Snippets on Energy #2

Resource Intensity

If it looks impossible, it is because it’s indeed impossible. Image credit: Visual Stories || Micheile via Unsplash

“Anyone who believes exponential growth can go on forever in a finite world is either a madman or an economist”

Kenneth E. Boulding

esources on Earth are finite. Each and every one of them. If it doesn’t replenishes itself fast enough for your needs, you can be sure that one day you will run out of it. Coal. Oil. Natural gas. Metals. They will run out one day, and as I wrote many times before, their availability might already have started to decline. Some would argue, that we have an “infinite” energy source up there, the Sun, but at the same time failing to consider two very important aspects: that one, its energy is diluted, and two, we still need technology to harness its power.

What is this? This is a mini-series on the energy transition dilemma. If you are new to the topic, please read the kick-off article for the sequence titled: The crux of the energy transition. ..and now, back to the show:

Let’s start with problem one: that, solar energy is very-very-very diluted. It has a very-very-very low energy density, especially when it comes to powering our civilization (see Snippets on Energy #1). The same is true for wind (another form of solar power), or hydro (also driven by evaporation and precipitation). In other words: the Sun’s energy has to be captured, concentrated and transformed before we can use it. Plants are doing exactly this type of job in the ecosystem, are 100% renewable and take care of their own maintenance and replenishment.

Humans are not plants however, thus we need technology to harness the Sun’s energy. Be it photovoltaics, wind, hydro, wave, etc. these methods all require us putting up something to capture that energy, and convert it into electricity, or other useful forms of energy (kinetic, heat etc.) It requires us building material stuff. Metal structures. Silicon panels. Concrete foundations and roads. All of which needs energy and further material investment in mining, smelting, manufacturing, transportation, installation, maintenance and repair. All of which are finite in quantities, and contrary to modern beliefs, do not grow on trees. This is why material resources matter — and in fact are a great bottleneck— when it comes to energy.

his, as you might have already guessed, has nothing to do with money — be it conventional currency or whatever-coins. When physically mining a resource becomes energetically uneconomic (i.e.: requiring more and more energy to recover, while what it provides when put into use remains the same) it soon becomes a net waste of efforts. Take copper, the most important metal for electrification and for building out “renewable” power for example. The ore grades are falling year by year, meaning that we need to blast away more and more stone to get the same amount copper. Today we are approaching a ratio of 1% metal vs 99% rock. All of which has to be hauled uphill from a hole, milled to ever smaller grains, as the metal is ever more evenly dispersed within the rock… This effort requires exponentially increasing amounts of energy year over year. This is where we are today. Not somewhere in the far future. Today. And we haven’t even started building out our “renewable” grid at scale yet.

Copper ore grades are falling around the world. Reason: higher grade minerals were mined first, and now all what left is low grade rock. Image source:

Putting these two concepts (the low energy density of “renewables” and the imminent decline in material reserves) together makes it clear that the “renewable” future as it is marketed today, is impossible. Not gonna happen. Ever.

This graph from the International Energy Agency tells it all:

Material requirements of our “renewable” future (SDS) vs reality.

Remember this: all what you have seen so far (cheap metals, cheap labor and as a result cheap “renewables”) was all made available by cheap fossil fuels. All of the technologies required to mine, process, manufacture, transport and install wind and solar are fully dependent on oil, coal and natural gas. Once these dense sources of energy are gone, it will become impossible to replace ageing “renewable” infrastructure, let alone growing it.

he less energy dense a power source is, the more you need to build from it. Where back in the fossil fuel era all you needed was a diesel generator, now it needs to be replaced with literally tons (1) of photovoltaic panels and batteries. The power to weight ratio is just so incredibly bad, that you need to increase material consumption at least tenfold (!) just to be in the same place. This is what you have seen on the IEA chart above — our material desires departing from the realities of a finite planet.

There is an ecological, geological and economic limit when it comes to maintaining, let alone growing our energy use. Especially when we are “full steam ahead” in converting our energy base into something very diluted. With low energy density the capital and repair costs will simply become too huge to maintain. We are already facing this very issue with fossil fuels. Yes, mathematically we might have 40 or 50 years of oil left, but extraction costs went up so badly, that companies are less and less inclined to invest in replacing depleting wells. The technological reasons are complex (smaller fields, deeper wells, harsher environments, higher energy inputs thanks to “enhanced” oil recovery, unconventional resources etc.) but the results are clear: less and less “production” capacity and flexibility. ESG “green” capital and COVID were really just the final nails in petroleum’s coffin.

What about nuclear? Well, Uranium-235 is a finite resource too. Contrary to the hopes of nuclear advocates Thorium and other high tech reactors (not to mention fusion…) is nowhere near to widespread adoption. France and China has just recently announced that they will continue down the path of building conventional nuclear reactors, leaving no hope for alternative technologies to emerge at scale in the coming decades. Resource intensity wise nuclear is also much worse than a commercial combined cycle gas power plant: it needs millions of tons of concrete and stainless steel for safety reasons, whereas a simple gas turbine works perfectly without them... I’m not saying that natural gas is good as it is still contributing to climate change in many ways.

Resources on Earth are finite. Recycling doesn’t come into the picture yet, since first we need to add new power generation capacity. Pipes, refineries and coal fired power plants cannot be turned neither into solar panels, nor into wind turbines. We have to mine the necessary resources at ever diminishing returns at a scale well beyond the planet’s capacity to provide, and at a risk of additional habitat destruction.

With that said, wind and solar will play a significant role in our future, just not in a way how most of us imagine today.

Where is our flexible and scalable energy supply then, needed desperately for growth? How do we fulfill this imperative then? We will see into these questions in the next installment of Snippets on Energy later this week.

Until next time,



(1) A typical 6 kW generator weighs around 100 kgs (220 pounds) while if you want to have the same amount of electricity, 24/7 you would need — realistically speaking— 100 sqm of panels (1000 sq foot) producing 20kW under perfect conditions, but about 6kWh on a 24-hour average (considering daylight hours, clouds, misalignment, etc.), weighing 2800 pounds or 1270 kgs (1.27 metric tons), plus the battery pack, plus an inverter.