Fuel Cell or not Fuel Cell? That is the question.

Fuel Cell or not Fuel Cell? That is the question.
by Richard Lewis

Everytime I see a news story either online or on the TV about hydrogen, they always seem to mention fuel cell technology. It's not that I hate fuel cell technology. It's just that there are so many problems as of current, that it isn't a suitable technology for the near future. Maybe in 10 years or so...who knows.

Cost
Let's take the average sedan with 100 horsepower and do some simple math. If you have 100 hp, then that is equal to 74,600 watts. A good internal combustion engine (ICE) runs at about 35% efficiency (average car is about 25%). So, that would mean that the car used 213 kw in fuel just to get its useable power. The average cost for a fuel cell is about $4,500/kilowatt. That would mean that a fuel cell for that average sedan would cost (at 50% eff.) a whopping $475,000! By the end of the decade they hope to be down to $800/kw. Even that would make for an expensive fuel cell costing about $85,000. If they ever make it to $35/kw by 2015 or so, then that would be $3700 per fuel cell.

And platinum is getting more rare and more expensive. There simply isn't enough platinum on the planet to supply all 800 million cars with fuel cells. And platinum will skyrocket in price if fuel cells become more mainstream. Alkaline fuel cells could be used, but they don't work well when carbon monoxide is present. And as a transitional phase to a hydrogen economy, there will still be "regular" cars on the road producing plenty of carbon monoxide. Also, the alkaline fuel cell is far too bulky for cars.

Efficiency
Everyone will tell you that fuel cells are more efficient than internal combustion engines. The fuel cell is often just above 50% efficient. While a typical internal combustion engine (ICE) is about 25%. But here is the rub. If you take a typical ICE and convert it to run off of 100% hydrogen, then you will have to change the timing to about top dead center. Then the efficiency will go up to about 50%. Less power is wasted in heat and less is transfered to the walls of the cylinder. In fact, most will be transfered to the downstroke of the piston. In reality, this efficiency boost isn't always seen as pure horsepower but rather a boost in fuel efficiency.

How long do they last?
Another problem is how long a fuel cell lasts. According to Perdue University, an ICE will last about 5,000 hours while a fuel cell will typically last about 1,000 hours. If you were to drive an hour to work and an hour home and a couple hours on the weekend, then that would be about 12 hours per week. That works out to just over a year and a half before your $100,000 fuel cell is dead. Yeah, that's a bargain. NOT

Pure Hydrogen
To put it simply, the hydrogen going into your $100,000 fuel cell has to be extremely pure. Otherwise, you might damage it.
Alternatives? Meet the ICE engine

Let's face it, switching over to hydrogen is a huge step. We don't really have the infrastructure set up. At $250,000 per fuel cell car, it doesn't seem likely that a large portion of the 800 million cars on the planet will switch over. I don't even see a large portion of wealthy people switching over, especially knowing that a $100,000 fuel cell has to be replaced every couple of years.

But there are some shortcuts we can take. For example, we could use natural gas pipelines to transfer hydrogen across the country. And depleted oil wells could be used as a temporary storage of excess hydrogen.

We could setup hydrogen generators at home that will turn electricity and water into hydrogen. They could also be run with solar and/or windmills.

And since most vehicles on the road these days use internal combustion engines, we could do a cheap conversion on them so they could utilize hydrogen and/or gas. The IC engine will last about twice as long running off straight hydrogen and will need fewer oil changes and tuneups. Imagine 10,000 hours of driving. In the above example, that would be 16 years of nice driving and only changing the oil and spark plugs a few times.

And the upgrade is simple and fairly fast. It involves a carbon fiber tank for storage, a header injection system and a few controls and valves. Something any mechanic can perform. A rough estimate today would be about $1,000 in parts...maybe $1,500. That sure beats a $250,000 car and a $100,000 fuel cell replacement every few years. The government could even offer tax breaks for having a conversion done.

A car properly modified to run off of hydrogen can actually clean the air. The only exhausts from this type of vehicle will be water vapor and a very small amount of nitrous oxides. Although, the nitrous oxides would be about 500 times less than a normal car emits. So, a hydrogen car driving around the city would actually clean the air.

And since you can still run off of regular gasoline, there is no downside. You can even run in hydrogen boost mode. This is when you run off of normal gas and add about 7% or more hydrogen to the mix. This will boost your fuel economy about 30%.

sources-------
http://news.uns.purdue.edu/html4ever/2005/050510.Agrawal.fuelcells.html
http://www.fossil.energy.gov/programs/powersystems/fuelcells/
http://www.bullnet.co.uk/shops/test/hydrogen.htm#cost
http://www.clean-air.org/
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Posted by Richard at 10:09 PM