The Easy Way 2 Capture Hydrogen for Fuel

Javier Zarracina

This company may have solved one of the hardest problems in clean energy

The "hydrogen economy" may be a thing after all.

By Feb 16, 2018, 9:00am EST

It is an odd twist of chemistry that there is fuel embedded in the most common substance on earth: water.

Hydrogen — the H of H2O fame — turns out to be something of an all-purpose element, a Swiss Army knife for energy. It can be produced without greenhouse gases. It is highly flammable, so it can be used as a combustion fuel. It can be fed into a fuel cell to produce electricity directly, without combustion, through an electrochemical process.

It can be stored and distributed as a gas or a liquid. It can be combined with CO2 (and/or nitrogen and other gases) to create other useful fuels like methane or ammonia. It can be used as a chemical input in a range of industrial processes, helping to make fertilizers, plastics, or pharmaceuticals.

It is quite handy.

And it is the most abundant chemical element in the universe, so you'd think we'd have all we need. Sadly, it's not that easy.

It is expensive, in both money and energy, to pry hydrogen loose from other elements, store it, and convert it back to useful energy. The value we get out of it has never quite justified what we invest in producing it. It is one of those technologies that seems perpetually on the verge of a breakthrough, but never quite there.

Seattle native Evan Johnson thinks he can change that. He thinks he's finally figured out how to unlock a hydrogen economy.

Johnson is far from the first or only person with that goal. But after 10 years of tinkering, testing, and preparation, he has worked out a series of technologies and a practical business plan that chart a path to real commercial scale for hydrogen.

And though HyTech Power, where Johnson serves as CTO, obviously seeks financial success, Johnson sees its products as something more: a way to use hydrogen to immediately reduce pollution while scaling up and driving down costs enough to enable more fundamental changes to the energy system.

A stationary diesel generator with HyTech's hydrogen injectors installed.

HyTech Power

HyTech is targeting a big market to get to an even bigger one

HyTech Power, based in Redmond, Washington, intends to introduce three products over the next year or two.

The first will use hydrogen to clean up existing diesel engines, increasing their fuel efficiency by a third and eliminating over half their air pollution, with an average nine-month payback, the company says. That's a potentially enormous market with plenty of existing demand, which HyTech hopes will capitalize its second product, a retrofit that will transform any internal combustion vehicle into a zero-emissions vehicle (ZEV) by enabling it to run on pure hydrogen. That will primarily be targeted at large fleets.

And that will tee up the third product — the one Johnson's had his eye on from the beginning, the one that could revolutionize and decentralize the energy system — a stationary energy-storage product meant to compete with, and eventually outcompete, big batteries like Tesla's Powerwall.

At least, that's the plan.

The energy world is full of big-talking startups, of course, and the road from prototype to market success is long and perilous. HyTech will need much more than clever technology to succeed. It will need good execution.

To that end, it has recently attracted the backing of several seasoned Boeing executives, including Jerry Allyne, who spent 30 years at Boeing and came out of semi-retirement in December to lead HyTech's scale-up as COO.

Soft-spoken and deliberate, with a neatly trimmed beard, Allyne occupies a small second-floor office in HyTech's beige building, which is mostly taken up by a cavernous garage/workshop. "I was very skeptical of the technology, as I generally am," he says, but "once I could see it for myself and understand the physics, I thought, oh my gosh. This is really interesting!"

What drew him in is that the initial products require no new markets or infrastructure. "They can really change the world now," he says. The key is going after diesel engines first. There are millions of them, they are dirty and expensive, and policymakers are pushing to clean them up. That's a lot of demand. The company "expects to make a lot of mistakes," Allyne says, but the potential market is almost unfathomably large.

Working in the HyTech garage, retrofitting big diesel trucks.

HyTech Power

And the stakes could not be higher. It has become clear in recent years that some kind of zero-carbon, storable, combustible fuel is, if not essential to total decarbonization of the energy system, at the very least extremely helpful.

Before diving into HyTech's products, it's worth explaining why affordable hydrogen is such a tantalizing prospect for those concerned with sustainable energy.

The trouble with hydrogen: it's expensive to harvest, store, and convert it

About 95 percent of global hydrogen production is done through steam methane reforming (SMR), blasting natural gas with high-temperature, high-pressure steam. This is an energy-intensive process that requires fossil fuel inputs and leaves behind a waste stream of carbon dioxide, so it is of limited use for decarbonizing the energy system.

But it is also possible to pry hydrogen directly out of water via electrolysis — that's the process of zapping water (containing various "electrocatalysts") with electricity, stimulating a chemical reaction that splits hydrogen and oxygen. If electrolysis is run by zero-carbon renewable electricity, the resulting hydrogen is a zero-carbon fuel.

That solves the carbon problem, but there are others. The hydrogen in water doesn't really want to let go of the oxygen (they are "strongly bonded"), so cracking them apart takes quite a bit of energy. The resulting hydrogen has to be stored, either by compressing it as a gas with big pumps or by (weakly) bonding it to something else and storing it as a liquid. That gas or liquid will require a distribution infrastructure. Finally, the hydrogen has to be extracted from storage and converted back to energy, either by burning it or putting it through a fuel cell.

By that time, the amount of energy invested in the process exceeds what can be gotten back out by a wide margin.

That's been the barrier. When all the costs of the energy conversions are added up, "mining" hydrogen for use in a zero-carbon energy system has generally been a money-losing business. The useful services hydrogen provides cannot compensate for the energy (and money) it takes to produce and use it. At least not to date.

That's why, though people have been extracting and burning hydrogen since the 17th century, engines and fuel cells that run on hydrogen have been around since the 19th, and hydrogen has been through numerous hype cycles, right up through the 21st century, the much-heralded "hydrogen economy" has never quite taken off.

You don't see a lot of these around.

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As recently as the late 2000s, most energy experts had written hydrogen off. Two things have changed since then.

Affordable hydrogen could address the primary barriers to sustainable energy

The main thing that's changed is that a global clean-energy transition is underway. To address climate change, the world has effectively agreed to decarbonize the energy system entirely within the century. That has triggered intense investigation into the tools needed to build a zero-carbon system.

We know how to produce zero-carbon electricity (renewables, hydro, nuclear), so one key step in decarbonization is to "electrify everything," or at least as many energy uses as possible.

But large-scale electrification is a daunting task. There are lots and lots of existing applications that run on combustable liquid fuels. In addition to virtually all transportation, think of the millions and millions of buildings across the world heated by oil or natural gas.

Much transportation can be electrified, and all those furnaces can theoretically be replaced with electric alternatives like heat pumps, but doing all that in the time remaining to decarbonize is a truly monumental task.

It sure would be nice, to buy time if nothing else, if we had a zero-carbon liquid fuel we could just feed into those existing systems, to reduce the emissions of the vehicles and appliances we're already using. (The UK is experimenting with heating homes with hydrogen; Norway will ban all use of fuel oil for home heating by 2020.)

Also, if variable renewable energy (sun and wind) is to provide most or all of our energy, we will need some way to store that energy for when the sun and wind are falling short. We will need not just second-by-second or hourly storage (which batteries can plausibly provide), but daily, monthly, or yearly storage (for which batteries are not well-suited) to ensure against longer-term variations in sun and wind. It sure would be nice if we could store a lot of reserve energy as a stable, liquid fuel.

There is, in short, a hydrogen-shaped hole in our sustainable energy plans.

The second thing that's changed is that research, development, and early market testing have steadily reduced the cost and raised the durability of the basic components of hydrogen technology.

In sum, the need, combined with the innovation, may finally mean that market-viable products are at hand. That is why there is "a resurgence of hydrogen-based activity around the world," says Adam Weber, leader of the Energy Conversion Group at Lawrence Berkeley National Laboratory.

Or as Pierre-Etienne Franc, secretary of the trade group Hydrogen Council, recently put it, "the years 2020 to 2030 will be for hydrogen what the 1990s were for solar and wind."

Despite all the recent innovation, Johnson found again and again that every time he eschewed off-the-shelf components and built his own — virtually every element in HyTech's products is custom designed and built, with raw materials ordered off the internet — "the price went way down. I don't know why."

Johnson is tall, rangy, and blond, an inveterate maker and builder whose eyes light up when he talks engineering. After attending Seattle Pacific University, he spent the first 10 years of his 20-year career in video compression. But a stint in Norway, working with Innovation Norway on hydrogen energy storage, gave him the hydrogen bug. He has since become a true believer. "Betting the future on hydrogen is the best thing you could possibly do," he says.

"If the electrolysis is indeed that much cheaper, that is a game-changer"

It begins with the electrolyzer, which pulls the hydrogen out of the water. Johnson couldn't find one as cheap, simple, and efficient as he wanted, so he built his own.

A HyTech electrolyzer (in this case, attached to a stationary diesel generator).

HyTech Power

It's not much to look at, just a tube filled with distilled water. Suspended roughly in the center is a small titanium plate coated with a bespoke mix of electrocatalysts optimized to pull hydrogen and oxygen apart. The gases rise off the plate in a continuous stream of bubbles. It's all sealed in metal and there are no moving parts, so it is extremely durable and requires little maintenance.

Overall, Johnson says, the system is "very simple and dumb." (This is a theme he returns to frequently — a preference for closed-loop, simple, fully recyclable systems.) But thanks to the efficiency of the electrocatalysts, he adds, "it's very precise as far as how much energy is needed to produce the needed hydrogen."

Johnson boasts that his electrolyzer can produce hydrogen at about three or four times the rate of electrolyzers with similar footprints, using about a third the electrical current. That represents a stepwise drop in costs.

"Obviously I can't verify their economics from afar," James Brenner of Florida Institute of Technology's National Center for Hydrogen Research told me, "but if the electrolysis is indeed that much cheaper, that is a game-changer."

Now let's look at what HyTech plans to do with it.

Retrofittin'.

HyTech Power

A way to clean up diesel engines for a market that badly needs one

The first product, scheduled to debut in April, is the key to everything else.

It's called Internal Combustion Assistance (ICA), a modification to internal combustion engines that enables them to substantially increase their fuel efficiency and reduce their air pollution. It does this by adding tiny amounts of gaseous hydrogen and oxygen to the fuel just before it is combusted in the engine's cylinders. The HHO mix lends intensity to the combustion, allowing the fuel to burn more completely, generating more oomph and less pollution.

The ICA system can technically work on any internal combustion engine, but to begin with, HyTech is targeting the dirtiest engines with the fastest return on investment, namely diesel engines — in vehicles like trucks, delivery vans, buses, and forklifts, but also big, stationary diesel generators, which still provide backup (and even primary) power by the millions across the world.

All those diesel engines produce carcinogenic smoke containing particulate pollution (soot) and nitrogen oxides (NOx), which are hell on human health. States and cities around the world are cracking down on diesel air pollution.

But the diesel particulate filters (DPFs) that screen out particulates are expensive, a maintenance hassle, and must be replaced frequently. And the selective catalytic reduction (SCR) fluids added to exhaust to remove NOx are pollutants themselves and must be changed frequently.

In short, there are lots of diesel engines, they are very dirty (responsible for as much as 50 percent of urban air pollution in the winter), and there are lots of people spending lots of money trying to clean them up. That's a big market.

HyTech's offer to that market is pretty remarkable: it claims that its ICA can improve the fuel efficiency of a diesel engine between 20 and 30 percent, reduce particulate matter by 85 percent, and reduce NOx by between 50 and 90 percent. In concert with a DPF and some SCR, it can yield a diesel engine that meets official California standards for an "ultra-low emissions" vehicle.

The cost of transforming a dirty diesel engine to a relatively clean one: around $10,000 installed, which HyTech estimates will pay itself back in nine months through avoided fuel and maintenance costs.

HyTech's internal combustion assistance (ICA) product, installed on a large diesel engine. (See the little row of injectors?)

HyTech Power

HyTech is not the first or only company to develop an HHO additive system, but nothing on the market comes close to those kinds of numbers.

The ICA achieves this efficiency thanks to a computerized timing controller that senses and analyzes the turning of the crankshafts and camshafts to determine the precise timing and size of the HHO injection. Previous HHO systems more or less flooded the engine with HHO through the air intake, but HyTech uses "port injection," with a separate injector at the intake valve of each cylinder, controlled by the timer. Each injector (roughly the size of a human hair) squirts tiny, precisely measure jets of HHO into the cylinder just when it's needed.

This level of precision allows the ICA to use much less hydrogen than its competitors, much more efficiently. A small, onboard electrolyzer produces more than enough.

These are bold claims, but so far they've held up. The ICA has been listed by the EPA as a candidate for emissions-reduction technology; respected testing firm SGS found that the ICA boosted the fuel efficiency of a FedEx delivery truck by 27.4 percent; FedEx is currently road testing the ICA on a fleet of trucks and finding 20 to 30 percent better fuel economy and substantially reduced DPF maintenance costs. In third-party testing, and in limited local sales around Redmond, the ICA has performed as promised.

If it can do that as HyTech scales — reliably boost fuel economy by a third and reduce pollution to almost nothing, with a nine-month payback — there's no end to the opportunities. Between drayage (port) trucks, freight ships, refrigerator trailers, long-haul trucks, buses, generators, and all the other dirty diesel engines out there, the company estimates that clean-up is a $100 billion market.

The ICA doesn't rely on any new infrastructure or subsidies. It's a way to tap into a big market, reduce emissions immediately, and accumulate funding for longer-term efforts to replace diesel entirely.

HyTech also wants to clean up existing cars

Later this year, HyTech will introduce its second product line: pure hydrogen retrofits for ICE vehicles. Put more simply, it will take any engine that runs on diesel, gasoline, propane, or CNG and switch it over to run on 100 percent hydrogen. (The company is currently in the process of getting its retrofit product certified by the California Air Resources Board as zero-emissions.) This would allow any driver to get a zero-emissions vehicle for substantially less than the cost of buying a new electric or hydrogen fuel cell vehicle.

Johnson acknowledges that, if he were designing a vehicle from scratch, he would design it around a hydrogen fuel cell with no combustion, but "we have no interest in becoming a car company," he says. Instead, HyTech wants to clean up existing vehicles.

Not everyone can afford a Toyota Mirai hydrogen fuel cell vehicle (starting at, ahem, $58,365).

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For a pure-hydrogen (as opposed to mixed HHO) application like this, the electrolyzer is slightly different. The hydrogen is passed through a membrane that strips it of any remaining oxygen or nitrogen, leaving pure hydrogen for the vehicle to burn. (That makes the electrolyzer a proton exchange membrane, or PEM, electrolyzer, a variant familiar to hydrogen fans.)

As is his wont, Johnson designed his own membrane, remixing raw materials to create something more efficient and cheaper than other PEM products on the market.

There's another difference too, which represents one more of Johnson's core tech developments.

The power demands of a vehicle engine are variable and can ramp up and down quickly, so the system needs to keep a bit of hydrogen stored as a buffer, in case it draws more than the electrolyzer can produce.

Conventional hydrogen fuel cell vehicles (like the Toyota Mirai) store their hydrogen as a highly compressed gas, at about 8,000 psi. But compressed gas introduces all kinds of issues. It takes a lot of energy to compress the gas, it requires its own dedicated infrastructure, compressed-gas fueling stations are wildly expensive to build, and compressed hydrogen is, well, explosive, so every tank full of it is a potential bomb.

Johnson wants nothing to do with that. So he's taken another route. His system stores hydrogen, weakly bonded to metals as "hydrides," in an inert, non-pressurized (~200 psi) liquid solution.

The challenge with hydrides has been twofold: a) creating a bond weak enough to be broken without undue energy when the hydrogen needs to be released, and b) increasing the energy density of the resulting fluid. (To date, most hydride fluids have been less energy dense than compressed hydrogen, and far short of fossil fuels. They weigh too much for the energy they provide.)

Johnson thinks he's cracked both problems. He won't reveal the details of the hydrides involved, but he's got the power-to-weight ratio high enough to beat lithium-ion batteries (which are very heavy) and the hydride bond weak enough that it can be broken using only the redirected waste heat from the engine (no added heat or pressure required).

What's more, he's been working with a team on nano-materials for hydrides and expects a "massive leapfrog" in power-to-weight in coming years; eventually, he says, he wants energy density competitive with fossil fuels.

Efficient electrolysis plus efficient hydride storage means that Hy-Tech's retrofit will produce a zero-emissions vehicle (ZEV) with an average of 300 miles range, comparable to high-end electric vehicles but able to work in any existing vehicle. When I toured HyTech's Redmond facility, Johnson drove me to lunch in a giant Ford Raptor pickup truck running on hydrogen.

A Ford Raptor, running on pure hydrogen.

HyTech Power

There are two ways to "fill up" the vehicle. The slow way is to plug it in overnight, providing power for the electrolyzer to fill the tank. The fast way is to fill it up with hydride solution, which could be generated on site, either at home or a filling station, with nothing but an electrolyzer, some distilled water, and a tank.

No infrastructure yet exists to support such fast refueling, but it isn't like high-pressure compressed hydrogen, Johnson stresses. It's not dangerous; it produces no toxic byproducts; it doesn't require a bunch of government safety rules and enforcement; in theory, mom-and-pop gas stations could get a pump running pretty cheaply.

Johnson's somewhat utopian vision is that eventually every home and business will have an electrolyzer and a full tank of bonded hydrogen, which could be used either to generate electricity for the building (more on that in phase three) or to fuel hydrogen vehicles.

Leaving behind internal combustion engines is the goal, Johnson says, but "it's like quitting smoking — everybody wants to go cold turkey. It's just not going to happen." Retrofitting existing vehicles, for a fraction of the cost of a new zero-emission vehicle, will enable the company to begin reducing transportation emissions quickly.

HyTech's holy grail: long-term, affordable energy storage

Finally, funded and capitalized by its retrofit products, HyTech will launch into energy storage. Its Scaleable Energy Storage (SES) product is meant to compete with big batteries like Tesla's Powerwall, either as on-site storage for homes and businesses or as grid-scale storage attached to large solar and wind farms.

The vision behind hydrogen energy storage is that, someday soon, there will be regular periods when wind and solar are generating electricity well in excess of demand. That surplus energy will be dirt cheap — in fact, we'll be looking for ways not to waste it.

One increasingly popular idea is "power to gas," i.e., converting that surplus energy to hydrogen and storing it. "Hydrogen is probably the simplest thing you can make when electricity prices are depressed," says Weber.

Some of that hydrogen could be injected into existing natural gas pipelines, reducing the carbon intensity of gas. Some could be combined with carbon dioxide to create other liquid fuels. And some of it could be converted directly back to energy with fuel cells. "Stationary storage is a wonderful potential opportunity for hydrogen fuel cells," says Levi Thompson, director of the University of Michigan's Hydrogen Energy Technology Laboratory.

The problem, once again, has been that the end-to-end efficiency of electrolysis-based hydrogen energy storage has typically been less than half that achieved by a lithium ion battery.

Some bad stock art illustrating hydrogen energy storage.

Shutterstock

Once again, Johnson thinks he has cracked it.

Here's how HyTech's SES works: Power comes in (from solar panels or wind turbines, ideally) to run the electrolyzer. The hydrogen produced either goes into a fuel cell (yes, Johnson built his own) or is bonded as hydrides and stored in a tank. When power is needed, the hydride bonds are broken using waste heat from the system, freeing more hydrogen for the fuel cell.

By avoiding compression and finding a hydride bond weak enough to be broken by waste heat, Johnson has markedly improved efficiency. He's improved efficiency further with another clever technique. Most hydrogen storage uses huge electrolyzers and fuel cells, which cannot precisely scale energy production to demand. Johnson modularized his system: it contains stacks of smaller electrolyzers and fuel cells, which can be brought online one at a time as demand increases. "Stupid simple," he says with a smile.

From the outside, the SES performs exactly like a big battery, but there are differences and tradeoffs.

On the downside, though he has substantially increased end-to-end efficiency relative to hydrogen competitors, Johnson still hasn't quite matched the efficiency of batteries. He says the SES is about 80 percent efficient at this point. At least when they are new, traditional lead-acid batteries are around 90 percent and lithium-ion batteries are around 98 percent or higher, though all batteries degrade over time. (Johnson expects SES efficiency to continue rising as he develops new materials for his electrolyzers and fuel cells — he thinks 85 or 90 percent is within reach.)

On the upside(s), the SES will last much longer than a battery, through more than 10,000 charge-and-discharge cycles, relative to around 1,000 for a li-ion battery. That would make its lifespan closer to the lifespan of a typical solar panel, allowing the two to be more conveniently paired.

Unlike batteries, which cannot be fully charged or discharged for fear of degradation, the SES can go from 100 percent capacity to 0 and back without damage.

And when it does wear out, unlike batteries, the SES is entirely recyclable. The metals are melted down, reground, and reused; the water is redistilled.

Best of all, a hydride solution can be stored indefinitely without maintenance or loss of potential. It doesn't need to be pressurized or cooled like compressed hydrogen. It doesn't degrade like electrochemical charge in batteries. Hydrides can be stored for as long as necessary.

That makes the SES a fantastic candidate for long-term energy storage, the holy grail of a truly sustainable energy system. If the electricity feeding in were cheap and abundant enough, there is in principle no limit to the amount of reserve energy that could be stockpiled.

It also makes the SES perfectly suited to a distributed energy system. With no moving parts, durable components resistant to temperature and weather extremes, and 98 percent recyclability, it would be a dead-simple way for anyone with some solar panels to gain a degree of energy independence. It could be a particular boon to remote, off-grid communities.

The electrolyzer, spookily lit.

HyTech Power

Whatever HyTech's fate, the need for hydrogen will elicit innovation

A distributed, carbon-free hydrogen economy is the kind of thing Johnson muses about when he allows himself time to muse. But these days, the task at hand is more immediate: get HyTech up and running.

None of the hydrogen experts I talked to found any particular red flags in HyTech's technical claims, but they all evinced a hard-won show-don't-tell skepticism. The hydrogen world has seen many a Next Big Thing come and go. History is littered with the corpses of promising startups that were not able to translate their innovations into viable market products.

Nonetheless, Hytech seems well-positioned, with a credible leadership team, some early funding, positive results in testing, partnerships with big players like FedEx and Caterpillar, and a target market with demonstrated demand for its product. We'll likely know in a year or two whether they pulled it off.

Either way, as momentum toward a sustainable energy system builds in earnest, the need for hydrogen will only grow more acute. We need zero-carbon fuels and we need long-term energy storage. Hydrogen fits both bills.

When there is great social need and money to be made, people get clever. If Johnson can work out several stepwise advances in hydrogen technology by shopping online and tinkering in his lab, it won't be long before others do the same. And as products reach market, scale will bring costs down, just as it has for wind and solar power.

In many ways, affordable hydrogen is the final piece of the sustainable-energy puzzle, an energy carrier that can fill in the cracks in a system run primarily on wind and solar power. It has been left for dead several times over the years, but as the world gets serious about decarbonizing, hydrogen may finally win its day in the sun.

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Source: https://www.vox.com/energy-and-environment/2018/2/16/16926950/hydrogen-fuel-technology-economy-hytech-storage

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