Hybrid Vehicle – Why Fuel Cells are going to make it

In the news of the past few months there have been numerous items on big car manufacturers making a hybrid vehicle with a fuel cell. The first one is expected to roll out of the factory around 2015. In the discussions around fuel cell powered vehicles, often the discussion goes over to efficiency, which for the total cycle of well-to-wheels for a hydrogen powered fuel cell is less good as for example a pure electric vehicle powered by a not so efficient power plant. Despite this lower efficiency, fuel cells are the hybrid way to go, for one big reason only: convenience.  

How the Fuel Cell works

 

First a recap on the efficiency of a hydrogen powered fuel cell hybrid vehicle. It starts with creating the hydrogen, either by electrolysis of (pure) water or reforming of natural gas. Preferably the water is pure, though it is possible to use water with some impurities, it will be a less efficient conversion process to start with. After the the hydrogen is made, it is a common practice to compress it, a pressure of 350 bar is not uncommon. This is another energy sink in the process chain from well-to-wheels, but it allows one to haul along a significant amount of extra hydrogen compared to non-compressed hydrogen.

 

The conversion from hydrogen in the fuel cell to electricity is theoretically around a maximum of 50-60%, in practice this is usually a bit lower, though at the designed operating points and conditions this does not deviate significantly. The rest of the drive train in a fuel cell hybrid vehicle does not differ much from a pure electric vehicle; an electric converter, an electric motor and a battery (sometimes adding its own converter). The result is that the well-to-wheel efficiency for a hydrogen fuel cell vehicle is somewhere between 25-30%, depending on the source used for the creation of hydrogen. For more details on the well-to-wheels efficiency of hydrogen fuel cell vehicles, please check out the report from EFCF and an article at Electropaedia.

 

The well-to-wheel efficiency of a fuel cell vehicle is better than the efficiency of the internal combustion engine, but it it less than the well-to-wheel efficiency of the pure electric vehicle. In the current state of technology however, the pure electric vehicles have the best efficiency, but the shortest range. The fuel cell vehicle provides the possibility for clean transport, has a longer range, but misses a lot of efficiency when compared to the pure electric vehicle. The biggest motivation to use the fuel cell application now is for the increased range, take for example the Mercedes B-Class F-Cell in Floriday, which has a range of 400 miles, while an electric vehicle has around 100 miles of range (not counting the Tesla Roadster, but that is a different price range as well).

 

 

The Mercedes B-Class F-Cell, currently being used in a pilot project in Florida

 

With the current prices for fuel cell vehicles they are not really competitive with the electric vehicle, but if the prices would be comparable and even hydrogen would be readily available at the gas stations, fuel cell vehicles would allow people to travel longer distances without having to stop for a refill and still be green. The only real threat for a fuel cell hybrid is the speed of the technological advancements; the advancements with fuel cells, but also for the pure electric vehicle.

 

 

The success of the fuel cell hybrid will really depend on how the technological developments will go for battery technology, quick charging and inductive charging. All the mentioned technologies have the potential to increase the range of the electric vehicle, help speed up the refill and increase the convenience of the technology and limit the area in which a fuel cell vehicle will be beneficial for people.

Hybrid Vehicle – Rediscovering the canals

Some time ago (December 2009) there has been the launch in Amsterdam of the Fuel Cell Boat, a hybrid vehicle powered by a Hydrogen Fuel Cell and used to guide tourists around in Amsterdam, showing them the best spots on the famous canals. I’m curious how this boat is doing now, the latest update from the website has been ages ago.

The Fuel Cell Boat in Amsterdam

After the launch of the Fuel Cell Boat (early 2010), there was the launch of an electric boat in the canals of Utrecht, which is used to supply the shops in centre of Utrecht. It has a large crane to load and unload containers of goods at street level. Initially this was just used for the restaurants and bars, hence the earlier reference as ‘Beer Boat”, but it is now also used to supply other shops with.

The `Stroomboot` in action

It is a nice example not only of sustainable transport; as there are no more emissions and noise in the old centre of Utrecht, but it also preserves the canals and allows shops to have refills at a more convenient time. Heavy trucks are only allowed into the city centre at specific times, so loading a truck will not hinder pedestrians in the shopping areas. On top of that, there is a limit to the total weight of such trucks, so as to not damage the old bridges. How many win-win-win situations can you create in a single sustainable solution?

The Amsterdam hybrid cargo boat is put into its natural habitat

In Amsterdam the second cargo supply boat is found, a similar vessel, though hybrid, is roaming the canals there, for the exact same reasons as in Utrecht. These ships are manufactured by Bocxe from Delft and Koeleman Elektro from Mijdrecht for the electronics. The aim is (obviously) to sell more of these beauties and replace heavy trucks by transport through the canals.

 

These canal boats are the new retro; the canals have been used a lot a long time ago, until the introduction of the (ICE) trucks which made supply a much easier task. Now, with the trend to provide sustainable solutions for everything the canals have become a viable option again and provide additional benefits as well; not just the environment profits, also the old canals and bridges are saved and shops can be supplied again in the middle of the day.

 

 

To think that in most (Dutch) cities these canals have been filled up and replaced by wide roads, so the trucks could get in. Perhaps with the current wind of change some cities will consider digging out these canals again, running their supply by such boats and gain a tourist attraction in the process.

Sources:

Fuel Cell Boat (English)

Afdeling Bis Utrecht (Dutch)

Schuttevaer (Dutch)

Hybrid Vehicle - B-Class: revealing figures

This month Mercedes Benz will reveal their new hybrid vehicle, a converted B-Class which is now powered by a Hydrogen Fuel Cell. Following this, the vehicle will be leased from December this year in California for a test. California already has the so called ‘Hydrogen Highway’, a highway with conventional gas stations which also offer hydrogen on their menu. Although the initial plans for this highway was to have more stations with hydrogen available, the network would be sufficient for driving in California.

 

Revealing the new B-Class Back to the new B-Class, it has a 136 horsepower electric motor which is powered by 3.7 kilograms of hydrogen. The hydrogen is stored at a pressure of 700 bar and is supplemented by a 35 kW battery (though I assume they mean a 35 kWh battery). The battery is nicely tucked away under the floor, like it is with the A-Class. The total estimated range one can drive is 368 kilometres, which would equal a consumption of 86.4 kilometres per kilogram, according to the article.

I’m not so sure on the figures presented though and I think there has been a typo of sorts in it. Also note that the original article I first found on BenzInsider has disappeared again. However, having done a bit of maths, I’ll share this with you anyway.

 

As a given reference, the Nissan Leaf has a battery which is 24kWh, providing 160km of electric range. Given that the B-Class would have a 35kWh battery, the full range on the battery would be even more than 160km, but for the sake of comparison, let’s use 160km first and see how things go.

 

Option A First off, the full range of 368km and not using the battery. This would mean 3.7kg of hydrogen to be used for the total distance, would mean 99km/kg. That is more than what is stated, so there must be some battery power involved.

Option B The total range is said to be 368km. Subtracting the battery range of 160km, that leaves around 200km to be powered by the hydrogen fuel cell. 200km over 3.7kg equals around 54km/kg. Not the mentioned 86.4km/kg still.

 Option C Using the provided mileage as a starting point, 86.4km/kg, with 3.7kg would drive you for a distance of 319km. That leaves rougly a difference of 40-50km that is covered by a battery, that sounds more like other hybrids on the market. Comparing with the Prius for example, which has a battery in the order of 3.5 to 5kWh and results in almost 40km.

 

Conclusion Since the vehicle is a hybrid (a drive train consisting of a battery and a fuel cell), I would expect it to have a battery which is more in the range of 5-6kWh than the stated 35kWh. Moreoever, with a 35kWh the fuel cell would hardly be used at all, assuming the B-Class is also a plug-in. Not really helping to evaluate how a fuel cell would perform for normal drivers.

 

The lease price of the vehicle will be announced at the moment the B-Class is revealed and includes hydrogen fill ups. So regardless of what the actual figures of hydrogen consumption are for now, the people driving it would be (a bit) less concerned. I’m hoping that upon revealing the B-Class they would announce the actual price, but I’m more interested in the actual specs now to see what they went for. 

Drive Train – (Material) Efficiency

 

When talking about efficiency for (hybrid) electric vehicles, one often refers to the mileage of the car or the conversion of electric power to mechanical power. The efficiency I’d like to discuss here is material efficiency, as two nice (potential) breakthroughs popped into my reader this week.

 

The first is regarding the platinum use in fuel cells, where with a special mechanism it is possible to use less of this precious material to construct fuel cells. With the current share of car manufacturers promising us to deliver fuel cell powered vehicles in the near future, that will sure have an impact on those plans (and the price of such vehicles ofcourse!). The second is regarding a material called grapheme, a material of one atom-thick which can come in sheets and is expected to have a huge impact in the electronics industry. The problem with this material is that the discovery of it is quite recent (Nobel Prize in Physics was awarded this year to Andre Geim and Konstantin Novoselov for their groundbreaking experiments with this material. At the moment everybody is trying to find a commercially viable method to produce it and it seems good old sugar might do the trick.

The core of this technology, palladium with a platinum coating

For the construction of a fuel cell platinum is required to play the role of the catalyst in the reaction. The early models used quite a substantial amount of this precious material, making them hideously expensive. With the current breakthrough of the US Department of Energy (DoE) Brookhaven National Laboratory it is expected that ony about 10 grams will be needed for a fuel cell in a vehicle. Conveniently that is the same amount that is currently used in the catalytic convertor that is on ICE cars now, to treat the exhaust fumes. Effectively this means that a fuel cell vehicle and a conventional ICE vehicle requite the same amount of platinum to manufacture.

 

The key in this breakthrough is the use of palladium-gold cores which are then coated with the platinum. In a normal fuel cell over time the platinum dissolves, taking out the catalyst of the fuel cell which needs to be replaced. With the palladium-gold cores, the palladium gets dissolved first, while maintaining the catalytic ability of the platinum and ensuring a longer lifespan for the fuel cell.

Common sugar, the key to advanced electronics?

Graphene hit the news earlier this year when Andre Geim and Konstantin Novoselov were awarded the Nobel Price for Physics for their experiments on the material. Their famous method to construct the material by using scotch tape and applying it to graphite to scrape of small layers has popped up in many news articles. This method is not something that can be implemented on a commercial scale though, for that the researchers of Rice Research have found a way to produce graphene using common sugar. This is a super cheap material to produce such potentially high tech products with. It is expected that this discovery of graphene will lead to lighter electronics altogether and since modern vehicles tend to contain more electronics with every new model, this will surely help losing weight (and gain some miles in range).

Additional info:

Fuel Cell Breakthrough article

Graphene on article Cleantech

Graphene on Wikipedia

Nobel Price for Physics 2010