and oxygen from electrolysis trapped in a hydrocarbon such as methanol or ethanol with the carbon coming from carbon dioxide trapped flue gasses or distilled from the air.
All the above is plausible with the only trip up being the primary energy source. Since not all regions have cheap hydro, wind, solar or geothermal energy, a primary distributed source is needed. That comes down to our Western Societies overcoming the fear of nuclear power in all guises. I am a supporter of nuclear power. We have nuclear power technologies that bear investigation. Solutions such as liquid fluoride thorium reactors (LFTR) I have mentioned in the past. Even if we don't build them here in North America, the Indians and certainly the Chinese will as they have no choice but to investigate all avenues for future power and they do not have the opposition blocks we have here in the west.
Hydrogen is an energy carrier. It in itself is not going to solve our energy problems. But if we combine clean primary sources with hydrogen entrapped in hydrocarbons with carbon sourced from biosphere sources, we can cover all our current needs. The electricity stored in batteries powers our local needs. SOFC power our heavy payloads. The concentrated energy of hydrocarbons will power our heavy air loads. And yes, there will be a place for road charging solutions.