How the World Works — Vaclav Smil
Core thesis: The global economy runs on physics, not just financial models. Energy flows, material cycles, and biological systems ultimately constrain all human activity. The numbers are more complex and more sobering than most economic analyses suggest.
Energy
Fossil fuels still provided 84% of global primary energy consumption as of 2019. Wind and solar combined: just 5%. Global energy consumption reached 583 exajoules in 2019 — a fourfold increase since 1965.
Energy transitions happen over decades and centuries. The shift from wood to coal took 200+ years. Coal to oil dominated the entire 20th century. Every energy source requires massive interconnected systems — extraction, processing, transportation, end-use. The global economy has roughly $100 trillion in energy infrastructure that can’t be swapped overnight.
EROI (Energy Return on Investment) typically runs 20–30:1 for oil and gas. Many renewables struggle to reach double digits. Complex civilization requires energy abundance.
Renewable energy’s additional challenges: intermittency, lower energy density, storage at scale.
Food
Global food production must increase 50–70% by 2050 for a projected 9–10 billion people, while simultaneously reducing agriculture’s environmental footprint.
Yield improvements for major crops have plateaued in developed countries. About 30% of the world’s cropland has become unproductive due to erosion and pollution over the past 40 years. Global grain stocks represent only a few months of consumption.
Water stress: 17 countries, home to a quarter of the world’s population, face extremely high water stress. Soil degradation affects 33% of Earth’s soils; projections suggest 90% could be degraded by 2050.
Globalization
Container traffic reached 802 million TEUs in 2019. Boeing’s 787 contains 2.3 million parts from 5,000 factories in 50 countries. International shipping accounts for 2.2% of global CO₂ emissions.
Economic effects are mixed: the share of people in extreme poverty fell from 36% (1990) to 10% (2015), driven largely by globalization in Asia. But U.S. manufacturing employment dropped from 19.5M (1979) to 12.8M (2015). China competition may have caused 2.4 million U.S. job losses (1999–2011).
Recent disruptions reveal systemic fragility: 2011 Thailand flooding disrupted global hard drive production; Ever Given’s grounding held up $9.6B in daily trade; COVID caused a 5.3% drop in global trade volume in 2020.
Risk
Risk categories: natural disasters, technical failures, economic disruptions, geopolitical conflicts.
Risk perception often diverges from actual probabilities. People overestimate dramatic but rare events while underestimating common ones. In the U.S., lifetime odds of dying in a plane crash: 1 in 205,552. Car crash: 1 in 107.
Global catastrophic risks include nuclear war, engineered pandemics, and misaligned AI. Even a limited nuclear exchange could cause a “nuclear winter” and global famine.
Environment
Current extinction rates run 100–1,000 times higher than natural background rates. The WWF Living Planet Index shows a 68% average decline in monitored vertebrate species (1970–2016).
75% of Earth’s ice-free land has been significantly altered. Tropical forests lose 13 million hectares annually. 33% of reef-forming corals, sharks, rays, and marine mammals face extinction threats.
Climate change: global average temperature has increased 1.1°C since pre-industrial times. Under current policies, warming likely reaches 3°C by 2100. Limiting warming to 1.5°C requires cutting global emissions 45% by 2030 and reaching net zero by 2050.
Gap between action and need: carbon capture facilities removed ~40 million tonnes of CO₂ annually as of 2020, versus global emissions exceeding 36 billion tonnes.
Future
Demographic trends: global population will likely reach 9.7 billion by 2050. By 2050, one in six people will be over 65. 68% of the world will live in cities.
AI could add $15.7 trillion to the global economy by 2030, but could also displace 375 million jobs. China is projected to overtake the U.S. as the world’s largest economy by 2028.
Resource challenges intensify: global food demand up 35–56% by 2050, water demand may exceed supply by 40% in 2030, demand for rare earth elements could increase 655% by 2050.
The takeaway: The transition to sustainability will be harder, slower, and more expensive than most projections suggest. But historical precedent shows that major transitions do eventually occur.
See also: _index | carbon-markets-curriculum | 1G-philosophy