GH

Greg Heller · Hydrogen · Houston

Follow one molecule from water to wheels.

The white CHRS refueling cabinet with its gauge window and nozzle holster
The CHRS cabinet, Houston, 2023. A 5 kg/day prototype that refueled a Toyota Mirai.

I spent 2018 to 2025 at HNO International building hydrogen small and scrappy: borrowed lab space, tiny teams. I was CTO, then stepped back to technical advisor so I could help build what came next. Since Aug 2023 I've helped develop and launch Total Hydrogen Solutions, a division of Pneumatic and Hydraulic Company. I joined to start its hydrogen division, and within the first two years it closed the largest sale in the 65-year-old company's history. Now I also develop projects as a cofounder of Total Hydrogen Development.

Scroll and the whole value chain slides past. The molecule will tell you what's happening to it. Tap any pin to see what I built there, with real photos and an honest status.

  • Demonstrated
  • Delivered
  • Tested
  • Operational
  • Announced
  • THS product line
Start at the tap ↓
The white CHRS refueling cabinet with its gauge window and nozzle holster
The CHRS cabinet, Houston, 2023
Stage 1 of 6 · Water
Badges count my projects at each stage
Schematic of the hydrogen value chain from water to a vehicle or power unit. A hydrogen molecule moves through it as you scroll. 01 · WATER O₂ to the sky 02 · ELECTROLYSIS 03 · COMPRESS 04 · STORE 144 05 · DISPENSE 06 · DRIVE OR POWER
H₂ says~1 barHi. I'm two hydrogen atoms stuck to an oxygen. In other words: water.
Per day
50L water<0.1garden hoses11.5kW avg40kg O₂1Mirai fill-ups

01 · Water

Every kilo starts as water.

Hydrogen is H₂. The easy place to find it is H₂O, stuck to an oxygen atom. Chemistry says 9 kg of water per kilo of hydrogen; I plan on about 10 liters.

Engineer's note2 H₂O → 2 H₂ + O₂. By mass, 9 kg of water holds 1 kg of hydrogen and 8 kg of oxygen. Feed water is purified first and some is lost, so about 10 L/kg in practice.

I always tell people the water for 5 to 6 MW of electrolysis fits through an average garden hose.

Projects here

None of mine light up here, and that's the point: water is the easy part. Tap the scale buttons above and watch the daily water jump.

02 · Electrolysis

Electricity in, hydrogen out.

DC current splits water into hydrogen and oxygen. The machine is an electrolyzer; its repeating cells are the stack. Flavors: alkaline (the old workhorse), PEM and AEM.

Engineer's noteA kilo of hydrogen holds about 39.4 kWh (higher heating value). Whole systems typically draw 50 to 60 kWh per kilo; the numbers here use 55, which you can change below the journey. The rest leaves as heat.

Katy taught me the sequence decides the project, not the stack: power, rectifiers, utility interconnect, building, offtake.

Projects here · tap one · swipe

03 · Compression

Squeeze the lightest gas there is.

At room pressure a kilo of hydrogen fills about 12 cubic meters. A car carries about five kilos. So the gas gets squeezed, a lot.

Engineer's noteElectrolyzer out at about 30 to 35 bar into a buffer, then gas boosters to 700 bar for vehicles. Pneumatic boosters, hydraulic boosters and diaphragm compressors get combined for different pressures and flows. Squeezing heats the gas, so every stage needs cooling.

At HNO the hero tech rarely failed; the valves, fittings, transformers and breakers around it did. That's why I call us fancy plumbers, electricians and HVAC technicians.

Projects here · tap one · swipe

04 · Storage

Make it steady. Sell it in bursts.

Electrolyzers like to run steady; drivers show up in bursts. Storage is the buffer, split into pressure banks so a car fills from the lowest bank that can still push gas in, then the next.

Engineer's noteRule of thumb: 200 to 300 bar is usually the cost sweet spot for bulk storage once you count compression; high-pressure banks are for fast vehicle fills. The Katy datasheet draft listed storage capability up to 1,035 bar.

Past about a day of stored energy, batteries just don't cut it. Against a big tank, the big tank usually wins.

Projects here · tap one · swipe

05 · Dispensing

The only part a driver ever sees.

The dispenser meters the gas, talks to the car and fills to 350 or 700 bar. Fast fills heat the tank, so the hydrogen gets pre-chilled first.

Engineer's note350 bar is common for buses and forklifts; 700 bar is the car standard, which is what the Mirai uses. That 144 on the little screen in the drawing is a nod to a real CHRS photo.

A mobile refueler is a gas station on a trailer. The trial unit graduates into the fleet instead of getting thrown away.

Projects here · tap one · swipe

06 · Vehicle or power

And back to water.

In a fuel cell the hydrogen meets oxygen from the air again: electricity, a little heat, and water. Or feed a little hydrogen into a diesel engine, which is where I started.

For years, building hydrogen demand felt like farming the desert. San Bernardino felt like open, fertile ground.

Projects here · tap one · swipe

CHRS, the "Chris unit"

Prototype · demonstrated a Mirai refuel

HNO International with Varea Energy · 2023 to 2024 · built at Greentown Labs Houston

A compact station that makes hydrogen from water on site, then compresses, stores and dispenses it. The 5 kg/day demonstration version ran five Enapter AEM electrolyzers plus a dryer, dispensing at 350 or 700 bar from a cabinet about 6 ft × 4 ft × 6 ft with a digital HMI. A Jan 9, 2024 release reported it refueled a Toyota Mirai in Houston. HNOI later wrote off the prototype asset: it stayed a demonstration, not a product line.

My rolePartnerships lead, spec owner, procurement lead (electrolyzers, booster, chiller, tanks), and the engineering scope handed to the controls firm.

A tall black rack holding five stacked electrolyzer modules
Five stacked electrolyzer modules
The CHRS cabinet door open showing gauges and valves
CHRS, door open: gauges and valves
Design render of the CHRS cabinet
Design render: CHRS
The CHRS cabinet strapped to a trailer behind a pickup
CHRS strapped to a trailer, Oct 2023

Katy SHEP plant, the first big one

Designed and specified · operational 2026

HNO International · 2023 to 2025 · Katy, TX

Announced in Feb 2024: HNO International, Element One Energy and Pneumatic and Hydraulic Company to build a 1.25 MW, 500 kg/day alkaline green hydrogen plant in the Houston area. Compression by Haskel boosters integrated by PHC; the datasheet draft listed storage capability up to 1,035 bar (15,000 psi).

My roleWrote the plant requirements (March 2023) and the datasheet draft. Owned the electrolyzer vendor relationship, the rectifier spec (two ~4,000 A rectifiers, fed at 12 kV), and the storage and compression workstreams.

Katy taught me the sequence decides the project, not the stack: power, rectifiers, utility interconnect, building, offtake.

Isometric design render of the SHEP layout
Design render: SHEP layout
Office and warehouse building with Pneumatic and Hydraulic and Total Energy Solutions signage
Pneumatic and Hydraulic / Total Energy Solutions building, Katy, TX
An electrical substation seen from a dirt lot
Electrical substation from a dirt lot, June 2023 (location not confirmed)
Rows of white power-distribution panels in a warehouse
Power-distribution panels in a warehouse

Smaller cells, same lesson

Product and concept

HNO International · 2022 to 2024

Hydrogen Carbon Cleaner (public as an HNOI product): an HHO carbon-cleaning cart for mechanic shops, redesigned to run on a standard 110 V, 15 A circuit.

My roleProject manager for the system design.

SeedH2 (2022): a compact PEM stack concept entered in Phase I of the DOE American-Made Hydrogen Shot Prize.

Inside the Carbon Cleaner prototype cart
Hydrogen Carbon Cleaner prototype: inside
A black cart with an E-stop and a clear bubbler tube
Carbon Cleaner cart with E-stop and bubbler
An opened LeefH2 box showing a clear electrolyzer cell
LeefH2 opened: the electrolyzer cell

THS production packages

Delivered

Total Hydrogen Solutions · since Aug 2023

We package electrolyzers with the water treatment, drying, compression and controls around them. Delivered: a 2 kg/day electrolyzer, booster and 3,000 psi storage package for a chemical manufacturer (2025), and a 1 kg/day mobile electrolyzer prototype (2025).

A hydrogen production system on the shop floor
Production system, in integration
A containerized electrolyzer on site
Containerized electrolyzer, on site

Representative THS photos, not photos of the specific jobs named.

CHRS boosters

Prototype · demonstrated

HNO International · 2023

From a booster on the bench, to a plumbed skid, to a fueling panel on a cart.

My roleProcured the CHRS booster.

A stainless skid with a gas booster and plumbing
Booster skid with plumbing
A stainless booster fueling panel with gauges on a cart
Booster fueling panel on a cart

The Hyfindr shop tour

Delivered systems

Total Hydrogen Solutions · Hyfindr Tech Talk #39, published Sept 4, 2024

Hyfindr came to our shop in Texas to film how a compression system works: electrolyzer output into a buffer, boosters to 700 bar, safety in layers, and why integration drives cost. Delivered since: dual hydrogen boosters for a Canadian marine-tech company (2025) and a syngas booster for a research company in Massachusetts (2026).

A compression system on the shop floor
Compression system, in integration
A dual hydraulic compressor
Dual hydraulic compressor

Representative THS photos, not photos of the specific jobs named.

THS cascade racks

THS product line

Total Hydrogen Solutions

Banks of cylinders racked, piped and valved so a station can draw from low, medium and high pressure in turn.

Cascade storage racks on a shop floor
Cascade storage racks
High-pressure storage cylinders
High-pressure storage

CHRS fills a Toyota Mirai

Prototype · demonstrated a Mirai refuel

HNO International · public release Jan 9, 2024

HNO announced that the CHRS successfully refueled a Toyota Mirai in Houston. The HMI shows the vehicle data and pressure live during a fill.

The CHRS HMI with dials reading 144 bar and 18.4 degrees C
CHRS HMI during a fill: 144 bar
A fueling nozzle on a Toyota Mirai receptacle
Nozzle on a Toyota Mirai receptacle
The CHRS fueling a Toyota Mirai in a lab room
CHRS fueling a Toyota Mirai
The CHRS dispenser in a shop
CHRS dispenser in the shop

THS mobile refueler

Built · video tour April 2025

Total Hydrogen Solutions

A trailer that compresses, stores, chills and dispenses. I led the "Inside Look at Mobile Hydrogen Refueling Station" tour (opens YouTube).

A mobile refueler is a gas station on a trailer. It parks, plugs into power and stays for months or years.

A mobile refueling trailer filling a vehicle
Mobile refueling trailer, filling a vehicle
Hydrogen dispensing
Dispensing

LeefH2 and the Hong Kong airport pilot

Pilot · Phase 1 accepted, 2021

HNO International · 2020 to 2022

On-demand hydrogen injection for diesel engines, with a target of 10 to 25% fuel and emissions reduction (a target, not a measured result). A Phase 1 pilot was accepted in Nov 2021 for ground support equipment with an aircraft maintenance company at Hong Kong International Airport: the first commercial contract I helped land.

The green LeefH2 enclosure
LeefH2 unit

LeefH2S on a school bus

Tested · 2023

HNO International · 2023

Hydride-tank hydrogen storage and delivery for diesel fleets. Instrumented testing on a 2012 school bus in Sept 2023, with a university student team and a data-logging partner.

A yellow school bus parked on gravel
The test school bus, Aug 2023
A hydride storage box with a DANGER HYDROGEN label
Hydride storage box with a DANGER HYDROGEN label

Tom's Truck Center

Announced

Total Hydrogen Development · Santa Fe Springs, CA

Hydrogen fueling for heavy-duty trucks, developed through Total Hydrogen Development.

A heavy-duty fuel cell truck at a fueling site
Heavy-duty fuel cell truck at a fueling site

San Bernardino International Airport

Announced

Total Hydrogen Development · San Bernardino, CA

Hydrogen production and fueling at the airport. I'm quoted in the public release as Project Lead, Total Hydrogen Development.

For years, building hydrogen demand felt like farming the desert. San Bernardino had already cultivated its customers. It felt like reaching open, fertile ground.

The airfield at San Bernardino International Airport
Airfield, San Bernardino International Airport

Fuel cell power

THS product line

Total Hydrogen Solutions

Not every molecule ends in a vehicle. THS sells complete power stations as well as refueling and production.

A fuel cell backup generator
Fuel cell backup generator
A fuel cell power unit under test
Fuel cell power unit, under test

Passport stamped · PowerPoint vs. built

Where the molecule actually went.

  1. 01Water
  2. 02Electrolysis
  3. 03Compression
  4. 04Storage
  5. 05Dispensing
  6. 06Vehicle or power

Hydrogen is full of renderings. Here's my honest scoreboard: what got built and shown, what got delivered, what stayed a concept, and what's announced.

Built and shown

  • CHRSPrototype · refueled a Toyota Mirai (Jan 2024 release)
  • LeefH2 Hong Kong airport pilotPhase 1 accepted, Nov 2021
  • LeefH2S school busInstrumented test, Sept 2023
  • Hydrogen Carbon CleanerPublic HNOI product; I managed the system design
  • Katy SHEP, 1.25 MWDesigned and specified · operational 2026

Delivered at THS

  • Syngas boosterResearch company, Massachusetts, 2026
  • Dual hydrogen boostersMarine-tech company, Canada, 2025
  • 2 kg/day electrolyzer + booster + storageChemical manufacturer, 2025
  • 1 kg/day mobile electrolyzerPrototype, 2025

Concepts and what's ahead

  • SeedH2Concept · DOE Hydrogen Shot Prize Phase I entry, 2022
  • Tom's Truck CenterAnnounced · Total Hydrogen Development
  • San Bernardino International AirportAnnounced · Total Hydrogen Development

Small projects moved fast. The big one took years.

Portrait of Greg Heller

Got a molecule that needs a path?

Tell me the goal, not the product. I'll work backward from it.

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