Hydrogen can be a worthy co-contributor to a battery-based economy, but the large stumbling blocks will be safe production, dispensing, and storage away from commercial facilities (i.e. parking garages and residences). I, for one, dream of a near gas-station-free world with hydrogen being heavily-regulated by a utility-based system, no longer a decentralized price-gouging mecca for private energy giants and colluded with by large auto/ truck manufacturers. With hydrogen hook-ups as (or more) prevalent than natural gas, energy pricing can soon be a not-for-profit, municipally-controlled system. With home and work re-charging becoming more widespread, supplemental fuelling by hydrogen can be instituted on freeways and convenient public areas, especially for those larger vehicles where battery technology has not yet overcome the current weight to range/ pull ratio. Now is the time, local municipalities, to stop hydrogen vehicle fuel from falling predominantly into the private sector.

We can make hydrogen from bio methane at the fueling points.

A very useful report. It would seem that by using today's strong profits, the oil industry should be able to accelerate research for creating the distributable product they seek - gaseous hydrogen - from fully renewable sources of solar and wind. With that objective, the industry will have support and credibility with all parts of society.

The most attractive market for hydrogen is for transportation, where refueling convenience - traditional locations and speed - give hydrogen a sizable advantage. However, battery technology is moving surprisingly fast, and the economics of hydrogen become more challenging with each battery advancement. Tesla's Battery and Powertrain Investor Day is coming soon, and this will likely establish a new, higher set of goals that hydrogen must meet.

EP stated: "Back in 2004 I calculated that it would take about 180 GW average electric power to convert the USA from petroleum to battery-electric."
Reply: No one is talking about completely replacing battery-electric transportation. You're still in the mindset of dispatchable thermal power plants supplying the grid. When the future will comprise of non-dispatchable Solar and Wind intermittently, and non-dispatchable nuclear plants providing constant base-load, then sometimes we will have too much power that will burn out the grid, necessitating the storage of this grid-excess by making Hydrogen. Other times, we won't have as much, needing to fire up hydrogen-fueled thermal power plants for backup.
In this fluctuating situation, the best option would be a Plug-in FCEV to run on grid electricity during the seasons with surplus of RE like in Springs and Falls due to low electricity prices. In Winters and Summers, overall energy consumption will exceed RE supply, necessitating the use of Hydrogen due to much higher prices of grid electricity because backup hydrogen-fueled power plants will have to crank up to make up for the shortage of RE.

The use of a Plug-in FCV will permit the users to choose the cheapest source of energy, depending of season.

No generators, no big turbines, no moving devices, no noise, no smoke. Electricity from hydrogen fuel cells can produce anywhere, from a few watts to hundreds of kilowatts or hundreds of megawatts for every need, from remote areas, remote areas, or power stations, buildings to to cities, without the 2 player games need for massive power plants and grid power from the national power distribution center. Consumers can produce electricity by themselves. Producing electricity with hydrogen fuel cells will break the monopoly in electricity production and distribution.

You're still in the mindset of dispatchable thermal power plants supplying the grid. ,,, Other times, we won't have as much, needing to fire up hydrogen-fueled thermal power plants for backup.

I couldn't have made this up.  Do you listen to yourself?

My mindset is actually in dispatchable (but mostly running 100% all the time) small-ish fast breeder reactors supplying electricity and district heat, with surplus generation devoted first to waste gasification/vitrification and then to biomass processing for fuels and chemicals.  My calculations suggest that the heat production would easily warm every area that is dense enough to support the distribution system, with plenty left over.  The real issue is industrial process heat.  The USA uses about 700 GW(th) of process energy, and the exact temperature of use determines whether this can be supplied by low-grade heat from spent steam, direct nuclear heat, or requires electric heat or combustion.  I don't have a breakdown of consumption by temperature.

Thermal-spectrum thorium breeders would work too (somewhat higher temperature than sodium-cooled reactors can sustain) but we haven't run a molten-salt reactor since 1969 and never actually did a breeder, so that would take a fair amount of R&D time before we could roll them out.  LMFBRs would do a much better job of getting rid of our "high-level waste" (aka fast-breeder feedstock).

@Yoatmon,
1.. The CO2 waste during steam reformation of Natural gas is already pure and at 3,000-psi pressure, ready for injection into depleted oil and gas wells as a supercritical liquid. The H2 can be piped to the end users already decarbonized, as a zero-emission fuel. This is important in the interim as solar and wind capacity are being built. We can have zero-emission fuel today.
The H2 can be piped to each home via existing natural gas local piping system.

2.. In time, more and more Solar and wind farms will be built to replace depleting natural gas reserves. Using steam instead of water, and counting the Higher Heating Value (HHV) of Hydrogen, will result in over 90% efficiency for electrolysis.
3.. When Hydrogen will be used mainly in the winters with waste heat utilization, we obtain higher efficiency from the fuel cell. For example, your home-based Fuel Cell unit can charge your EV or your Plug-in FCV during a cold winter night, with the waste heat used to keep your bedroom warm. In the AM, you do your initial drive using the FC for waste heat to warm up the cabin, and then shut down the FC and continue your trip on battery power.
4.. In the summers, the waste heat from H2 used in distributed heat and power co-generation can be used in vapor-absorptive cooler to provide cooling, thus extending the efficiency of the power generator.
5.. In Springs and Falls, the mild temperatures greatly lessen energy demand, while generous sun and wind energy will result in vast amount of grid-excess electricity to charge your Plug-in FCV (PFCV), to commute mainly using very cheap grid electricity.
6.. In the Summers, energy demand is the highest of all seasons, double or even triple, depending on latitude, while the solar and wind energy cannot keep up with such huge demand, forcing the use of home-based FC or gas-turbine power plants, and this will raise the price of electricity several folds. As such, it may be cheaper to drive your Plug-in FCV using Hydrogen.

7.. With future advance batteries that can provide 650-mi of range for BEV's, we can use 1/5th of this pack to make a Plug-in FCV with 100-mi of electric range, in order to make 5 times more PFCV's for the same amount of precious high-energy-density battery available. Each of these 100-mi PFCV can be driven 90% of the time on electricity alone. So, the superior efficiency of battery will still be preserved, while using H2-FC system to produce 5 times more vehicles out of a given quantity of battery. So, what's good for the goose is good for the gander, as battery technology and energy density will gradually improve, BOTH PFCV and BEV will benefit.

So, the energy picture will be quite complex, and we will be using different forms of energy at different times, depending on which will be most available and which will be the cheapest. Certainly, we will use Solar and Wind electricity directly whenever available, while resorting to Hydrogen whenever this will be necessary. Note that Hydrogen will be very important for the production of fertilizer, for steel production, for space heating, for chemical industry, and for trucks, trains, ships, and planes in the form of liquid H2... etc...

We absolutely need to decarbonize current uses of hydrogen.

But given that 90+% of hydrogen is made from natural gas, any near-term plan to increase hydrogen use is not decarbonization, it's a giveaway to the fossil fuel industry. All you people excited about hydrogen heating and piping hydrogen to the home, look again at their own diagram! it calls for "blended H2 heating" by 2026. Gas companies are talking about adding no more than 20% hydrogen to the existing gas grid. Even if we magically get to 25% of hydrogen made renewably by then, that's only a 4% decarbonization!

The gas companies aren't stupid. They see a future where new construction is purely electric-powered, with more efficient heat pumps for space and water heating, and no gas hookup. They know that most hydrogen will come from cheap natural gas for the foreseeable future. So obviously they're all in on promoting the Hydrogen Economy™; but without firm commitment to make similar percentage of hydrogen renewably as electricity is made renewably, the hydrogen future continues to be a natural gas future. Please don't be fooled.

Roger, you've drunk the Kool-Aid; skierpage has it right.

Going to huge efforts to capture and store intermittent flows of energy is a fool's errand.  It is DESIGNED to fail.  The USA is literally sitting on (in warehouses, mostly) enough energy to supply the whole country for 400 years even if synergies are ignored.  That energy is in the form of depleted uranium, the tailings left over from enrichment for weapons and reactor fuel.  Under 1100 tons/year would do it for the US, and 10,000 tons/year for the whole world.  There's literally millions of years more in the oceans at that rate of consumption, and rivers add some 30000-odd tons every year; the equilibrium between the oceans and the crust means we can never run out of it.

Current US primary energy consumption is about 3.3 TW(th).  At that rate and 45% thermal efficiency (assuming a recompression CO2 cycle replaces steam) we'd have a bit under 1.5 TW(e) of electric generation.  Space heating in urban areas would be covered by nuclear-powered district heating systems, and DHW driven by heat pumps (fed by the district heating water where available).  Right there, most of your need for storage just disappears as you are producing more heat than you can use.  Molten salt heat storage is sufficient to buffer daily demand cycles.  PHEVs using biofuels as their backup decarbonize all ground transport.

All of this is doable with 70's technology... some of it 1870's technology.  What are we waiting for?

EP stated: "Going to huge efforts to capture and store intermittent flows of energy is a fool's errand. "
Reply: Yet, that is the basis of all forms of life on Earth, and that was THE ONLY energy source for all human civilizations prior to the discovery of fossil fuel. Photosynthesis is 0.5-1% efficient, while current PV panels can obtain 20% efficiency which result in 15% efficiency when storing solar energy as Hydrogen. So, we have a huge efficiency gain of 20 folds using PV panels vs crops and forest.

There is no denying that nuclear energy is also very viable energy source, but with Renewable Energy, we are picking the lowest hanging fruit, and we can supplement RE with nuclear in locations where RE is not cost-effective. Furthermore, nuclear energy is very important for space travel in the near future, to greatly shorten the duration of interplanetary trips, so nuclear energy must be conserved as much as possible, for future generations.

that is the basis of all forms of life on Earth, and that was THE ONLY energy source for all human civilizations prior to the discovery of fossil fuel.

Photosynthesis (NPP, net primary productivity) can't support an industrial society.  We learned this the hard way, by almost clear-cutting entire countries for fuel.

Photosynthesis is 0.5-1% efficient, while current PV panels can obtain 20% efficiency which result in 15% efficiency when storing solar energy as Hydrogen. So, we have a huge efficiency gain of 20 folds using PV panels vs crops and forest.

Meanwhile US primary energy consumption is running over 100 times basic human metabolism of the population.  "Renewables" still make too many demands on the land to be sustainable.

There is no denying that nuclear energy is also very viable energy source, but with Renewable Energy, we are picking the lowest hanging fruit, and we can supplement RE with nuclear in locations where RE is not cost-effective.

The so-called "low-cost renewables" are much more expensive than wholesale bids suggest.  They are subsidized out-of-market through things like Renewable Energy Certificates.  Wind and solar require about 10x as much steel and concrete per average kW than Gen III nuclear does, and Gen III+ cuts those figures by about half.

The major cost of nuclear power in the West is over-regulation.  It simply is not harmful to have minor things break or leak.  The paranoia over small amounts of tritium is pathetic; cosmic rays generate orders of magnitude more of it and it is distributed world-wide.  We need to scale "protection" way back, mostly for workers but also for the public.  Small releases of radioisotopes which do not bio-accumulate should not even be reportable events.  Slashing the prep time and paperwork for maintenance at nuclear plants will make them much cheaper to run, and getting realistic about the actual risks of radiation to the public will push the balance toward nuclear.

Furthermore, nuclear energy is very important for space travel in the near future

There won't be enough actinides used for space travel to make a difference.  Sunlight is available 24/7 once you're away from a planet, and beamed laser power is going to be a lot lighter than almost any reactor can be.  You just have to be off in space to build it and use it.

Compare 10,000 tons/year to power all human society to 30,000 tons/year dumped into the oceans by rivers, and the 2-4 billion tons already in the oceans.  There is no reason to try to conserve uranium save by switching from LWRs which use 0.5% of it to FBRs which use roughly 100%.