STRATEGIC GAS RESERVES

May 30, 2014 § Leave a comment

A recent report by Gal Luft suggests many measures for Europe to be less dependent on Russia for their natural gas. An intriguing one is that the International Energy Agency (IEA) creates and manages a strategic reserve of a liquid fuel that could be run in gas turbines in times of shortage. In effect it would be a strategic gas reserve in that it would guard against disruptions in the supply of gas. He suggests the liquid be an alcohol such as methanol.

Short term storage of methanol

The concept of methanol as a storage medium for subsequent combustion to generate electricity is not new. But these have all been for short term storage; the methanol to be consumed at the location it was generated. One elegant concept is tied to the “clean coal” technique of power generation known as Integrated Gasification Combined Cycle (IGCC). Here coal is reacted with water to produce synthesis gas or syngas, which is a mixture of carbon monoxide and hydrogen. Typically this is further “shifted” to produce hydrogen and carbon dioxide. The CO₂ is destined to be sequestered in some way and the hydrogen is burned for power.

All coal and nuclear plants face the problem that electricity generated at night is of little value and that during the day there can be peak demand periods in excess of 25% over baseline. Yet they cannot be turned on and off. IGCC plants offer the option to convert much of the syngas in the slack period to methanol. This is a simple chemical process. The crude “fuel grade” methanol could be stored and then burned in the specially modified gas turbines at any time. Peak load periods could be served running the stored methanol. The additional cost to convert syngas to methanol would be about USD 6 per million BTU (MMBTU), not much more than would have been to “shift” to hydrogen. However, this portion of the electricity generation would produce CO₂ and in that way vitiate an objective of the IGCC. On the other hand this would be a clean burn not that different from natural gas.

Strategic storage of methanol

A strategic reserve of methanol in Europe, as suggested by Luft, would have somewhat different economic considerations than the example given above. In the case of the IGCC the plant would only have to consider the cost of production, not the market price. Also, they were using the higher cost fuel only during peak periods, when the electricity sales prices are high and can sustain a somewhat costlier fuel.

A strategic methanol reserve in Europe would have the following characteristics. The methanol could be raw methanol straight out of the reactor with impurities such as DME. The market price for methanol could be expected to be in the neighborhood of USD 25 per MMBTU. The cost would be lower for an impure product, likely discounting USD 4. This would compare against a nominal natural gas price of around USD 10 per MMBTU. But two other considerations could narrow the gap. Strategic reserves are owned by country governments. These entities could collectively own methanol production facilities that then delivered the fuel on a cost plus basis to each reserve. With USD 4 natural gas, this cost plus number could be expected to be in the vicinity of USD 14. It would be even lower when sourced from Qatar or Iran. The price on release could depend upon the situation. In any case releases would take place only in the event of a severe dip in supply, politically or otherwise driven. In that situation the actual market price would be higher than the nominal USD 10, thus narrowing the gap. Besides, the national energy security benefit and the correlated issues of keeping the traditional suppliers such as Russia in line, have value.

Having the IEA take the lead on a strategic gas reserve has precedent. All 28 member countries of the IEA are required by agreement to hold in reserve oil to the tune of 90 days of consumption in the previous year. Net exporting nations such as Norway are exempt from the requirement. Some countries by treaty support each other, such as the US commitment to support Israel with the US Strategic Petroleum Reserve (SPR). The term “petroleum” is interesting because only oil is being stored and yet the term technically applies to all hydrocarbons ranging from oil to natural gas liquids (NGL’s) to methane. This is because the foregoing is part of a continuum in the conversion of organic matter to hydrocarbons. This is why one finds gas associated with oil (much of it being logistically stranded and hence flared) and liquids associated with gas. In the parlance, though, petroleum has become synonymous with oil. This does not prevent oil import/export statistics from counting NGL’s in the figures!

As we have discussed elsewhere, the concept of the SPR for the US is less compelling now. Domestic production is on a rapid rise and new shale oil wells can be drilled and produced in a matter of weeks. In a sense, the shale reservoirs are our reserve. Consequently, the US could offer arrangements to other countries similar to that with Israel. India is a possibility; their current reserve covers only two weeks of consumption. The US has a diplomatic hole to dig out of with the presumed new Prime Minister, having denied him a visa some time back. This could help.

A strategic reserve to guard against gas supply disruptions in Europe certainly has merit. Methanol appears to be the most viable fluid to keep in the reserve. While the storage mechanism is very straightforward compared to storing oil, the economics need to be worked out considering in particular the externalities.

Vikram Rao

Research Triangle Energy Consortium