pump drill

Primitive Technology shows building a cord drill from scratch and then upgrading it to a pump drill, using only primitive materials like a stone flywheel and cord.

Technology Connections explains why heat pumps matter right now, covering their efficiency, how they hold up in cold weather and the energy savings over burning fuel. It follows his earlier explainer on how they work.

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.

A very long, detailed look at the A4/V2 rocket turbopump, the steam-turbine-driven twin propellant pump system. It covers the peroxide and permanganate catalysis that drives the turbine. This is part 1 of a series on V2 components.

Rick Roderick's 1993 lecture on Baudrillard, the last in his series The Self Under Siege. It covers hyperreality, simulation and what Baudrillard calls fatal strategies.

A UK tradesman's rant on the disadvantages of air source heat pumps, covering grants, heat pump types and whether they are worth it. He argues they are impractical for many British homes.

Technology Connections explains how heat pumps work as reversed air conditioners and why they can deliver several times the heat of resistive heating per unit of energy. It also tackles common myths such as poor cold-weather performance.

A Technology Connections video on how ground-source (geothermal) heat pumps work and why they hold efficiency in winter. It also covers related heat pump information, and the description notes air-source heat pumps have since improved.

Technology Connections' long closing video in his heat pump series, arguing that adopting heat pumps is well within reach. It explains how they work and what it takes to start using them.

Philosopher Daniel Dennett visits Google to discuss his book Intuition Pumps and Other Tools for Thinking, describing thought experiments and thinking tools across psychology, biology, computer science and physics.

A short documentary about the 1980 Lake Peigneur accident in Louisiana, where an oil rig drilled into a salt mine beneath the lake. The lake drained into the mine, creating a whirlpool that swallowed barges.

Tom Scott explains how decades of deep coal mining sank parts of Germany's Ruhr Valley and changed its drainage. Pumps run by Emschergenossenschaft must now work permanently to keep towns and cities from flooding.

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.

Matt Parker of Stand-up Maths examines the Texas Supreme Court filing claiming Biden's 2020 win had a one-in-a-quadrillion chance. He walks through why the statistical argument is flawed.

Scott Manley explains the plumbing of rocket engines, including pressure-fed, gas generator, expander and staged combustion cycles. He shows why more complex designs exist and what they gain.

A Primitive Technology episode in which the creator builds a bow-drill-driven bark fan to blow air into a fire, using only natural materials. It shows the progression from fanning a fire by hand to a rotary forge blower.

Quint BUILDs tests a rooftop water storage setup in which solar power pumps water up to the roof and a turbine generates power later. He works through the numbers to show how much energy it actually stores.

Munro Live's Model Y episode 36 has Sandy Munro walk through the disassembled Tesla Octovalve and heat pump system. He explains how the components are made and what each one does.

Technology Connections explains in 33 minutes why thermoelectric (Peltier) cooling is far less efficient than compressor-based refrigeration.

Technology Connections explains how refrigerator and freezer design affects energy use, using chest freezers to show why top-opening designs and layout choices matter. It includes thermal-camera footage of cold air spilling out of upright units.

A 27c3 talk on the Linux desktop (GNOME) by Wolfgang Draxinger, repeatedly interrupted and corrected by Lennart Poettering from the audience. The description notes much of the talk's content is disputed.

A five-minute lightning demo of VisiData, a terminal tool for exploring and manipulating data. It uses two months of NYC 311 complaint data to drill down, plot points on a virtual map and save selected rows.

Technology Connections explains how the simple American drip coffee maker works, including the bimetal valve and bubble-pump heating, and compares the original Mr. Coffee with modern machines.

Veritasium explains how trees lift water from roots to the top of tall trunks, using transpiration pull and the negative pressure that liquid water can sustain. It explains why trees do not need pumps or valves.

A short Harvard Online animated lesson on how the mitochondrial electron transport chain works. It shows proton pumping and the machinery that drives ATP synthesis.

Tech Ingredients explains the principles of magnetohydrodynamics and builds several demonstrations, including propelling liquid metal and electrolytes with magnets and a railgun-style setup.

Adam Savage and engineer Kipp Bradford build a compact wearable refrigeration system to keep Adam cool under costumes, modeled on the cooling unit in a NASA spacesuit simulator. It is a long, hands-on build session.