efficiency

Minutephysics compares how efficiently different processes convert mass to energy per E=mc^2, from fire and fission to fusion, antimatter and black holes, which can convert a large fraction of mass to energy.

Real Engineering examines the efficiency of hydrogen as an energy carrier. It follows production, storage and fuel cell conversion losses and compares hydrogen cars with battery electric vehicles.

Technology Connections explains why single-hose portable air conditioners are inefficient and often a poor choice compared with window units. It details how the single hose pulls in warm outside air and wastes energy.

A Technology Connections video weighing LED streetlights against high pressure sodium lamps, covering efficiency, color, cost and light pollution. It is a follow-up to his earlier explanation of why street lights are orange.

Wendover Productions explains why modern airliners fly no faster than they did decades ago, covering the economics of speed and fuel efficiency, and why supersonic travel faded.

Engineering Explained works through whether electric cars are really worse for the environment than gasoline cars. It covers battery production emissions, the electricity mix used to charge, and how long an EV takes to break even on lifetime emissions.

Practical Engineering explains pumped storage hydropower, which makes up most grid-scale electricity storage. It covers how it works and why it fits only certain geographies.

Real Engineering analyzes whether electric planes are feasible, focusing on battery energy density limits compared with jet fuel. It concludes electric flight works mainly for short ranges.

Real Engineering looks at the numbers for running California on renewables, focusing on the large energy storage needed. It argues about the cost of batteries and the role of other sources.

Isaac Arthur explores space-based solar power, in which satellites beam energy down via microwaves to rectennas on Earth. He discusses feasibility, profitability and its role in spurring space colonization.

Tom Scott features Kurtis Baute inside a sealed homemade biodome as carbon dioxide builds up, showing how stale air with elevated CO2 affects cognitive function. Sources include studies on CO2 and cognitive scores.

Engineering Explained uses physics to show why today's electric cars, including Teslas, are poor at towing, pointing to battery energy density and weight. It examines Cybertruck and F-150 towing claims.

A two-minute explanation of what a rocket mass heater is, starting from how a conventional wood stove works and why creosote and chimney fires occur. It shows how burning hot and storing the heat in thermal mass makes for an efficient heater.

A Kurzgesagt animated explainer on how humanity could build a Dyson sphere, a swarm of structures capturing the sun's energy. It covers using Mercury's materials and a step-by-step construction approach.

Dave Jones of EEVblog debunks the Solar Roadways project, which raised millions through Indiegogo and government funding. He works through the solar generation and LED power calculations to show the idea isn't viable.

Andreas Antonopoulos answers a Bitcoin Q&A question about energy consumption in mining. He argues that mining is arbitrage for the cheapest electricity, drives investment in renewables, and that the traditional financial system has hidden externalities.

Tom Scott visits Dinorwig Power Station in Wales, a pumped-storage hydro plant often called Britain's largest battery. He explains how it works and how its role has shifted from TV pickup spikes to balancing wind and solar.

A short Vox explainer on the duck curve, the shape electricity demand takes in California as solar output grows. It explains why grid operators struggle to balance supply and demand with lots of solar.

CGP Grey compares airplane boarding methods, based on an arXiv paper, and shows why the intuitive back-to-front approach is slow while random or outside-in boarding does better.

A short animated simulation comparing how Multics and Unix were developed, showing why Unix's small composable programs and pipes gave it a efficiency advantage. It frames Unix as a moonshot achievable by a small team.