It’s been described as the Holy Grail of alternative energy sources: The most widely abundant element in the universe that can be produced, stored, and transported anywhere on earth. When used to produce electric power with fuel-cell technology, its only byproduct is water, eliminating the carbon and other pollutants produced by burning fossil fuels. Now, backed by increases in private and government funding, the pace of hydrogen research and development is picking up speed.
But there’s a catch. Despite the recent urgency to develop hydrogen as an energy source — driven by rising oil and natural gas prices and concerns about global warming — a number of major scientific and engineering hurdles remain before this wonder fuel can compete economically with fossil fuels. Even its strongest proponents concede it may be decades — if ever — before hydrogen fulfills the promise of providing a clean, renewable source of energy to power the coming century.
When President Bush pulled up to one of the first U.S. hydrogen filling stations earlier this year, the photo-op message was clear: The Hydrogen Economy is coming. To support the White House’s hydrogen ambitions, this year’s hard-fought energy bill boosted funding for hydrogen research and development by nearly $2 billion over the next five years, authorized another $1.3 million for demonstration projects and added tax incentives for customers who buy hydrogen fuel cells. At the center of this effort is the government’s FreedomCar project, a partnership that includes the Department of Energy, auto makers, energy producers and others working to develop a commercially-viable car powered by hydrogen.
The latest round of government funding comes on top of billions already spent by vehicle manufacturers, fuel cell makers, energy producers, university researchers and others around the world to accelerate the replacement of fossil fuels with hydrogen.
General Motors recently set one of the most aggressive targets: To build a hydrogen fuel cell vehicle by 2010 that can compete economically with conventional gasoline-powered car. It’s a huge bet. So far, the company has invested $1 billion in the program and will probably have to spend another $1 billion to pull it off, according to Larry Burns, who heads the project as GM’s vice president of Research and Development.
“One of the reasons we embarked on this pathway was to find out whether it’s possible or not,” said Burns. “And so far, we believe it’s possible.”
But even some of hydrogen’s most enthusiastic proponents say it will be quite some time before you pull up to a pump and say “fill ‘er up with hydrogen.” An influential report last year by the National Research Council, in calling for additional funding for hydrogen research, warned that “success is not certain.” Some skeptics argue that, despite the billions being invested, there are simply too many fundamental scientific breakthroughs that will have to happen before a commercially viable hydrogen car can be produced.
On top of the list of hydrogen hurdles is the problem of developing onboard storage for a fuel cell car. Gasoline is very hard to beat as a transportation fuel. It’s very dense, packing a lot of energy in a small space, and it’s stable at normal air pressure and a wide range of temperatures. You can ship it long distances in large quantities via pipeline and dispense it safely at filling stations to consumers with no special training in handling volatile materials.
Hydrogen, on the other hand, is the lightest element on earth, which makes it very diffuse. To pack enough onboard a car, you need to compress and store it under extreme pressure or liquify it at extremely cold temperatures — both of which present daunting engineering and safety issues. Some researchers believe the solution may lie in storing the gas in a family of materials known as metal hydrides, which act something like a sponge, allowing you to charge up and release hydrogen as needed. But metal hydrides may prove to be to heavy. So far, no one has come up with a workable solution.
“If we can’t solve the problem with storage on the car, then that could kill the whole thing,” said Gene Nemanich, a Houston-based energy consultant and a member of NRC committee that wrote last year’s report.
Fuel cells 101
Then there is the challenge of making an affordable fuel cell to generate the electricity to power a hydrogen car. Though hydrogen can be used , much of the latest research and development effort is focused on fuels cells because they’re potentially twice as efficient in powering a car.
A fuel cell works something like a battery. Hydrogen atoms (which, if you skipped chemistry class, consist of one proton and one electron) are pumped across a catalyst like platinum, which strips off electrons that then flow through a membrane that holds back the protons. The electrons then go their merry way down a wire to power the car’s electric motors. When the electrons have finished their job, they reunite with the waiting protons, forming hydrogen atoms again. And those hydrogen atoms, the H in H2O, combine with oxygen to form water.
The problem is that, so far, no one has been able to figure out how to make a fuel cell anywhere close to cheap enough to power an affordable, mass-produced car. GM has set a target of $50 per kilowatt for each cell, a price point at least ten times cheaper than the cheapest fuel cells available today. Researchers haven’t yet found cheap enough materials, or figured out how to mass produce fuel cells cheaply enough.
Mass production usually brings rapid price cuts for hot-selling products like consumer electronic devices. But unlike “early adopters” of consumer electronics, few car buyers are willing to spend four or five times the eventual mass market price just to show off a new technology to their friends, according to Joseph Romm, a former Department of Energy senior official and author of ‘The Hype About Hydrogen.’
“You have this obstacle,” he said. “If we had huge amounts of (fuel cell) sales the cost might be lower. But we’ve got to get people to buy huge amounts before the price is lower. That problem was fatal to electric vehicles, and even for natural gas vehicles.”
It’s part of the so-called “chicken and egg” problem that is central to the challenge of moving from one transportation technology to the next. Beyond the hurdle of ramping up cheap mass production, hydrogen skeptics like Romm warn of another major Catch-22 facing the the rollout of fuel cell cars. Simply put: these cars will be a tough sell, he says, until consumers are convinced that hydrogen filling stations will be available wherever they want to go. But who will put up the billions — possibly trillions — of dollars required to build that distribution system until it’s clear there will eventually be enough hydrogen cars on the road to justify the investment?
“Essentially what you’re asking the Texacos and the Shells and Mobils is to make the following gamble: ‘You’re going to build this that at best is going to compete with an existing profitable product line of yours — gasoline — and at worst is going lose every last cent you put into it,” he said. “The investment makes no sense.”
One solution, say hydrogen researchers, could be to start with fleets of government or company cars fueled at a central location. Shell’s strategy envisions concentrating distribution on a regional level before rolling out hydrogen filling stations nationwide. Some have even suggested it would be cheaper and easier to deliver hydrogen by tanker truck directly to fuel cell cars instead of converting tens of thousands of filling stations to carry hydrogen.
The production puzzle
There’s also a major debate over just where all this hydrogen is going to come from. Like gasoline, hydrogen is what’s known as a “secondary” energy source: You have to make it from natural gas or water. Hydrogen manufacturing is already well established for industrial uses like gasoline refining and fertilizer production; about 50 million metric tons are made each year worldwide. (That’s enough to power “all the family cars in the U.S. if they were fuel cell vehicles,” according to Shell Hydrogen.)
But almost all of the hydrogen produced today is made from natural gas, a fossil fuel that is already in short supply and growing ever more costly. The process also leaves behind large quantities of carbon dioxide, which defeats one of the basic appeals of hydrogen power — eliminating pollution. Though researchers are working on a process called “carbon sequestion” — essentially pumping CO2 back into the ground where the natural gas came from — the process is not widely used. It’s also not clear how much impact the added cost of widespread disposal of CO2 would have on the economics of producing hydrogen.
A potentially cleaner way to make hydrogen involves a process called electrolysis, which is essentially reverses the fuel cell’s chemistry: This time, you run electricity through water, splitting H2O back into hydrogen and oxygen. But if that electricity is generated by burning fossil fuels, the pollution eliminated from a hydrogen car's tailpipe would simply be shifted to the power plant. So the promise of a clean hydrogen economy requires the use of renewable power sources like solar or wind power. Even the most optimistic projections say it will take decades before renewable power can produce more than a fraction of the hydrogen need to replace gasoline.
Major energy producers like BP and Shell say they’re trying to solve that problem by boosting production of renewable power. They’re also at work on another major challenge: How to distribute hydrogen to retail customers — if and when car makers eventually figure out how to produce an affordable fuel-cell vehicle. The Shell filling station President Bush visited in May was designed to show the public — and decision makers in Washington — the company’s idea of what a hydrogen station might look like.
The idea was “to demonstrate to people that a hydrogen pump would look like a regular gasoline pump,” said Phil Baxley, Shell Hydrogen’s vice president for business development. “It sits alongside the bays for diesel and gasoline, and we stored hydrogen underground like we store gasoline now.”
Baxley says the safety issues associated with transporting, storing and dispensing hydrogen to retail customers are not all that different than handling other gas fuels like propane. But it remains to be seen whether safety measures developed for industrial settings for workers trained in handling gas fuels can be adapted for a retail pumping station. The cost — and consumer acceptance — of these safety measures could pose another hurdle for hydrogen.
Despite its compelling advantages of as a clean, abundant replacement for fossil fuels, in the long run, the successful development of a “hydrogen economy” will be driven by economics. And so far, one of hydrogen’s most compelling advantages — the virtual elimination of pollution and carbon-based greenhouse gases — doesn’t by itself provide any direct economic benefits to energy producers or consumers. For that to happen, the U.S. and other large energy consumers like China and India would have to impose economic penalties for carbon emissions — or adopt a so-called “cap and trade” system of letting companies that exceed carbon caps buy permission to do so from companies that produce less than their share of emissions.
Hydrogen is also competing with other energy gasoline alternatives that could pay off sooner. So if oil and gas prices prices continue to rise, hydrogen could find itself pre-empted by other, cheaper forms of more readily available renewable fuels, including biodiesel or ethanol made from crops. Converting coal to liquid motor fuels could also become economically competitive. If battery technology improves more quickly than fuel cell breakthroughs, “pluggable hybrid” gas-electric vehicles could eventually evolve into all-electric cars that could store enough power to match the range of conventional gasoline-powered cars.
All of which has put added pressure on hydrogen proponents and backers to demonstrate that they can cross the finish line first.