Tools and technology (Appropriate technology)(6m 56s)
The principle for the appropriate technology chapter is to increase energy efficiency. In this chapter, we’ll talk about making charcoal, hand tools, machines, motors, electricity. Some basic and useful technologies that make our life easier and help us become more energy independent.
Heat
Okay, we’ll start with fire, one of the most basic, forms of technology. One of the first things we learned about the point, was that if we blew it up – it would quickly produce heat, cook food, leave carbon, among many other things.
What is bio-char?
Biochar is activated charcoal, a highly-porous. This charcoal is produced using pyrolosis, a process of decomposing wood into carbon under extremely high temperatures. You can tell if charcoal is bio-char if it clinks like glass when you handle it.
Bio-char is carbon negative, meaning it pulls carbon from the air and stores it in the soil. 1 gram of bio-char, the size of a pencil eraser, has about 9000 square feet of surface area. This is the area of almost two football fields.
So it has an unusual amount of surface area, which provides space for bacteria to latch on to in the soil. This charcoal is made using the pyrolysis. The process of decomposing wood into carbon under extremely high temperatures. You can tell if the charcoal is biochar if it clinks like glass when you handle it. Biochar is carbon negative, meaning it pulls carbon from the air and stores it in the soil.
How to make a bio-char
One method for making bio-char uses 1 and ½ 200-liter metal drums, a steel pipe for a chimney. Any type of wood will make charcoal – the denser the better. Make sure you seal the drum using mud after burning or else the charcoal will smolder into white ash. For step-by-step instructions on how to make a bio-char maker, watch this excellent video by Pun Pun Center for Self-Reliance in Thailand.
Heat – Wood vinegar/charcoal maker
Wood vinegar is an insecticide useful for keeping pests away. It also eliminates odors from Humanure poo chambers. It smells like an oaky wood fire. Wood vinegar burns at a much lower temperature than bio-char. So the charcoal produced isn’t as porous and is better used for barbequing.
200 liters of wood produces about 10L of vinegar. You can dilute with water about 100:1 (water: vinegar) to get more use out of each batch.
Hand tools
A hand tool is a tool, which only requires human power. Most communities around the world have access to basic hardware stores where simple hand tools like shovels, hoes, picks and trowels and materials like pvc water pipes, cement, tin roof panels, 200L barrels, 20L buckets … basic things can be found.
Using the right hand tools for any job can get you where you want to go, faster. Examples of hand tools include: Hoe, shovel, pick-axe, machete, buckets (large and small), rake, handsaw, axe, secretors, box cutters/pocket knife, hammer/nails, wire cutters, pitchfork, garden fork, earth tamper, vice, measuring tape, steel rod, the list goes on.
Simple machines
There are six simple machines, the lever, the wheel and axle, the pulley, inclined plane, the wedge and the screw. These six movements can be regarded as the elementary “building blocks” of which, all more complicated or compound machines, are composed. Greek philosopher Archimedes, as well as scientists Galileo and Leonardo da Vinci, each made contributions to these machines during that era.
Experimenting with these basic movements can help move heavy loads, perform other tasks and provide a good foundation to build more complex and advanced machines. It all starts with these basic movements. Here are brief descriptions of each of them:
Ramp – Inclined line with a circle on top
An inclined plane is a ramp. It has a slanted surface and helps you move things from lower to higher places. Moving something up a ramp takes less force. A handicap ramp is a good example. .
Lever – Line with circle underneath
A lever is a line with a point. Place a load on one end and use force on the other. The force lifts the load. Example: Seesaw, scissors. Here’s a video demonstrating a level machine lifting bricks: http://www.youtube.com/watch?v=8a9adBsGYDk (watch at 10:30).
Screw – Line, with another line moving in a circle
A screw is an inclined plane wrapped around a column. Screws are used to attach things together, can be used to draw water from a well attach two pieces of wood together. A wood screw is an example.
Wedge – Three lines, forming a triangle. A wedge is two inclined planes. It has a tapered end and a wide end. It is used to cut or split objects. Example: Axe.
Pulley – Circle or multiple circles with one line. A pulley changes the direction of the force. A pulley consists of rope and a wheel. When you pull the rope, it lifts the load. Example: Flagpole.
Wheel and axle – Circle with line coming out of the center, attached to other circles and lines. A wheel turns around a center rod that is called an axle. A wheel and axle is actually a lever that turns. Wheels make our work easy because they roll. Example: wheel.
Simple movement – motion
Bicycle power
Speaking of wheel and axle, a bicycle, two wheel and axles attached by a pulley, can be modified to pump water, sift sand, wash clothes, blend or charge cell phones and laptops. Bicycles are very useful, versatile things.
Compound machines – Motor
Power tools
Machine tools operate using electricity or a generator. Examples of machine tools include a drill, circular saw, grinder, wood chipper, cement mixer, chainsaw, welding machine, generator, electric sander.
Heavy machinery includes large equipment that can do more work because of their larger size. They usually require gasoline or other consumable fuels. Renting or using heavy machinery can save time and labor. Useful examples include excavators, Bulldozers, Cranes, Graders, Hydraulic tampers, Grain grinders, other food-processing equipment.
Electrical power
Wind turbines use the wind to turn large propeller attached to a gearbox, which spin a rotor, that fits inside of a stator, a stationary box, leaving just the smallest amount of space between the two. The rotor and the stator are each packed with high-powered magnets and wrapped with copper coil.
Imagine the rotor spinning real fast, and in this tiny space between the magnets, the magnetic attraction moves back and forth… choo choo choo cho chhhchchchchch, it moves so fast it creates a charge, a point… now imagine dropping in a highly conductive copper wire, and bwoooooh, the energy is gone, soaked up by the copper wire and blasted into someone’s toaster 15 miles away. We make lightning and use it to toast bread. We are gods.
Quick recap of this chapter, we’ve had a long evolution, we’ve been using this imaginary point in front of us to do many things. You can use it to make charcoal, and there are some very basic things we can do to help lift loads, do things in general. And then, you know let’s explore this renewable energy. This stuff is the future. We can be energy independent.
Okay for our site designs, this is a broad topic, but think about how we can make charcoal, use simple tools and machines, create electricity and consider other ways to make your site more energy efficient. Okay, that’s it for the appropriate technology chapter. Thank you for your time.