The sudden abundance of natural gas in the US triggered a startling divergence of crude oil and natural gas prices that, in turn, has energized the advocates of using more gas in transportation. Yet despite the availability of wholesale natural gas at less than $0.60 per gasoline gallon equivalent (GGE), and with retail compressed natural gas (CNG) prices under $2.00/GGE in many locations, natural gas accounted for less than 3% of US transportation energy consumption in 2011--most of it attributable to pipeline compressors. The picture is very different in countries like Italy and Pakistan, where CNG has a significant market share in motor fuels. As the US looks ahead to greater reliance on secure domestic gas for road transport, it's worth considering why other countries have such a big head start.
The obstacles to greater market penetration by natural gas in transportation are well known. CNG and LNG (liquefied natural gas) require new infrastructure. Many more retail gas facilities would be needed to assure motorists of convenient access at service stations. CNG takes a separate dispenser and compressor on the forecourt, while LNG requires both a new pump and insulated storage. Where pipeline gas is unavailable, such as in parts of the northeast, additional investments in the local "gas grid" may also be necessary.
Vehicle conversion costs represent another significant barrier. Engine modifications and crash-resistant fuel tanks add significant costs for both new vehicles and retrofits. Even with gas priced well below gasoline or diesel fuel, the payback for these costs can be lengthy. That's one reason that gas has made greater strides in bus, truck and delivery fleets in the US than for personal cars, since the more intensive use of such vehicles substantially shortens the resulting payout periods. Countries with high gas-vehicle penetration typically have government policies and incentives in place to promote the use of gas by mitigating these obstacles.
Italy leads the EU in CNG vehicle adoption, with more than 11% of new passenger cars equipped for natural gas last year. That compares to 0.01% for the US in 2012, where only one CNG model, a Honda, was sold. The Italian government promotes natural gas use in vehicles both directly and indirectly. The country provides a subsidy of €700 ($945) to purchasers of CNG automobiles, while manufacturers like Fiat offer discounts to expand their market for CNG cars. Incentives were even larger a few years ago. The government also makes retail petroleum products extraordinarily expensive with high taxes. So even though Italy is a large net importer of natural gas, CNG is much cheaper than gasoline or diesel at the pump.
Fuel availability may also have something to do with the disparity in adoption rates. Despite having an 83% smaller overall vehicle population , Italy has over 40% more CNG or "Autogas" refueling stations than the entire US, at around 900. This is due in part to state-level incentives, with 50-70% of the cost of a new CNG filling station reimbursed by regions such as Liguria, Lombardy, and Piemonte.
In terms of market penetration, Pakistan, which appears to be self-sufficient in gas, leads the world in natural gas vehicles, at 80%. That translates into over 2 million CNG vehicles, the result of a determined effort on the part of the government to reduce imports of petroleum by shifting to domestic fuels, with gas as its best option. This is a common theme in the non-oil-exporting developing world, where oil imports impose a large drag on national trade balances. CNG use in Iran is even higher than in Pakistan, as an unintended consequence of protracted international sanctions.
For the US, where oil production is increasing and oil imports declining, a shift to natural gas for transportation is likely to remain an opportunity, rather than a matter of necessity. The "NATGAS Act", a bill proposing incentives for CNG and LNG along the lines of the Italian model has languished in the US Congress for several years. It remains to be seen whether this will become a higher priority in the new Congress, which has shown early signs of interest in breaking the recent logjam on energy legislation.
In the meantime, adoption of natural gas vehicles in the US will proceed based on market forces, supported by a small advantage in the way CNG cars are counted in manufacturers' fleets under the stringent federal fuel economy regulations issued last summer. That could lead to natural gas fueling 3% of US vehicles --mostly trucks--by 2020, based on the analysis of a partner at McKinsey & Co. Much like the case for energy efficiency investments, the available savings indicate a much larger potential, but funds for CNG/LNG transport must compete with other priorities.
A slightly different version of this posting was previously published on the
website
of Pacific Energy Development Corporation.
10 comments:
I've always understood that there are two large obstacles to public acceptance for CNG cars that kept gasoline/diesel fueled cars the preferred choice.
One is the limited range of CNG cars requiring more frequent refueling, at least within competitive tank volumes and weights.
The second compounds the first - long refueling times. Even at the high pressures available, one can do a fillup in a few minutes - it takes a considerable amount of time. Fleets that can refuel overnight and have low mileage demands during a single day might not mind but it severely limits personal car range and productivity.
These are the BIG constraints on CNG passenger car market penetrations.
Someone tell me if I'm wrong or out of date!
Sorry - "one can do a fillup in a few minutes" should have read "CAN'T".
NGVs, while they typically have a shorter driving range than gasoline or Diesel vehicles, have a far greater range than EVs; and, they can be refueled far more quickly.
A typical NGV can be refueled at a station with high pressure storage within 5 minutes.
I've never refueled an NGV, but it sounds like Ed might have some experience with it. This DOE site differentiates between fast-fill and time-fill stations, the latter used by fleets: http://www.afdc.energy.gov/fuels/natural_gas_cng_stations.html
It indicates fast-fill of 20 GGE in <5 minutes. That's much quicker than even Level 3 EV recharging (480 V, 400 Amps) and only a bit worse than gas or diesel.
Geoff,
I have been involved in the design, construction and operation of both fast fill and slow fill CNG fueling facilities. I have also been involved in the design, construction and testing of NGVs, including transit buses, UPS delivery trucks, utility service vehicles and passenger cars. I have driven numerous NGVs; and, fueled them as required.
I have now reached the age at which I need a stop at a fueling station about twice as often as an NGV, so the range limit is less of an issue. :-)
A factory-built, dedicated Ford Crown Victoria NGV could easily be refueled at a fast fill station with an automated three stage storage cascade in under 5 minutes.
Couldn't ask for better "ground truth".
Glad I checked the site. I've been updated on the latest then - refilling is much less of an issue now.
Are the high pressure compressors powered by natural gas or electricity? Transmission lines run at surprisingly high pressures but refueling stations must get their gas at a substantially lower pressure in almost all cases. I wonder how much the recompression adds to the cost at the filling point.
Compressors are typically natural gas engine driven. Home, slow fill compressors are typically electric motor driven.
Transmission lines typically are pressurized to 900-1050 psi. Distribution mains are pressurized from 5-50 psi. Vehicles store compressed gas at 2400-3600 psi.
Mr. Reid,
So a natural gas filling station gets its gas at say 25 psi. To do a fast fill, it has to repressurize the gas to 2400-3600+ psi to quickly fill a vehicle.
That takes a good bit of energy at the distribution point which will probably be electric gas compressors.
Here in California we're all in a tizzy because a transmission line feeding San Francisco exploded in a pricy residential neighborhood killing a bunch of people.
Ergo, extending high pressure lines to filling stations will meet with opposition based on safety concerns.
High pressure lines will not be extended to filling stations. The gas will be compressed and stored at the fueling site, using natural gas fueled engine-driven compressors in most cases.
That transmission line in CA was installed long before the homes were built. Therefore, it was not designed for installation in a residential neighborhood. I am not aware that a cause for the failure has been determined.
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