Why we shouldn’t rely on space mining to solve mineral shortages

I have been seeing a lot of speculation lately about how space mining will solve the critical mineral shortages that will be coming in the future. All of the talk about mining the moon, Mars and the Asteroid Belt strikes me as the ludicrous fantasies of people who don’t want to accept the resource limits that humanity faces.

It is understandable why people see space mining as a solution, as they survey the growing demand for minerals. According the US Geological Survey, the world mined 26 megatons of copper in 2022, but only has 890 megatons of copper reserves. Assuming that no more reserves are found, at the current rate of consumption, we will run out of copper in 34.2 years. Rising prices and new extraction techniques will make it possible to mine copper in more places on the planet, but we will also need massive amounts of copper to switch the world from running on fossil fuels to renewable energy. Today’s electric vehicles contain 3 times more copper than internal combustion engine vehicles, so futurists worry that lots more copper will be needed to electrify all transport.

The world won’t run out of copper in the next 3 to 4 decades, but it will get much harder to extract, as mining companies have to switch from sulfuride ores to laterite ores, which means moving a lot more earth and consuming a lot more energy to extract the same amount of copper. Mining will have to move to lower grades of ores with lower concentrations of copper and operate in more remote locations such as the ocean floor.

Why hydrogen won’t be the fuel of the future, but it will be a vital chemical input

Since the invention of the Grubb–Niedrach fuel cell in 1958, which was used in NASA’s Gemini missions, hydrogen has been touted as the fuel of the future. Advocates of hydrogen bemoan the lack of investment, but they are convinced that hydrogen vehicles are just around the corner and every electric utility will be generating hydrogen for energy storage within a decade. Despite all the hoopla, the imagined hydrogen boom never seems to arrive. Instead, it remains the perpetual domain of venture capitalists and vague long-term plans that are unlikely to ever come to fruition. It is necessary to do the math to understand why businesses aren’t investing in hydrogen in a major way despite decades of generous government subsidies and grandiose plans.

The fundamental problem with hydrogen is the amount of energy which is lost in its creation and conversion back to usable energy. If creating hydrogen from water, first between 30% and 37% of the energy is lost in the electrolysis to split H2O into H2 and O. Then roughly 10% of the energy is lost in compressing and storing the H2 and even more is lost if the H2 is liquefied by cooling it to under −253°C (−423°F). If compressed and transported via truck to a hydrogen fueling station, roughly 20% of the energy will be lost. Then, the hydrogen is passed through a fuel cell, such as a proton exchange membrane (PEM) in an automobile, an alkaline fuel cell (AFC) in a submarine, a phosphoric acid fuel cell (PAFC) in a commercial building’s generator or solid oxide fuel cell (SOFC) at a power utility that also needs both electricity and heat. The fuel cell splits the H2 molecule into two hydrogen protons (H+) and two electrons (e-). Then combines them with oxygen (O₂) molecules from the air to create water and free electrons. One O₂ molecule and two H₂ molecules will generate 4 free electrons for electricity:
   2H₂ + O₂ → 2H₂O + 4e-
In this conversion from hydrogen + oxygen to water + electricity, phosphoric acid fuel cells lose 60% of the energy, molten carbonate fuel cells lose 50%, and alkaline and solid oxide fuel cells lose 40%. Proton exchange membrane fuel cells lose between 30% and 40% of the energy, so the fuel cells in automobiles are relatively efficient, but the membranes are expensive and they wear out too fast for use in a power plant.

Why net zero GHG emissions by mid-century is an achievable goal and we shouldn’t give up

Climate science demands that the planet gets to net zero greenhouse gas emissions by 2050 to avoid over 2 degrees C of global warming. The Conference of Parties negotiations at the UN still maintain that global warming can be limited to 1.5°C, but that is a fantasy considering that 2023 is now expected to be 1.40°C over the historical average between 1850 and 1900. James Hansen now says that 2°C of global warming is inevitable and 3°C is likely, and I trust his math far more than the IPCC AR6 report, which was edited for political considerations and the need for scientific consensus.

Even at current agricultural production levels, we are going to have trouble feeding the expected global population of 12 billion by 2050. Production of the principal caloric crops (wheat, rice, corn and soybeans) is expected to drop significantly over 2°C of warming and collapse over 4°C, so we are looking at a very dire future with widespread famine and the breakdown of global trade when the principal grain producers (US, Russia, Brazil, Argentina, Ukraine, etc.) start restricting exports in order to feed their own populations.