Riversimple and Fuel Cell Discussions

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It's still not very versatile, our i-Miev can outrun it, so it isn't a particularly powerful on either.

I've looked at commercial small 5kWh fuel cells, but it's just not cost effective, not even close. A small jet turbine could work, they light almost anything that looks like diesel, but they tend to be noisy and are not well suited for long running applications, although their power enveloppe is quite decent.

A small 20-30cc RC gas engine is a few hundred euros, but crafting that into a package useable as a heater and range extender at the same time will be quite the feat. Not impossible, and where do we put that in the i, it's significantly larger then the current parking heaters. http://www.hobbyking.com/hobbyking/store/__15380__RCG_15cc_Gas_engine_w_CD_Ignition_2_1HP_1_54kw.html

Still, that could deliver about a kW of power with 2-3 in heat. You'd want a good muffler though for something that runs 5000rpm constantly.
More publicity on the Riversimple:

I really like the concept of a small aerodynamic vehicle (Aptera, RIP), although I'm not thrilled at the concept of a very high pressure onboard hydrogen tank. Wonder what the weight of that tank and fuel cell paraphernalia and their batteries is, as making it a pure BEV would perhaps be a simple alternative?
Not sure of H2 pressure either, but I stopped at a local CNG pump the other day. The pump has 4,700 PSI behind it :shock: . I wouldn't want the nozzle to break off of that tank.
The big question is . . . where do you get your hydrogen from?

You can extract it cleanly with solar panels from water, via electrolysis. Trouble is, it's about 3 to 4 times less efficient to obtain a unit of energy this way than it is to use those same PV panels to recharge batteries.

So, to obtain hydrogen economically and at a scale to make it a more practical transportation fuel, one has to use a steam reformation process with natural gas to extract it. Even here, the process of expending the energy to make the hydrogen has led many to observe that you're better off both economically and ecologically to simply run a conventional internal combustion engine vehicle on natural gas. And guess what? A well designed battery EV wins in both operating cost and cleanliness when compared to a natural gas car.

Hydrogen is essentially the petroleum industry's version of what they want and electric car to be. The fuel has to be made at a refinery and moved to distribution stations. Forget pipelines. It literally leaks through those sort of metal structures, so it has to be trucked everywhere.

Then, the consumer has to go somewhere to get it piped into their car . . . and at an alarming 10,000 psi (at least in the case of the Toyota Mirai.) There's also the price of hydrogen refueling stations, which are far more expensive than even the most exotic Quick Charge facilities for our EVs. Meanwhile, I can also charge at home overnight (and more often do than not) with plain ol' 120V alternating current.

A hydrogen car essentially has to be a battery electric car to begin with, since a fuel cell can't be throttled in the same way that a controller on an EV elegantly interfaces the battery with the motor. A fuel cell also can't store electricity. So, electricity regenerated from the motor when the car is going down hill has to be routed to batteries.

About 15 years ago, I briefly bought into the idea of hydrogen fuel cell vehicles, like so many others. But the more I looked at it critically, the more I could see that it was ultimately going to be a distraction getting in the way of battery electric vehicles enjoying wider adoption. The problems with batteries (ie: durability, weight, price and ability to quick charge effectively) are now well on the way to being solved. Connect those same batteries into the grid and you now also have a way to more easily integrate wind, tidal and solar energy into it. We then can, more often than not, drive our cars completely from clean, renewable energy.
Couldn't have said it better myself. They want Hydrogen, but they want to get it from natural gas. Well, why don't we save a step and either:

A.) Run vehicles on natural gas directly? or,
B.) Use the natural gas to generate electricity to run BEVs?

Both options already have existing infrastructure, and both transport much better than Hydrogen anyway.

I've noticed that Hydrogen as a fuel source for vehicles only gets talked about when BEVs pose a threat to oil. Once BEVs go un-noticed or disappear, so does Hydrogen. It happened in 2003, and it's happening now. Talks of Hydrogen cars was one factor in the demise of the BEV revolution in the late 90's.

Now, the problem with trying to run cars on natural gas or natural gas-derived Hydrogen. Natural gas, right now, is still more expensive than gasoline (local station cost $2.20 per gasoline gallon equivalent, while gasoline is at $2.03 locally). That's with minimal demand from cars. Once you start driving half a million cars on natural gas or Hydrogen from natural gas, that price is going to shoot up to where gasoline was three years ago. Has anybody noticed any effect on their electricity prices from adding about a million EVs to the global fleet? The gas price crash was due to a lot of factors, but one big one was demand destruction caused by EVs. Funny how a monopolized energy source suffered so badly (for the companies selling oil) by EVs, but how stable a diversified energy source (the electrical grid) stayed under the additional demand. Not only that, but because of the high efficiency of a lithium-ion based electric drive system, overall energy consumption of an EV is 50-80% lower for driving the same distance. Over the last 3 years and 30,000 miles, Bear has consumed 8,114 kWh, roughly 6 months of production for my solar array. The Cavalier it replaced would've consumed 1,200 gallons of gasoline to drive that distance, which is a total energy consumption of 40,200 kWh (each gallon of gasoline contains 33.7 kWh per EPA). So, a BEV reduced my transportation energy usage by 80% over an ICE. To generate and use Hydrogen instead of a lithium-ion battery results in about 30% of the energy consumed in separating the Hydrogen gas being able to be used when the Hydrogen is joined with oxygen at the fuel cell. So, a Hydrogen car's energy consumption would be 27,046 kWh when the Hydrogen was separated from water using electrolysis.

In summary, electricity usage for 30,000 miles of driving:

BEV - 8,114 kWh (including heater and AC usage)
H2 - 27,046 kWh (including electrolysis stage)
ICE - 40,200 kWh (33.7 kWh per gallon at 25 MPG)

Can't argue with the charge/discharge efficiency of the lithium ion battery.
I know that you folks are probably right at the moment, but I just like the looks of the car and what it stands for. :)

And just maybe someone will figure out a better and cheaper way to accomplish hydrogen re-fueling (as "they" are figuring out better and cheaper battery technology). It will be worth it to see how Riversimple handles it.

There were naysayers with the EV-1 too!
I know. Hydrogen is some pretty impressive technology. The efficiency isn't there...yet.

The way I see it, though, there is already a nationwide infrastructure to generate and distribute electricity, and it is found in nearly every building. The only equipment needed to use that infrastructure for cars are plugs (EVSE). For faster charging, that's taken one step further by placing larger versions of our on-board chargers in stationary locations and connecting that charger directly to our battery packs (Superchargers and quick chargers).

For Hydrogen, and entire infrastructure needs designed and built, new systems need manufactured to dispense the fuel, and new storage technology needs created. Also, provisions for home refuelling are even farther out in the development cycle.

While both battery and Hydrogen technology are great, for the end user, I don't see Hydrogen beating the simplicity of plugging a BEV into a 120 volt outlet and the car charging automatically. People hate gas stations for a reason, but they're fine with plugging in their cell phone every night.

I just hope that a solution we're driving today doesn't get totally ignored for something that's "right around the corner".

(Side note, I would love to have an EV1. Mostly normal-looking car with un-matched aerodynamics (.19 cD) and energy efficiency, with range that's only been surpassed by Tesla so far. In fact, the Model S is the most aerodynamic EV you can buy (.22 cD). I can't wait to see the aero rating on the Model 3.)
I hope Riversimple succeed to come up with a working small packaged system of H2 storage & fuel cell. I think H2 can be a great range extender for a BEV, especially for the occasional supplement. Even with such low efficient for H2 photolysis, it may work if it is not the primary energy source

The Urbee with 0.15 Cd ain't bad, too bad it's just vaporware

Although I'm still skeptical of hydrogen in general, there is something to be said for a sporty little runabout like the Riversimple. Even if the fuel cell version doesn't get going (there is nothing said in the video about where the fuel is coming from, unless there's something going on with hydrogen infrastructure in England that I don't know about,) an all-battery version of a car like this would be immediately welcome.
Anybody want to help crowdfund Riversimple?


This their updated site, I believe.
More updates on Riversimple from the London auto show including two additional concept vehicles:


I did sign up for their newsletters/announcements and did send an inquiry as to what their hydrogen distribution network would look like, but they haven't gotten back to me yet. I am not sure that they know what it's going to look like. :shock:
The problem with H2 is the problem in getting it, transporting it and making it work in a vehicle. Although hydrogen is the most common element in the Universe, once it bonds with something else, it is really hard to separate it back out. This has all been covered before so no use going into that again. A question asked earlier was what kind of pressures do you compress H2 to? Well, 10,000 PSI seems to be a useful working pressure to store it if you want any kind of range at all. That is because there is very little energy in a cubic foot of H2 so you need to pack a lot of it in the tank. CNG cars run at 3600 PSI @ 70 degrees F. There is more energy in a cylinder of CNG at 3600 PSI than the same size cylinder of H2 at 10,000 PSI. BTW-if the ambient temperature is higher, then CNG up to 4200 PSI can be put in to equal a full tank at a lower temperature. Anything higher than that is used in the station to compress the storage cylinders (usually around 5000 PSI) so you can fill vehicles to 3600 psi and have a reserve without constantly starting the station compressor--sort of like your home compressor but much higher pressure. So, if you add the cost of manufacturing H2, transporting (all by truck as you cannot put it in a pipeline) compressing it and building the fueling infrastructure along with adding a "range extender" fuel cell and tanks to what is essentially a BEV---it makes no sense at all. Maybe in the future there might be some economic and environment reason for this but I would think the battery technology advancements will always be ahead of hydrogen rendering it useless for vehicle propulsion. Right now H2 is an answer looking for a problem. However the problem is being solved with EV's. I also think that "big oil" has a vested interest in the promotion of H2 because unlike EV's and CNG vehicles, which can be "fueled" at your home, the infrastructure to fill H2 vehicles has to be at a "gas station" owned by someone with deep pockets who wants to empty your pockets with snacks, beer, cigarettes, lotto tickets and overpriced H2 at the pump :twisted: ! We are already driving the future---lets keep it up.
I agree 100%. The Model 3, Gen2 LEAF, Bolt, and Gen2 BMW i3 will all have at least 200 miles of range without much of an increase in price from the current EVs. For lithium-ion based EVs to be this competitive with gasoline after only 6-8 years of dedicated development is mindblowing.

Many of the hurdles to EV adoption either have been solved or are close to it, yet Hydrogen suffers the same setbacks as it did 13 years ago when it proved to be a near fatal distraction from BEVs in the US. In reality, there's little efficiency improvement in swapping an ICE for a fuel cell. Even then, FCVs only use the fuel cell like a hybrid car uses the ICE. The underlying propulsion system is still a battery-powered electric motor. Other than vested interests, a Hydrogen fuel cell in a vehicle just doesn't make any better sense than just burning gasoline or CNG directly. The backbone infrastructure for both exists for the most part.

I can take my i-MiEV's fuelling station with me in the form of a cord and plug in anywhere. Try doing that with an H2 or CNG compressor.

As for the Riversimple Rasa itself, I like the idea of a small, efficient package for a car (with some design cues from the 1st Gen. Honda Insight and Tucker 48), but I don't like their choice for the fuel. Something like that should be able to do 100+ miles on a 16-20 kWh battery.
Agree with everyone's comments regarding hydrogen, especially siai47's "Right now H2 is an answer looking for a problem". Inasmuch as the small and very aerodynamic package appeals to me, a couple of months ago I had left a query for Riversimple asking if they had plans for an all-electric version - no answer.
This from the Riversimple Facebook post:


It looks like there may be a viable hydrogen network coming after all.

Its a wait and see.