Clean Fleet Report - MIRAI revisited

that guy's article read more like a PR campaign. He never bothered to address that fuel is $12 to $15 / litre - once the hydrogen costs that are rolled into the car expire. Never mind that the fuel tanks have to be replaced, as does the platinum stack, & the high pressure fuel lines that become embrittled, the longer they are exposed to hydrogen.
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Huh, I use cup holders for drinks! Most Americans use them for this purpose.

 

10 years the fuel tanks have to be replaced. No different then having to replace battery packs. All cars will need big ticket items replaced as they age.

 

agreed - that SOME things may need replacing around 10 years. But even if an engine block needed to be replaced (more likely just rework) at 10 years 120K-150K miles, many DIY might be willing to take a crack at it - on their own. There's even a batch of folks on YouTube showing the process for replacing/rebuilding battery packs. A couple PC members are even making a business at rebuilt & new packs for Prius. Stupid or reckless drivers mean there's a lot of good salvage yard traction pack inventory .... as there is for standard automotive parts. But an entire fuel system for hydrogen? Platinum stack? Fuel system running throughout the car? Fuel tank? As well as the accompanying sensors for those components? That would be a beast that few ought to even consider trying to tackle. And rebuilding traction packs or engine blocks? Doable - and at an affordable price. If an engine block or traction pack are near their life expectancy, you can still nurse it along for more miles. But a 10K psi fuel system? DOT says 10 years & that's it. Got to go get off the road & it HAS to all go.
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Yep - you're hard-pressed around here now days to find a car with simple crank roll up windows ..... although we do have a friend with a Corolla maybe 5 years old that still has them. Eventually these simple parts will become more expensive just because it's a matter of supply & demand, where Mass produce parts are less expensive than those that are fewer and farther between.
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Fuel cell cars also have that battery pack.

Pressure fuel tanks on road vehicles require annual inspect in addition to the end of use date. Not an issue now, because I think the states hydrogen cars are available in already have annual inspects, but not every state does.

Saw that on the Ranger. Put ABS rotors on the non-ABS truck because of the price.

 

Cup holders are used daily in my Prius, can’t imagine not having them. I only need two, not sure who would need 19 or so in a car.

 

When the Prius came out, the first thing buyers became concern about was the life expectancy and cost of a new battery pack. Well 20 years later, the cost has dropped and like you said people can do it thenselfs. So it’s not unreasonable to assume in 20 years the same will be for Hydrogen replacement parts.

 

The hydrogen tanks in the Mirai have a 15-year service life, according to the Warranty & Maintenance Guide (PDF) and the Repair Manual (more info).

Any competent, careful auto mechanic who can read and follow instructions should be able to work on a Mirai. Indeed, that’s kind of the point—it’s an FCV, but it’s also a Toyota, with a model code, Repair Manual, listings in the Electronic Parts Catalog, and extra-cost, dealer-installed floor mats. There are some unique special service tools, of course, but they’re all supposedly in the distribution system.

The biggest problem with owning one, in my mind, would be parts availability: so few have been sold, relatively speaking, that if Toyota were to end support after the eight-year fuel cell system warranties expire, it’s unlikely there would be aftermarket sources for the fuel tanks or other consumable parts.

California has no state inspection of private vehicles, other than the Smog Check program, from which fuel cell vehicles are exempt. Do any states regulate the hydrogen tanks in FCVs as unfired pressure vessels?

 

I wouldn't work on, nor would I want my neighbor working on, a high pressure hydrogen fuel system in a residential area.

Then the hydrogen tank can't be refurbished like a traction battery. Those replacing it will be limited to buying new mostly. Used will be available, but those may only have a few years left before they need to be replaced. Then when full, these tanks are containing 10k psi of hydrogen, do we want tanks from crashed cars going back into service?

The price for new tanks could come down in time, but that depends on the cars being adopted in numbers.

The 15 years isn't a service life; it is an end of use time for the tank that starts from date of manufacturer. A factory made car will get virtually the full amount of that time. It will be an issue when it comes to used tanks as replacements, or if you are looking at 'new' CNG tanks on ebay for a CNG conversion.

Like working on HVAC, a shop working on a hydrogen fuel system will need the proper equipment to empty and fill the system. Considering the pressures and equipment maintenance involved, I don't see something independent shops taking up.

Vehicle fuel tanks fall under US DOT regulations, and hydrogen tanks should follow the ones for CNG. This is a nice summary.
Alternative Fuels Data Center: CNG Fuel System and Tank Maintenance

I got the one year wrong. The federal regulation here is 36k miles or 3 years, whichever comes first. Likely where I first read about it was talking commercial trucks. They are more likely to be converted to CNG, and 36k miles is something they can see in a year.

 

That’s a fair point. For updating the “DO NOT REFUEL AFTER” label, the Repair Manual says, “From the 2 hydrogen tank assemblies installed to the vehicle, use the Tank Inspection Passed date of whichever tank has an older date, and starting from a point 1 month before the Tank Inspection Passed date, record a month/year that is 15 years in the future.”

The Warranty & Maintenance Guide says to inspect the hydrogen tank and other specified parts of the fuel system at least every 10,000 miles or 12 months, and the prudent owner would surely do this or have it done. The Repair Manual has a step-by-step On-Vehicle Inspection procedure.

I’m not aware of anything in NHTSA or other USDOT regulations that makes such inspections of private automobiles a legal requirement, though. FMVSS No. 304 just requires in S7.4(g) that a tank has to have a label stating “This container should be visually inspected [ . . . ] at least every 36 months or 36,000 miles.” It’s also not clear that standard applies to hydrogen tanks; its S7.4(f) requires the label to say “CNG Only.”

For the Mirai, I imagine the design standards might instead have included ISO 23273, SAE J2579, Article 17 of the Japan Safety Regulations for Road Vehicles and its various announcements and technical standards (page in Japanese; translations available from JASIC), and UNECE Regulation No. 134 (PDF).

 

Hydrogen cars probably are too new and of limited availability for a federal agency to make a ruling. The regulations for CNG tanks is a fair starting point though. The much higher tank pressures, and chemical nature of hydrogen, should make doing inspections more often prudent.

 

DOT regulates high pressure tank testing, referred to as a hydrostatic test. This is where liquid & pressurized gas overfills a tank to around 125% of its rated pressure, at a given temperature. A regular steel tank has to be disassembled (from all of its Plumbing) & tested every 5 years. Reinforced/wraped tanks like in the Mirai, & many other types of high pressure tanks (like CNG) need to be tested every 3 years.
CO2 and HPA Tank Hydrotesting [ZDSPB Tech]
I recall having it done on my aluminum & steel scuba tanks. The test would take between 4 to 8 hours. I would hope that auto manufacturers have spares, so you don't have to kiss off an entire day every 3 years. Or, maybe more efficient, have it done when other service also needs to be done, so the Lessie/owner isn't further inconvenience. There I go being hopeful, despite having to virtually order all parts nowadays when at the service centers. It took 6 months when a headliner under warranty had to be replaced by the manufacturer.
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Toyota’s own Repair Manual procedure for inspecting the hydrogen tanks includes only visual inspection and the use of a hydrogen gas detector; the tanks are not removed. I can’t find anything in a Toyota publication suggesting that hydrostatic testing is required or appropriate.

The DOT Hazardous Materials Regulations (49 CFR 171–180) do require requalification of gas cylinders, but they apply only to transportation in commerce and indirectly to employers through the OSHA compressed gas standard (29 CFR § 1910.101). I don’t think the regulations apply to hydrogen fuel tanks of in-use FCVs: non-commercial transportation in private motor vehicles is completely exempt (49 CFR § 171.1(d)(6)), and PHMSA has also consistently interpreted its regulations as not applying to vehicle fuel tanks unless they are being transported as cargo; see, for example, IR #11-0181 and IR #15-0135.

The situation is different for hydrogen fueling stations, of course; those must comply with 29 CFR § 1910.103 (or equivalent state standards) and local building and fire codes.