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Sharing knowledge to build rich, sustainable lives.

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Building a very hot parabolic solar cooker using pedal power tools.
Notice how the focus is the same for the various parabolas.
Aleiha's parabolic solar cooker. The paraboloid is an interesting shape with some amazing qualities. It has the power to concentrate light, electronic waves, sound, etc. to its focus at the center. To find the focal point of a paraboloid, one must use the formula, y=p*x^2, where p is a constant. The variable y is the depth of the dish, and x measures the distance from the center axis to the maximum circumference of the dish. You have to pretend that there is an x axis going through the center of the base of the dish and a perpendicular y-axis passing from the center of the base of the dish to the focal point. The two numbers, x and y, represent a point on the paraboloid, and from that, you are able to determine where the focus is.

Parabolic cookers have been used for centuries now. The idea to concentrate light using curved mirrors was developed by the Greeks, Aztecs, Incas, Romans and Chinese. The Incas used bronze and gold for their mirrors and they built structures that were several stories high. This technology seems to have appeared around the same time for each of the civilizations. It is thought that Archimedes harnessed the technologyW to defend Syracuse from invading Roman fleets in 212 BC.

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New Dawn composting toilet

New Dawn composting toilet at a demonstration center in Costa Rica, helping treat human waste and provide fertilizer with a reduced bacteria count.

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Community action news

Madrid Shared Space.jpg
Feb 27 Spain: El anillo ciclista que revolucionará la movilidad [1]

Feb 26 Spain: 10 propuestas sevillanas para luchar contra el cambio climático [2]

Feb 24 Chicago: And then? Sustainability Through Arts + Culture [3]

Feb 24 Sustainable transport activism: Ethical and user-friendly transportation options [4]

Feb 23 France offers €200 subsidy on electric bike purchases [5]

Read More...


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Architect Eliel Saarinen
Always design a thing by considering it in its next larger context – a chair in a room, a room in a house, a house in an environment, an environment in a city plan.

Eliel SaarinenW
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Aleiha's parabolic solar cooker
In physics, energy is an indirectly observed quantity. It is often understood as the ability a physical system has to do work on other physical systems. Since work is defined as a force acting through a distance (a length of space), energy is always equivalent to the ability to exert pulls or pushes against the basic forces of nature, along a path of a certain length.

Sustainable energy is the provision of energy that meets the needs of the present without compromising the ability of future generations to meet their needs. Sustainable energy sources are most often regarded as including all renewable energy sources, such as hydroelectricity, solar energy and power, wind power, wave power, geothermal energy and power, biomass fuel and energy, and tidal power. It usually also includes technologies that improve energy efficiency.

While many renewable energy projects are large-scale, renewable technologies are also suited to rural and remote areas, where energy is often crucial in human development. As of 2011, small solar photovoltaic (PV) systems provide electricity to a few million households, and micro-hydro configured into mini-grids serves many more. Over 44 million households use biogas made in household-scale digesters for lighting and/or cooking, and more than 166 million households rely on a new generation of more-efficient biomass cookstoves.

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ENGR 215 Introduction to Design projects – Spring 2012: Friends of the Dunes: The Spring 2012 semester of Engineering 215 worked with Friends of the Dunes to design and build projects that support the Humboldt Coastal Nature Center at 220 Stamps Lane, Manila, CA.

Spring 2012 ENGR 215 Intro to Design Projects - Humboldt Coastal Nature Center
Solar Powered Trail Lighting System
Solar trail lighting  
Carbon Footprint Wheel
Educational carbon footprint display  
Living Green Roof
Green roof educational model  
Acoustic Panels
Acoustic panels utilizing re-purposed materials  
Living Green Display
Interactive display promoting environmental consciousness  
Rapid Composter
Rapid composting system  
The Stretchbarrow
Hybrid stretcher/wheelbarrow  
The Sandy Cove
Amphitheater constructed of urbanite  
Pump Powered Dune Movement Simulator
Interactive sand dune model  
Beachgrass Baler
Tool to bale beach grass  
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Energy

Solar
Water
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