Comment & Debate
Amory Lovins, CEO of Rocky Mountain Institute. “Twenty Hydrogen Myths”. 20 June 2003 – Myth #1. A whole hydrogen industry would need to be developed from scratch. Producing hydrogen is already a large and mature global industry, using at least 5% of U.S. natural gas output. Globally, about 50 million metric tons of hydrogen is made for industrial use each year. That’s over half a trillion cubic meters measured at atmospheric pressure.25 The U.S. Department of Energy (DOE) reports26 that about 48% of global hydrogen production is reformed from natural gas, 30% from oil, and 18% from coal (chiefly in China and South Africa for producing nitrogen fertilizer; half the world’s hydrogen goes into ammonia-based fertilizer). Only 4% of the world’s hydrogen comes from electrolysis, because that process can compete with reforming fossil fuels only under three main conditions: with very cheap electricity, generally well under 2¢/kWh (see Myth #9 below); if the hydrogen is a byproduct (about 2%, for example, is unintentionally made during “chloralkali” electrolytic chlorine production); or perhaps if the producer is charged for carbon emissions and has a carbon-free source of electricity but no way to sequester (keep out of the atmosphere) carbon released from reforming fossil fuels.
U.S. hydrogen production is at least one-fifth and probably nearer one-third of the world total, is equivalent to ~1.8% of total U.S. energy consumption, and comes ~95% from natural gas at ~99% purity from steam reforming and associated cleanup processing.28 Roughly 47% of U.S. or 37–45% of world hydrogen production is reportedly used in refineries;29 it is made onsite, mostly by steam reforming of gas or oil, and is used mainly to make gasoline and diesel fuel. Most hydrogen production by refineries is deliberate, used to make hydrogen-rich refined products or to remove sulfur from them; some is a byproduct of making aromatic compounds. The rest of the world’s hydrogen output goes to ammonia fertilizer, methanol, petrochemicals, edible fats and oils, metal production, microchips, and other products, and a little to special industrial furnaces. World hydrogen production is reportedly doubling about every decade, driven by refineries’ need to make lower-sulfur fuels and by other growth industries. Usage for fertilizer has been relatively flat for the past decade, and usage for methanol is growing more slowly (roughly with GDP) as prospects fade for wide use of methanol-derived MTBE gasoline additive, so the biggest growth market for industrial hydrogen appears to be refineries.
The industrial infrastructure for centralized hydrogen production already exists. Throughout industry, most hydrogen is currently made at large plants and is used at the industrial site or nearby. There are ~1,500 km (~930 miles) of special hydrogen pipelines (720 km or 446 miles in North America) operating at up to 100 bar.30 Moving hydrogen gas through pipelines takes about half as much of its energy as is currently lost when transporting electricity, and the pipeline is far smaller — a 1.7-meter-diameter hydrogen pipeline at 70 bar delivers 16 GW, whereas a 60- meter-tall pylon with three pairs of ±500-kVDC power lines delivers only 9 GW.31 Hydrogen is less dense and takes more compressor energy than natural gas, but also flows better, so transporting hydrogen through existing natural-gas pipelines would deliver only ~20–25% less en ergy, net of compressor consumption32 — thus enabling hydrogen’s more efficient end-use to deliver more service than from the original natural gas flow. Pipelines may also be cheaper, easier to site, and more secure than aboveground high-voltage electric transmission lines.
Hydrogen pipelines normally carry compressed hydrogen gas, not super-cold liquid hydrogen. Only about 1–3 thousandths of all hydrogen produced is liquefied and cryogenically piped, mainly to NASA launch pads for rocket fuel — an ideal use for a fuel whose density is about as low as the denser grades of Styrofoam.
Centralized hydrogen production has coevolved with centralized consumption by major industrial plants. Yet most future uses of hydrogen are not centralized; they’ll serve millions of dispersed customers. This dispersed pattern of usage calls for a different pattern of production, not so much in centralized plants as in small ones near the customers. This can often deliver cheaper hydrogen, because reformers and electrolyzers, which both work well at a small scale, can make hydrogen delivery simpler or unnecessary: instead, they’ll leverage the existing gas and electricity distribution grids, especially during off-peak periods when (by definition) they have excess capacity. Driven by the economics of supply and demand, the hydrogen industry will evolve organically at many scales and for many uses — if it’s not unduly retarded by myths.