Under our feet

What is under our feet? I remember from my childhood the brown coal mining areas from where I come from in the Rhineland. While coal mining continues to be expanded, the question about replacing fossil fuels is becoming increasingly urgent. What role does the substrate play here?

Layers of earth close to the surface have been used for industrial raw materials production since prehistoric times: be it for the mining of mineral raw materials such as salts and metals, precious stones such as diamonds or in the search for fossil fuels such as natural gas, crude oil and coal.

In all these cases, something is largely extracted from the soil. But there is also the inverse approach of wanting to store something underground, such as our radioactive waste or the CO2 greenhouse gas; the objective of the latter is to avoid it being further emitted into the atmosphere.

Another type is being added, which is also being increasingly discussed in Switzerland in the course of the climate and energy debate. This involves technologies which in the broadest sense inject water into the soil to then extract energy from it. They include geothermal energy and natural gas extraction with the use of fracking.

In the Basel Deep Heat Mining project and the external page St Gallen geothermal energy project, there have already been two major, important pilot projects in Switzerland exploring deep geothermal energy (¡°deep¡± compared to the surface-based heat pumps and geothermal energy probes). The project in Basel had to be abandoned due to earthquake activity, in St Gallen work has currently been suspended for the same reason; moreover, less water was extracted than expected and there was also a gas eruption.

Further examinations will now have to show how geothermal energy needs to be approached, because geothermal energy is and will remain a key component of external page Switzerland¡¯s 2050 energy strategy. With this strategy, the federal government aims to reduce or even replace fossil fuels and nuclear power by tapping renewable sources of energy, amongst other things.

In (hydro) external page fracking (¡°hydrologic fracturing¡±) a large quantity of water mixed with chemicals and a proppant (for instance sand) is pressed into the subsurface to break up and make porous claystone containing gas. So-called shale gas, which like conventional natural gas consists largely of methane that has a major impact on the climate, can escape through the cracks and be recovered. Shale gas is called an ¡°unconventional¡± natural gas as opposed to conventional natural gas which occurs in deposits that are more easy to mine, so-called natural gas traps.

Fracking is being discussed in a very controversial manner due to possible risks at both a political and social level. As with every technology, arguments for and against it can be presented, and careful consideration needs to be given to whether and what technology, environmental or health risks, etc. we are prepared to take in order to derive which benefit.

However, I would like to discuss, above all, the general extraction of fossil fuels, including unconventional natural gas here.

Over our heads

The third part of the report of the Intergovernmental Panel on Climate Change (external page IPCC) published a few weeks ago leaves ¨C not unexpectedly ¨C no doubt about the fact that we will only be able to mitigate some of the effects of climate change if we reduce the proportion of greenhouse gases in the atmosphere and radically cut or phase out the consumption of fossil fuels entirely.

For me, the quite elementary question arises how the assumed massive global energy potential of unconventional gas fields can support the energy transition. It is often argued that gas can replace coal and, as it contains fewer greenhouse gases than coal, is accordingly more climate friendly. It may indeed be beneficial in some countries.

The example of the US shows, however, that excess unconventional gas does not necessarily result in a reduction in coal mining. Instead, surplus coal is exported at knock-down prices, which boosts its consumption further. At the same time, the incentive to promote innovations in the area of renewable energies and to rely on energy-efficient products and transport, energy, residential and food systems is reduced.

The apparent potential of the unconventional gas achieves quite the opposite in this case. A tax on coal would likely have been able to reduce its global consumption; unfortunately, this opportunity was not taken. The climate policy of every country or convention on international climate strategies therefore also play a key role in the question whether the promotion of shale gas damages or benefits the climate.

It is therefore important to consider precisely what incentives and targets we want to and must set ourselves in order to move towards a low-carbon, resource-efficient and resilient society. We therefore need to be clear about how we want to use our natural resources and which ones we want to find over our heads; only then can we move on to a climate-safe future with peace of mind.