A Passively Cooled House in the Tropics

passive house tropics

Build-It-Solar blog writes:

Kotaro Nishiki built a passively cooled home in Leyte Philippines at 11 degs north latitude that incorporates a number of unique cooling features that allow the home to be cooled passively and without electricity…

In this area, most homes are constructed of concrete, and the concrete structures tend to absorb solar heat during the daytime, and then retain that heat through the night making the homes uncomfortable.

Kotaro’s design is centered on eliminating these daytime solar gains. He keeps the whole house shaded using these techniques:

  • The south facing single slope roof has on overhang on the south that keeps the south wall in shade most of the day.
  • The north side of the house is shaded by an roof extension sloped down to the north that shades the north side of the house most of the day.
  • The roof is double layered with airflow between the well spaced layers.  This greatly reduces solar heat gain through the roof.
  • The east and west walls of the house are double wall construction with a couple feet between the walls.  The shading that the outer wall offers plus airflow between the double walls keep the wall temperatures low.
  • In addition, he has worked out ways to take advantage of the night
    temperature drop and to use thermal mass on the basement to provide some
    cooling.

More: A unique, passively cooled home in the Tropics (Build-It-Solar), Passive Solar House in Tropical Areas (Kotaro Nishiki). Build-It-Solar has more examples of passively cooled houses.

Handcarts on Rails

Looking for an even more efficient cargo vehicle than a Chinese wheelbarrow? Try a handcart on rails. The light railway shown on the pictures below was built during the early 20th century in Ghana, then a British Colony called Gold Coast. The human powered railway was used for conveying cocoa from the factory in Akuse to the river barges on the Valta river.

hand carts on rails

hand carts on rails 2

Source: EngRailHistory.

Modular Smartphones

Phonebloks is a modular smartphone that’s designed to outlast the throwaway phones of today. Previously: How to make everything ourselves: open modular hardware.

Bike-Powered Treehouse Elevator

bike-powered-treehouse-elevator

Ethan Schlussler of Sandpoint, Idaho, built this clever bicycle-powered treehouse elevator to make it easier to reach his nearly 30-foot-high treehouse. “I got tired of climbing a ladder six and a half million times a day, so I made a bicycle powered elevator to solve this problem,” he writes. See and read more at Make. More pedal powered machines.

High-tech Solar Cooker

“Instead of a big solar oven that adapts to our conventional idea of cooking, The GoSun requires a bit of adaptation of our diet. But that really is a feature, not a bug; it can be a healthier diet with less food waste.” Read more: GoSun stove reinvents solar cooking.

Water-Powered Fire Alarm

reliable water powered sprinkler alarmMid-nineteenth century, water motors operated by tap water became a valuable power source in addition to hand and foot powered machines. Most of these small-scale water motors for indoor use were Pelton turbines, which are up to 90% efficient regardless of their size.

A demonstration of how water power may be used efficiently even on a very small scale is the water-powered fire alarm. The device is still for sale today. Buildings protected by sprinkler systems often have outside alarm bells that are activated by very small Pelton turbines on the other side of the wall.

The hydro-mechanical device signals the flow of water in an automatic sprinkler system. The main flow of water lifts a valve that sends a small amount of water to the little turbine, sounding the bell. The great advantage for fire protection is that the system works independent of electricity.

Picture: a water-powered fire alarm. Source: The Reliable Automatic Sprinkler Co. Via The Museum of Retrotechnology.