is a very unusual gas
Actually 75% of the observable universe is hydrogen, but unless we're going to fuse
it into Helium.
Calling the Hydrogen Fuel Cell Industry our competitor,
is a little like saying Kodak competes with Paramount, one makes film the other makes movies. Ok so
maybe it's not the best analogy in the world, but it's better than the National Arbor Society and Charmin
A fuel cell installation is more closer to a diesel genset than
a PV array or a wind farm. That's not a bad thing, FC are quiet, efficient, and provide power on
demand; they are not inexpensive.
This little essay is mostly about how STS and fuel cells can cooperate in the future to provide clean power
for transportation; and inexpensive, reliable, solar-fueled combined heat & power. When we team up,
It takes 8kg of Oxygen to burn 1kg Hydrogen to form 9kg of Water.
On Earth Hydrogen comes from 4 sources.
- Reformation of Hydrocarbons & Carbohydrates.
- Disassociation of Water by thermal, chemical or electrical energy.
- Action of acids on metals.
- Hydrogen producing bacteria (Hmmm...)
#1 is the most common way that most fuel cells get their H2 today. What does that say for fuel-cells as
an energy source? They're just another engine, no that's not fair. But, since H2 isn't something
that's readily available as a source of energy, it's really just transport of energy, 'nuf said.
#2 is attractive because it looks circular. We've all heard that FC used H2 to make H2O, and H2O can be
recycled back into H2 & O2. Nice and clean and tidy. But where does the energy come from?
If is comes from burning coal or oi, then it's no bargain. Let's imagine that we have an in expensive
source of solar electricity to make H2... Now you're thinking!
#3 yes, this it how it's done in the lab, ah ha! Reactive metals, as a storage media of energy is in
our near future. Have you heard that Aluminum production has been down since the price of oil and
electricity has risen? Because it's been more profitable to sell the electricity rather than produce more
AL metal. Most aluminum refineries are located near big hydroelectric dams, they use a lot of electricity.
#4 if nothing else you might be able to claim that this is the "something new you've learned
today". H2 producing bacteria, digest biomass. They may be slow, but they reproduce, and they
could keep garbage out of the landfills. Perhaps we could help them out by supplying STS generators for
the facilities. We know, it takes electricity to run the pumps, filters, conveyors, etc. Then they
can sell the H2 as produce rather than burn it up locally.
We're not anti fuel cell, no more that we're anti photovoltaic. We just need to point out the
advantages of STS over those two technologies. In the long run, fuel cells will displace more and more of
the internal combustion fleet that uses so much foreign oil every day, but that'll take time.
Let's look at some of the pros & cons of fuel cells in general.
- Fuel cells are deviously simple, and notoriously difficult.
- A fuel cell is a pair of battery electrodes that don't consume themselves.
- Reactants enter the cell.
- Byproducts and heat leave the cell.
- Direct current is produced.
- Expensive $5-10/W
- High Fuel Costs
- Delicate (reactant purity)
- Short Lifetime
- High Maintenance Cost
What this means is that fuel cells serve specialized purposes. The one everybody should be familiar
with is the space program. When Apollo 13 had its mishap, what they lost was the reactants for the fuel
cells, oxygen, and hydrogen, and with it their only source of fresh drinking water. They still had
batteries, but not nearly enough to supply heat, light, computer, navigation, water... watch the movie.
Since then, fuel cells have found some new work, running things like municipal busses, and providing
emergency standby power for some critical applications. Despite high costs, the high efficiency of fuel
cells has spurred development. Another propulsive force is the good press they generate. Who could
forget Governor Schwarzenegger fueling up with compressed hydrogen at that press event? But seriously,
fuel cells are in our future.
The only problem we at Solar & Thermal Systems, have with the hydrogen economy as presented
in the popular media is the misconception that it represents a supply of energy. Hydrogen,
like batteries represents a storage of energy. So as I was taught, when you see a problem,
try to identify a solution. We've got a solution. If the high cost of the energy that feeds a fuel
cell is a problem, find a lower cost alternative... Solar & Thermal electricity costs $0.86/kWHr for 20
years. We'll leave it to the chemists to come up with the best conversion of electricity to hydrogen by
disassociating some chemical (water).
It's true that the cheapest source of hydrogen is currently the catalytic reforming of hydrocarbons, coal,
oxygen and water. Back in the late 1800's they called it illuminating gas, coal gas, producer gas, water
gas, etc... The only problem with this technique is that it does nothing to reduce carbon emissions, it
does get the emissions off the roadway, but concentrated them at a smokestack instead.
So again, just like photovoltaic energy, if fuel cells are put against Solar & Thermal Systems as a
primary energy source, we win, hands down. But if the STS technology can be paired with fuel cells, by
combining the advantages of each, then it's a win-win. Don't expect to see an STS powering a city
bus (or a moon buggy) anytime soon, but imagine Gov Schwarzenegger pushing the nozzle into his car as the camera
pulls back revealing a field of Solar & Thermal panels as the narrator explains how clean sunshine, makes
clean hydrogen, and just like the astronauts did, you can drink the exhaust from the tailpipe.