|View Readers Comments about Fuel Cells|
There is nothing simple about fuel cells.
Oh, the concept is simple. A fuel cell is a battery that you can refuel. Period. End of story. They make electric current. They should have been called Fuel Batteries.
Fuel cells are batteries that can be fueled by gasoline, methane, ethanol, or hydrogen, to name some. Charge producing electrons are chemically extracted from the fuel by the elements inside the fuel cell, which from an electro-chemical standpoint are identical to the elements inside the common battery, a continuous electric current, with energy derived from this fuel input. They last anywhere from one to six years before they wear out or need an overhaul.
They come in all sizes, and will be used for everything from micro-appliances to tools and appliances, to home power units, to car power units, to building power units, to utility power plants. Fuel cells will power ships at sea and colonies in space.
Fuel cells today are expensive to manufacture and depend on ongoing technological innovations to ensure their eventual economic viability. For example, unless you want to run a fuel cell on hydrogen fuel, you will have to process your fuel through a “reformer.” This device reformulates non-hydrogen fuels such as gasoline, methane, etc., to turn them into hydrogen.
This problem is being overcome but progress is slow. Reformers are still very expensive. Some of the higher temperature fuel cells can actually directly process non-hydrogen fuels, methane, gasoline and ethanol, without using the reformer. This can degrade and destroy lower temperature fuel cells, as well as high-temperature fuel cells using earlier technologies. And high temperature fuel cells that can directly process non-hydrogen fuels are still expensive, too. Nothing simple here.
None-the-less, if technology stocks are overvalued, some fuel cell companies may be undervalued. Imagine when the next wave of consumer electronics hits. The next wave of portables will need something easier than batteries. Think of fuel cells vs. batteries the way you might think of digital stills vs. film stills. No reloading. No film container. Just add energy. The fuel cell subsystem lasts for the same lifetime as the whole unit. In the future, the fuel-cell powered VR headset or heads-up-display sunglasses will recharge by plugging a small fuel ampoule into a port on the unit. A pill of ethanol, for example. Standard size ampoules for all kinds. That’s pretty easy and pretty cheap electric power maintenance. Beats batteries. Gets my vote.
Cars using fuel cells still take a long time to start their engines, and since most car drivers take a quick start for granted, this is a problem. Energy density is also still a factor limiting automotive fuel cells, since a moderate size car on acceleration needs at least 100KW per kilogram. Fuel cells for cars that are economical to produce today are only getting about half that efficiency.
|Nissan Fuel Cell Car|
One of the biggest remaining questions with car fuel cells is what fuel will they use? The chief advantages of methanol is that it is for all practical purposes limitless in supply, insofar as methanol can be derived from natural gas, whose proven reserves worldwide are easily quintuple that of oil. Also advantageous is that methanol is distributed in liquid form, which means that methanol can use the existing distribution network in place for gasoline. Even underground tanks that held gasoline can be easily converted to hold methane.
Hydrogen as a fuel is championed because, theoretically, it can be derived from totally renewable sources, such as solar energy. Hydrogen, moreover, creates absolutely no air pollution when it burns. Finally, hydrogen fuel is the optimal fuel to use in a fuel cell since it will cause the slowest degradation of the elements of the fuel cell. The disadvantages of hydrogen are that it must be transported and stored under extreme pressure, up to 2,000 PSI. Two somewhat related consequences of this are an entire new distribution and storage infrastructure must be built, an undertaking of massive, nearly incalculable expense, and since hydrogen is highly flammable, an explosive hazard is created and an infrastructure must be created to counter and prepare against.
In reality fuel cell powered cars will eventually be built using all fuels. Some will be hybrids using combustion engines. Some will use fuel cells that tolerate various fuels. Some will use hydrogen generated and stored by the personal home fuel cell power units of the car owners. What fuel will prevail for cars using fuel cells? Don’t bet against gasoline. Don’t be surprised if several fuels occupy niches in the car market, either.
For homes and buildings fuel cells are already here. Check out the General Electric “HomeGen 7000″ fuel cell home powerplant (www.gepower.com/microgen/homegen_prod_desc.html). About the size of a refrigerator, less expensive per month than your utility bill, runs on propane! For buildings and for utilities, fuel cell powerplants are beginning to make economic sense. The potential for home and commercial building power systems using fuel cells, particularly in the United States as utility deregulation rolls out through the states, is probably much higher in the short run than that for automobiles. The heat produced by fuel cells, which is a liability in an automobile, is used for thermal co-generation in home power systems and is an asset. In the automotive market fuel cells are in competition with smart new hybrid vehicles and combustion engines that are themselves undergoing massive increases in efficiencies. By contrast in the utilities market fuel cells are competing with an under powered energy infrastructure and imminent percentage energy price increases in the triple-digits.
Fuel cells have been around a long time, over 100 years, but the materials cost along with the complex manufacturing process has limited development. New concerns about air quality as well as the availability of petroleum-based fuels has spurred their recent development. Their adoption around the world is inevitable, because of the convenience and independence they will give power consumers, as well as their ecological benefits, and, at last, their technological and economic viability. But they will not proliferate overnight, and where they show up first will surprise a lot of people.
It would be ironic if the first place we see fuel cells
widely used is to power consumer electronic portables and micro-devices, where their convenience outweighs any cost considerations, and the global energy and ecological impact of their adoption is negligible.
The next place fuel cells are likely to be widely adopted will not be in cars, but in home power systems. The ongoing cost of fuel and maintenance for a home power unit that uses a fuel cell is about the same as the average utility bill. This is going to change dramatically in the wake of utility deregulation and home power units using fuel cells will become a compelling investment overnight. Don’t forget their purchase may be subsidized for the homeowner or commercial building owner in the form of tax incentives, to boot.
Further irony might be found in the likely fact that the last place we’ll see widespread adoption of fuel cells will be onboard automobiles, since it is regarding tomorrow’s cars that we’ve all heard about fuel cells. Or in the likely fact that when and if these fuel cell powered (and hybridized with an internal combustion engine) electric autos do hit the road, most of them will run on ordinary gasoline.
EMAIL TO THE EDITOR
From: ALAN DIKA
Sent: Thursday, February 20, 2003 5:13 AM
Subject: fuel cells
Emailer: How much energy does it take to make a fuel cell?
Editor: We don’t know, but what you refer to is embodied energy, i.e., the total BTU’s (or equivalents) necessary to manufacture a fuel cell. “Renewable” energy, or any type of energy, cannot be evaluated solely on the energy output vs. energy input ratio during its useful life. The ultimate positive relationship between energy input and energy output with an energy device must take into account not only net BTU’s produced during the device’s useful life, but also the quantity of BTU’s expended to make the device. Also remember that a fuel cell doesn’t “make” anything, it is a conversion device; in the case of a fuel cell, hydrogen is converted to electricity.
Emailer: How much energy does it take to reform products to become useable hydrogen?
Editor’s reply: Again you are talking about devices that have some amount of “embodied” energy, which must be included in the efficiency calculation of any energy conversion or energy generating device. Fuel cells depend on hydrogen, which either must be reformed (refined) from fossil fuels, or extracted from water using electricity.
Emailer: Do we really reduce pollution, or do we move the source from the tail pipe to the coal burning power plant and natural gas burning manufacturing facility?
Editor’s reply: In the case of electric motor vehicles that use hydrogen fuel cells (or batteries or hybrids that use fossil fuel driven electric generators, for that matter), they are only moving the source of the pollution, not necessarily reducing pollution. Even vehicles powered solely by on-board photovoltaic cells to produce electricity would only be moving the source of their pollution, since photovoltaics must themselves be manufactured, and hence have embodied energy that requires its own generation. The idea of totally pollution-free energy is a myth.
Emailer: I’m all for fuel cells if they ultimately do less harm to the environment than the alternatives. I just haven’t heard any arguments about the issue, so I’m hoping you can point me to a source.
Editor’s reply: It is our goal with EcoWorld is to post credible quantitative information as to the ultimate efficiency of energy alternatives. We are hopeful you might point us to a source.
Emailer: It really seems that reducing consumption is the best way to save our planet- unlikely as that might be.
Editor’s reply: EcoWorld would posit that improving efficiency, via whatever method of energy production, in a pollution-free process is enough. Improving efficiency is better than reducing consumption, and equally feasible, we would say.