EDITORIAL COMMENT: Mbire gas confirmation needs planning to start Geo Associates, Invictus and One Gas are now convinced there are at least 13 zones of hydrocarbons in the basin, and that the geological structures capping the layers of this former inlet of the sea since the time of the dinosaurs have not sprung a leak. 

THE confirmation that the Cahora Bassa Basin underneath Mbire district at the north end of Mashonaland Central holds gas and oil deposits is very good news and now needs to start exciting planners of our energy requirements and our chemical and fertiliser industries.

Geo Associates, Invictus and One Gas are now convinced there are at least 13 zones of hydrocarbons in the basin, and that the geological structures capping the layers of this former inlet of the sea since the time of the dinosaurs have not sprung a leak. 

They still need to retrieve fluid samples and fully map the basin with more test drilling, but the results from the first hole have ensured their commitment.

In the short and medium terms as we move towards the commercial confirmation and the search for investors, the gas strike is likely to be easily the most important since we can start using natural gas a lot sooner than the liquids there, which are almost certainly very light fraction fluid hydrocarbons, rather than pure crude oil.

The first obvious use for the gas will be a power station, a big one.

A gas power station is significantly cheaper to build and commission than a coal station, is more efficient and produces around half the carbon dioxide for every unit of electricity generated than a coal station, and so are still accepted by those most keen on lowering carbon emissions.

A gas station has been flippantly described as a jet engine and generator in a shed.

It is more complex than that, but basically it uses a bank of modified jet engines to burn the gas and spin the generators.

The civil engineering is basic, a sound foundation that can take the weight and vibration of the equipment and a roof to keep the rain off.

There is a gas feed from a pipeline and removal of the exhaust fumes, but no cooling towers, no water pipelines, no trucks, no boilers. 

The equipment is off the shelf these days, and the simplicity of the station means that it can be commissioned in less than a year after the contracts are signed and finance sorted out.

Zimbabwe’s energy demand is growing as the economy grows, and as we have already found, we need maximum diversification of generation capacity as well as its expansion, including hydro, coal thermal, solar, wind if possible, and now gas. 

Natural gas needs very little processing before being pumped into a gas power station, which is why we can probably exploit it for power fairly quickly once a commercial well is drilled.

So right now we can start the initial planning, including where we will site this first gas station.

This involves a lot of calculations about whether we have short pipelines from the well heads to the station, and a long extension of our main 330kV national grid, or a long pipeline from Mbire to the power station and little extension of the top end of the grid. 

There are intermediate solutions, such as Bindura, near where the link to the Cahora Bassa power station terminates, and where there is other infrastructure.

But there are other potential uses of natural gas that again can be commissioned quite quickly after commercial drilling starts. 

Sable Chemicals, right back when Invictus first announced there were probable gas deposits, signed a declaration of interest into a pipeline down to Kwekwe where a large part of Zimbabwe’s admittedly modest chemical industry is located. 

Sable would be particularly interested in using the technology that uses natural gas as one of the feedstocks to make ammonia, and so ammonium fertilisers.

There are others in Kwekwe who need some or all the constituents of natural gas, mainly methane along with ethane, propane and butane.

They need to be brought into the planing process as well.

Again we face a planning decision. Would it be better to build a large offshoot of the chemical industry in or near Mbire, or to build a pipeline halfway across Zimbabwe to carry the gas.

In either case it seems we need at least Zesa and Sable to plan together, to figure out pipeline routes if that is the best solution, or where to build a new town near where the well heads are likely to be. 

Sable has been in the doldrums in recent years, and may need a lot of investment to expand to cope with natural gas supplies or to replace what it already has so it can move up the scale.

But if much of the present investment can be used, then more precise calculations are needed over the advantages or disadvantages of a pipeline, and how Zesa can be plugged in.

A new town would need all sorts of other things, such as a decent water supply.

To a degree commercial exploitation of the basin would need a place where staff housing and the production centre could be sited, plus a first-class extension of the national highway. So whatever the Zesa and Sable calculations show we still need infrastructure in the Mbire area.

All this requires a number of people from separate organisations to work together, rather than each trying to be independent, to get the planning sorted out before any commitments are made, and to be able to activate that planning the minute an investor is interested in commercial exploitation of the natural gas and then of the liquids. 

Delays as that moment approaches would be intolerable, as would trying to fit together a bunch of independent but conflicting decisions over where we use the gas.

The liquid condensates are more a longer term possibility for commercial exploitation. 

One point we need to remember is that over a little more than the next decade almost all of the world’s automotive industry is going to move to electric vehicles, and while we will still need petroleum fuels for at least another decade after that switch to cope with older vehicles, the demand will continuously decrease.

The initial Invictus reports thought that the liquids would be what are described as gas condensates, the hydrocarbons that are heavier than natural gas components, but mostly lighter than the those used in petrol and diesel fuels. 

This would require a refinery that combines molecules, rather than distils off and cracks heavier molecules, if we turned the condensates into fuels.

Again we need some planning in view of the rapid rise in electric vehicles and the specialised refining needed for fuels for the declining number of petrol and diesel vehicles.

Perhaps it would be more useful to use these liquid fractions as feedstocks to drive a rapidly growing chemical industry. 

But once again we would be looking at either a long pipeline, perhaps running alongside a gas pipeline, or having a refinery and chemical industry in or near Mbire.

We have time to do a really good job on how we want to plan and site the production, electric generation and many downstream industries that this confirmed presence of hydrocarbons will be giving us, but we need to start that planning now, so that all factors are weighed, aligned and costed, with perhaps the aligning of the different users from Zesa and Sable onwards being the most important.

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