Man Retrofits Freezer to Make an Ultra-Efficient Fridge. An off-grid experimenter in Australia, Tom Chalko, has retrofitted a chest freezer to create a fridge that uses only 100 watt-hours (0.1 kWh) per day!
Why a chest freezer? Tom points out that vertical door refrigerators are inherently inefficient. Smallest Man-made Orange.
Engineering. DIY. Bicycle Power Calculator. BikeDynamics - Bike Fitting Specialists - Fit Guidelines. Chainless Bicycle Uses Wire and Pulley System, Eliminating Grease and Increasing Cool Factor. A Hungarian design team has unveiled a new chainless bike, powered by steel wires, that easily disassembles and can be organized for touring or racing.
The "Stringbike" uses two steel cables attached to pulleys, which move on swinging kidney-shaped discs as you pedal. The discs replace a traditional round gear system, and you can install different discs depending on your needs, according to the Web site Hungarian Ambiance. The position of the pedals determines the position of the discs, so that they swing in opposition — one is always pulling the bike forward, and the other lags behind. This allows a continuous transmission change, which could help a rider navigate winding streets, because you can more easily control the transmission without having to shift gears. This video demonstrates the concept.