These days net zero emissions, net zero plastics, green energy, clean tech, and references to a “circular economy” populate the headlines, government discussion papers, and strategies of all kinds. Fewer greenhouse gases, less waste, and smaller environmental impacts from human activity are all important goals. And over the past decade, reducing GHG emissions, principally discussed via opportunities for “green” and “clean” energy and related technology, has been at the top of the public policy debate. But with its singular focus on emissions, there is much lost in the conversation about choices, trade-offs, and unintended consequences, with the most important of these being the substantial increase in materials use
accompanied by orders of magnitude higher energy needs.
Beginning with first principles: everything we consume, whether a good or a service, starts with something that’s extracted or grown from the earth. We mine or harvest materials, process and transform them, and then transport the associated final goods and services to consumers. At the end of their useful lives, these “things” are disposed of. Unfortunately, the complex combinations of materials in most of the items we need and use are often unrecyclable because the component parts are too small and mixed with other elements. It is also the case that modern societies depend on highly dense, portable, flexible, and reliable fuels.
And while all energy is in some way derived from the sun, “fossil fuels opened the doors for humanity … [freeing it] from reliance on photosynthesis and current [and available] biomass production as its primary energy source.”
About a billion humans today still live in energy poverty – akin to life during the medieval era.
The 2050 future will include another ~2 billion people in the world, maybe another 10 million in Canada, with at least a million new souls residing in B.C. Each person will seek to sustain or improve their standard of living and obtain the comforts of a middle-class lifestyle. This involves the consumption of innumerable goods and services to satisfy both needs, such as food and shelter, and wants, like vacations and big screen TVs. So, while harnessing lower emissions or emissions free energy sources to augment the global energy portfolio is necessary, the question is at what cost and whether we are honest and transparent about the impacts.
If wind could supply half of the world's energy it would require almost 2 billion tonnes of coal
for the concrete footings and steel towers, and 1.5 billion barrels of oil to make the blades. - Manhattan Institute
Let us acknowledge a few key facts. “Clean” energy is both land- and materials-intensive, consuming immense amounts of construction materials like concrete, steel, fibreglass, plastics, and rare-earth metals. For example, a 100 MW wind farm uses about 27,000 tonnes of iron, 45,500 tonnes of concrete, and another ~800 tonnes of non-recyclable plastics for blades. And because wind energy can only generate electricity when the wind blows, it needs storage to meet demand of consumers and ensure grid stability. In the absence of the latter, electric systems tend to crash since they must always be in balance.
Therefore, a utility-scale storage system is needed to support a 100 MW wind farm, itself requiring ~9,000 tonnes of Tesla-class batteries.
In fact and overall, a clean electricity system requires three times as many machines to produce and store the same amount of electricity generated by fossil fuels, and “two to three orders of magnitude more space to secure the same flux of useful energy if [it were to] rely on a mix of biofuels, water, wind and solar electricity”
compared to today’s system.
Then there is the reality of “clean” machines such as electric vehicles. The raw materials for a single EV battery mean mining, moving, and processing about 225 tonnes of materials. This is 20 times more than what is necessary to produce an internal combustion engine.
While EVs are good for reducing local air pollution, we must acknowledge that rising EV ownership leads to substantial growth in materials and energy use. There is no way around the math.
As for the digital transformation of economies where computing power, data, and automation are key features, it takes 90 kg of steel to produce one pound of energy-intensive pure semiconductor grade silicon. All data systems need enormous amounts of energy for cooling, as well as many thousands of kilometers of fibre optic transmission cable — itself made from energy-intensive glass, Kevlar, ceramics, and glues.
Finally, like all things, machines wear out. “Clean” machines are no different. Wind turbines and solar panels both have about 25 years before needing replacement. The plastic wind turbine blades are not recyclable. In theory, like other electronics, solar panels might be recyclable, but because they are a sandwich of mixed materials — crystalline silicon cells, insulated and protected by sheets of polymers and glass, held together by an aluminum frame, and fixed with a junction box containing copper wiring — dismantling costs are high and the resulting component parts are less pure and therefore less valuable as raw materials. As a result, the International Renewable Energy Agency predicts that, by 2050, there could be up to 78 million tonnes of solar panels reaching the end of their useful lives, and annual solar e-waste of 6 million tonnes.
This non-recyclable solar waste could be two times larger than global plastics waste in 2050.
As a result, it is hard to take seriously claims that moving to “clean and green” is markedly better for the environment when there is little discussion of the quantum of materials needed and the amount of embodied energy inherent in all consumer products. We also rarely examine services in the overall equation, assuming – absent compelling evidence – that an economy based on services is more environmentally benign and uses far less materials and energy. One click shopping is not always cleaner or greener than the alternatives, especially when the purchased items are delivered to the consumer’s doorstep.
Unintended consequences are likely to follow when policies are designed by virtue-signalling political leaders focused on narrow objectives. And while reducing greenhouse gas emissions and other harmful environmental effects is important, a more robust analysis is necessary to understand and measure the collateral impacts of human activity and the trade-offs that inevitably must be made in arriving at collective policy choices.
 US Department of Energy. Quadrennial Technology Review. An Assessment of Energy Technologies and Research Opportunities. September 2015.
 Smil, Vaclav. Energy Transition: History, Requirements and Prospects. 2010. Praeger.; Smil, Vaclav. Power Density: A Key to Understanding Energy Sources and Uses. 2015. MIT Press.
  Mills. Mark P. Mines, Minerals, and “Green” Energy: A Reality Check. Manhattan Institute. July 2020.
 Smil, Vaclav. Power Density: A Key to Understanding Energy Sources and Uses. 2015. MIT Press. p207-208.
 ibid #5.