[Zanstel]

Similar to propane or liquid petroleum (LP) gas, ammonia is a gas at normal temperature and atmospheric pressure but a liquid at higher pressures (about 150 pounds per square inch at 75 degrees Fahrenheit). So it can be stored and transported as a liquid but used as a gas.

It has half the energy density of gasoline. And ammonia is barely found in nature, certainly not in the same convenience and concentration of petroleum reservoirs. So how is it an improvement of propane?

It is not only about energy density. Any hydrocarbon requires carbon (so obvious), so it needs come CO2 recycling. In a sustainable close circle economy, in the future, CO2 could be obtained from biomass. But this has limitations by total (sustainable) production worldwide. Capture CO2 from air raises the energy requirements a lot. Hydrogen has been shown as the solution, but ammonia could be a better alternative as a whole. Although it has worse energy by weight, it has better energy by volume and it is easier to store.

For small cycles, batteries it is the obvious solution. But when we need to store high levels of energy, like season storage (from summer to winter, for example), fuel could be cheaper, even it requires to make greater energy capture (to compensate energy loses). Other solutions, like flow batteries could be ok.

[Tanada]

Similar to propane or liquid petroleum (LP) gas, ammonia is a gas at normal temperature and atmospheric pressure but a liquid at higher pressures (about 150 pounds per square inch at 75 degrees Fahrenheit). So it can be stored and transported as a liquid but used as a gas.

It has half the energy density of gasoline. And ammonia is barely found in nature, certainly not in the same convenience and concentration of petroleum reservoirs. So how is it an improvement of propane?

Not sure why we are comparing Ammonia and Gasoline, the useful metric is Ammonia and Hydrogen. Hydrogen has a horrible energy density as a compressed gas and is very difficult to liquify and store as a liquid. Using Hydrogen to power cars is nuts when you can convert that hydrogen to Ammonia and get much more energy stored on your vehicle than you could ever get with hydrogen gas tanks. With half the energy density of Gasoline but the capability to be used in a standard ICE gasoline fuel replacement role that means if I convert my car I can go 150-200 miles instead of 300-400. Either way my regular driving is less than that a week so its just a weekly fill up and don't worry about it.

[hvacman]

I'll tell you why you won't see any ammonia-powered vehicles anytime soon. I'll skip the net energy issues for now.

How many of you are running ammonia refrigerators or air conditioning in your house? What? no one? Why not? Ammonia is about the best refrigerant you can get for AC and refrigeration. Efficient. Inexpensive to make. Works well with basic steel and iron compressor and piping materials. All the refrigerators in the early 20th century used it and major industrial refrigerated warehouses still use it. What happened on the consumer side?

Just a few deaths from leaks, some fires, and a lot of people not-killed-but-overwhelmed by the pungent odor. That is what sent DuPont on the search for a set of new refrigerants that were almost as efficient, non-toxic, odorless, and chemically stable. They found them. Chlorinated fluorocarbons, also known as "CFC"'s. Freon 12 (generically known as "R-12") was a huge hit. It was in every refrigerator. Freon 22 also was big in the AC market. CFC's dominated the market through the 1990's, when ozone depletion became a big deal. Seems the CFC's when released to the air, would not break down until they rose to the stratosphere. There the radiation would break them and the freed Cl would react with the ozone. R-12 production was phased out. Try to buy some now for your old automotive AC unit. R-22 is being phases out. All new AC units use R-410a. The good news - CFC emissions have plummeted and the ozone layer is now slowly recovering. (If only we could sort out the CO2 situation as easily...)

Ammonia is only used at the consumer level as a refrigerant, in minute portions, for those very-special gas-fired refrigerators used in RV's. It takes an exotic ammonia-hydrogen-water blend to make the magic of refrigeration powered only by a flame. If you are technically-interested how this works, it is a special kind of "absorption" refrigeration cycle called the Platen-Munters cycle.

https://en.wikipedia.org/wiki/Absorption_refrigerator

[hvacman]

All is not well on the Hydrogen Highway

Excerpt for and new Green Car Reports article:

While they enjoy driving their cars, early lessees of hydrogen fuel-cell vehicles in Southern California are complaining that they can't reliably fuel them at the handful of stations now supposedly operating in their region.

The stations are frequently inoperative, they say, closed for days or weeks at a time.

Moreover, when the stations are functioning properly, they sometimes can only fuel one or two cars before an hour-long wait is required--and some stations can only fuel the cars to half-full.

A private Facebook group for drivers of the Hyundai Tucson Fuel Cell SUV overflows with complaints about these issues, and the lack of accountability among the several different parties who oversee pieces of the nascent hydrogen fueling infrastructure.

[url]
http://www.greencarreports.com/news/...ions-dont-work[/url]

[Graeme]

But Toyota is very determined:

Toyota Moves Forward On Rolling Out Its Mirai Fuel Cell EV

In terms of publicity, Tesla Motors has pretty much cornered the electric vehicle scene. However, Toyota did promise delivery of a hydrogen fuel cell electric vehicle for the hot California auto market this year, and the company is cranking up the ol’ publicity machine in advance of the expected October 2015 arrival date of its hydrogen-powered Mirai sedan.

None of this is bound to cause any sleepless nights for Elon Musk, CEO of the much-publicized battery electric vehicle company Tesla Motors, who once famously described fuel cell electric vehicles as BS.

However, BS or not, Toyota is going full steam ahead with rollout plans for the Mirai FCEV (fuel cell electric vehicle). Last week, the company announced the launch of a new online consumer request portal for prospective customers in California. Among the details are these:

The Mirai hydrogen fuel cell electric vehicle…has the highest EPA estimated driving range rating of any zero emission electric vehicle on the market, at 312 miles, and offers an EPA estimated 67 mpge city/highway/combined.

…MSRP will be $57,500 plus an $835 destination fee.

…Trailblazer Lease: $499 per month for 36 months, $3,649 due at signing

Three years’ worth of complimentary fuel.
Three years complimentary Safety Connect and Entune, including hydrogen station finder app.
Three years of 24/7 customer call support.

cleantechnica