Hydrogen Cell - Fuel of the Future?

by Steve Auger
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Part 1:  This is the first post in a series on hydrogen fuel cells and their use in automobiles.  This post was originally published Sept 28.2008.

When it comes to next-generation vehicles, the hydrogen fuel cell is one of the most controversial topics.  The technology promises zero emissions (water vapor) and may potentially eliminate our dependence on fossil fuels.  There is an abundance of hydrogen and can be used far into the future.  BUT ... and this is a big BUT ... hydrogen is one of the least efficient fuel alternatives, the recurring production fuel cell cost will be high and the infrastructure will not available for years or perhaps decades.

What is a Hydrogen Fuel Cell?

A hydrogen fuel cell essentially produces the opposite of electrolysis.  Electrolysis separates hydrogen and oxygen from water by the application of electricity.  A hydrogen fuel cell requires hydrogen and oxygen as inputs and produces electricity and heat.  Some fuel cells can use air instead of oxygen as input.

The operation of a fuel cell is somewhat akin to a battery.  But a fuel cell does not require recharging so long as fuel (hydrogen and oxygen) is supplied.

Hydrogen Fuel Cell History

The hydrogen fuel cell can be traced as far back as 1839 when Sir William Robert Grove mixed oxygen and hydrogen and produced electricity and water, the opposite of electrolysis.  Although the experiment produced electricity, it wasn't enough to be useful.  It wasn't until the late 1950s that the fuel cell became a reality.  In 1959 Francis T Bacon demonstrated a 5KWatt fuel cell, known as the "Bacon Cell", and was capable of powering a welding machine.  The same year, Chalmers Manufacturing Co. demonstrated a 20hp tractor, the first vehicle ever powered by a fuel cell.

NASA got into the act in the 1960s.  Nuclear power was deemed to be too risky and batteries were too large and bulky.  Fuel cell technology seemed ideal for the Gemini and Apollo space capsules. General Electric was contracted to produce the hydrogen cell to fuel the electrical power system for these space vehicles.  The same fuel cells provided the drinking water for the crew.

Part II:  The next post will cover hydrogen cell theory, fuel cell applications and the different types available.

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Nuvi 255W: Green Technology?

Nuvi 255W:  Green Technology?

by Steve Auger

I recently decided to pack up the family and go for a week-long car trip to visit long lost family and hit some beaches.  Starting from Ottawa my wife and I drove to Toronto the first night.  I must explain that my wife isn't much of a fan of long car trips.  In fact she gets quite grumpy if we drive more than a couple of hours at a time.  So I was pushing my luck the first day with a 4+ hour drive.  

As luck would have it I got lost in Toronto.  I'm not sure how - I've driven this route several times before. but not for the last few years.  Perhaps with age my memory is failing a little, who knows?   In any case I managed to forget the turn-off from the highway for the hotel.  Driving an extra half hour through Toronto I got off on the wrong interchange and ultimately found my way to the wrong hotel.  I'm one of those men who hates to ask for directions, but since my wife was in the process of breaking my ear drum, I begrudgingly went into the (wrong) hotel and asked for directions for the right hotel.  By this point in time my wife was livid, screaming at me for not bringing the map of Toronto and just about every other mistake I've made over the 6 years of our marriage. 

After another half hour of driving I managed to find the correct hotel.   By this time my wife had decided I was going to go out early next morning and buy every road map available for Ontario cities and then some.  I tried to calmly explain that we already had all those maps but I simply forgot to bring them along.  In fact I couldn't quite understand why they weren't in the car already.  There is no use for them outside the car.  But this was to no avail.  Maps I must have if I wanted to survive married life for the coming week. 

At this point in time a green light went off in my head.  Why not invest in a GPS?  You know, one of those street pilots!  I'd never get lost again.  In fact, I could probably use it driving around Ottawa since my night vision isn't what it used to be.  It could probably save me driving time (and embarrassment) driving around my home city as well as when travelling.

So I decided to call my brother.  Being a GPS fanatic, he basically told me to only consider Garmin and specifically the Nuvi 200 series.  Forget any other manufacturer.  The Nuvi 255W is currently selling for approximately $215 CDN.  SO I promptly went down to a local electronics shop and bought one.  I came back to the hotel and told my wife I had solved my driving problems.   No more getting lost!  In fact she would never again be able to blame me for getting lost or taking the wrong route!

Anyways, to make a long story short - I've been using the Nuvi for the last couple of weeks.  My marriage is still intact as my wife can't blame me for taking the wrong road!  Below are my thoughts on the Nuvi GPS:

• Works well navigating through established (older) neighborhoods;
• The supplied electronic maps are out of date for the last year or two.  New streets are not recognized.  Admittedly I have not taken Garmin up on one free map download yet so this may solve my problems;
• The directions provided may not be the most efficient;
• Sometimes directs the driver into construction zones;
• You will never get lost provided you entered the correct destination!

So how does the Nuvi 255W stack up as green technology?

In certain situations the Nuvi will prevent you from generating significant amounts of greenhouse gases i.e. you will never drive that extra hour while lost and trying to find your destination.  Additionally, there are fewer driving distractions such as trying to read street signs or interpret a map.  These distractions not only cause extra fuel use (i.e. due to erratic driving) but can lead to car accidents. 

On the flip side, if you know where you are going or have an experienced navigator at your side then you can generally do better than the Nuvi.  My advice is to use the Nuvi as a companion when in unfamiliar territory.  Otherwise turn it off.

There is a feature I haven't had a chance to use yet called "Eco-Route".  The Nuvi allows you to enter your car's urban and rural fuel economy.  The Nuvi will ultimately assess your driving habits (for fuel efficiency) and generate reports.  The idea is to train the driver to drive in a more fuel efficient manner.

Here are a few suggestions for Garmin if they should ever tune into Blog On Smog:

• Provide proper specifications:  i.e. power use (Watts),  I could not find any specs on their website or user's manual.
• Go into hibernation when the driver will be on the same road for a long period of time.  After all there is no need to keep the display running.
• Make it easier to turn off when not being used. 

Should the the Nuvi really be considered green technology?  I'm not sure but I'm keeping mine.   My marriage can't afford to be without it :)

Pyrolysis is an Emerging Green Technology

Pyrolysis is an Emerging Green Technology

Author: Steve Evans

Pyrolysis is an emerging technology and its green credentials when the feed is biomass are top notch. Everyone who has lit a wood or coal fire and watched it burn has seen pyrolysis. Pyrolysis is usually the first chemical reaction that occurs in the burning of many solid organic fuels, like wood, cloth, and paper, and also of some kinds of plastic.

In a wood fire, the visible flames are not due to combustion of the wood itself, but rather of the gases released by its pyrolysis; whereas the flame-less burning of embers is the combustion of the solid residue (charcoal) left behind by it.

Although the basic concepts of the process have been validated, the performance data for an emerging technology have not been evaluated according to methods approved by EPA and adhering to EPA quality assurance/quality control standards.

Waste is converted to a fuel by heating the waste which burns just as coal or wood does under the right controlled conditions. Whereas incineration fully converts the input waste into energy and ash, these processes limit the conversion so that combustion does not take place directly.

Waste Plastic under pressure and catalytic cracking produces fuel and can be used as a fuel source. Under certain temperature conditions the plastic macromolecular chains are broken down into small molecular chains (simple hydrocarbon compounds) and those small molecular compounds contain C4 to C20, this compound is a component of petrol, coal oil, and diesel.

Anhydrous pyrolysis can also be used to produce liquid fuel similar to diesel from solid biomass.

Fast pyrolysis occurs in a time of a few seconds or less. Therefore, not only chemical reaction kinetics but also heat and mass transfer processes, as well as phase transition phenomena, play important roles. Fast pyrolysis is a process in which organic materials are rapidly heated to 450 - 600 degrees C in absence of air. Under these conditions, organic vapors, permanent gases and charcoal are produced.

Researchers at Virginia Tech have identified pyrolysis as a potential technology for disposing of poultry litter. The ultimate goal of the project is to develop transportable pyrolysis units to process the waste from poultry growers within one locality, thus reducing transportation cost. Researchers believe that the char, an inert and highly porous material, plays a key role in helping soil retain water and nutrients, and in sustaining microorganisms that maintain soil fertility. Researchers have obtained from wood - initially beech and then coniferous species - oils with almost ideal characteristics. Straw, which has a lower energy yield - 50% as opposed to 70% for wood - is also due to be analysed in the near future.

Bill Gates’ personal investment vehicle, is reportedly backing Sapphire Energy, a start up working towards a commercial-scale facility to produce oil from algae, but we think he would do well to look at gasification and pyrolysis as his energy technology because there are so many possibilities in this technology.

Gasification technology also offers the possibility to create a new domestic supply of gas. It works by converting the hydrocarbons in coal, biomass and waste petroleum products into a gas called "syngas" that can be used in place of natural gas to generate power, or used in manufacturing as fuel or feedstock. Gasification avoids many problems which can occur in biogas digesters, and is also able to process lignin and cellulose, which are hard to ferment.

Article Source: http://www.articlesbase.com/science-articles/pyrolysis-is-an-emerging-green-technology-744974.html

About the Author:

Steve Evans is enthusiastic about gasification and other renewable energy sources like anaerobic digestion plants. He also runs a great web site about the biogas.