From Appropedia
Jump to: navigation, search
edit  watch  

The Transport Portal

Bicycle wheel
Transport. According to the Appropriate transport manual, sustainable transportation is a strategy for the flow of people and goods across the Earth that meets the needs of the present without compromising the ability of future generations to meet their own needs. Transportation accounted for 32.6% of US green house gas emissions in 2005. In addition to the widely publicized environmental consequences of driving automobiles, it is also socially and economically costly:
  • Land use: Parking and roads use valuable land resources.
  • Transportation equity: Driving, with all of its expenses, costs the average U.S. household $7,000 per year per vehicle.
  • Economics: Most of the money spent on driving leaves a local economy, weakening it.
  • Community: Travelers outside of their cars interact more with their physical environment and each other.
  • Safety: The presence of pedestrians and cyclists make our neighborhoods safer from crime. Conversely, 42,000 Americans are killed in car accidents every year.
  • Health: Increasingly, Americans are suffering from weight-related illnesses. This is partly attributable to the decline in active transportation use and availability.

Building and encouraging alternatives to the single-occupant vehicle, or, for short "alternative transportation," is imperative. Some alternative transportation advocates have taken to using the term, sustainable transportation, instead of the previous, widely-used "alternative transportation" term to avoid sidelining their interest from the mainstream.

Many efficient, practical, and inexpensive sustainable transportation technologies already exist, meaning activism, policy work, and planning research is most often more crucial to developing sustainable transportation than technology development.

edit  watch  

Selected page

Fixed dome digester
Biogas and liquid biofuels. Biomass residues can also be converted into various non-solid fuel forms. These fuels are referred to as biogas and liquid biofuels. The aim of this conversion process is to improve the quality, specific energy content, transportability, etc., of the raw biomass source or to capture gases which are naturally produced as biomass is micro biologically degraded or when biomass is partially combusted. Biogas is a well-established fuel for cooking and lighting in a number of countries, whilst a major motivating factor in the development of liquid biofuels has been the drive to replace petroleum fuels. In this fact sheet we will be looking at some of these fuels, their applications and the conversion technologies used to derive them.

In Europe and the United States, as well as in several developing countries, there is a move toward cultivating energy crops specifically for the production of biomass as a fuel. The potential for energy production from biomass throughout the world is enormous and as fossil-based fuels become scarcer and more expensive, as carbon emission levels are becoming of greater concern and as people realise the benefits of developing integrated energy supply options, then biomass could begin to realise its full potential as an energy source.

Biogas is produced by means of a process known as anaerobic digestion. It is a process whereby organic matter is broken down by microbiological activity and, as the name suggests, it is a process which takes place in the absence of air. It is a phenomenon that occurs naturally at the bottom of ponds and marshes and gives rise to marsh gas or methane, which is a combustible gas.

There are two common man-made technologies for obtaining biogas, the first (which is more widespread) is the fermentation of human and/or animal waste in specially designed digesters. The second is a more recently developed technology for capturing methane from municipal waste landfill sites. The scale of simple biogas plants can vary from a small household system to large commercial plants of several thousand cubic metres.

edit  watch  

Selected topics (Book)

edit  watch  

Things you can do


Appropriate technology · Built environment · Business · Construction and materials · Culture and community · Design · Energy · Energy storage · Engineering for Sustainable Development · Food and agriculture · Government supported development programs · Governments and sustainability · Green living · Greywater · Health and safety · Heat exchangers · Hybrid power systems · ICT and Education · Information technology · Learning · Medical Devices · Net Impact · Permaculture · Photovoltaics · Projects · Rainwater harvesting · Renewable energy · Service learning · Solar · Solar thermal · Sustainability · Sustainable business · Sustainable city living · Sustainable energy storage · Sustainable farm energy alternatives · Transport · Water