"Open licensing allows others to replicate, reuse, adapt, improve, adopt, bring to scale, write about, talk about, remix, translate, digitize, redistribute and build upon what we have done." - Shuttleworth Foundation.
Open source means that the goods and knowledge for reproducing the technology (the "source") is freely accessible (open). This is very natural to permaculture practitioners who like to share ideas and experience in practical ways.
The term 'open source' is commonly applied to software which holds a shared community approach to the development, extension, and patching of software. Most open source projects have a dedicated group that moderates and directs the core software development and ensures that needed new features are being developed, bugs are being fixed, and the supporting documentation remains current.
Open source is also a development method for appropriate technology. Appropedia is an example of open-source appropriate technology. There anyone can both learn how to make and use appropriate technology free of concerns about patents. At the same time anyone can add to the collective open-source knowledge base by contributing ideas, observations, experimental data, deployment logs. The built in continuous peer-review can result in better quality, higher reliability, and more flexibility than conventional design/patenting of technologies. The free nature of the knowledge also obviously provides lower costs, particularly for those technologies that do not benefit to a large degree from scale of manufacture.
Open source also enables the end to predatory intellectual property lock-in. This is particularly important in the context of technology focused on relieving suffering in the developing world. Open sourcing allows a horizontal transfer of technology, gives greater autonomy for local communities to build the technology they need, and enables them to tap into a global knowledge base. It often gives rise to greater modularity in design (easier to fix, maintain and integrate), and thus in many cases better re-use of materials and components: leading to a cradle-to-cradle lifecycle.
There are a wide range of open source projects, from software such as Mozilla, operating systems such as Android and Linux, hardware such as Arduino, even some types of beer. There is also an increasing number of inspiring open source energy projects such as Onawi, an organisation that aims to make designs of wind turbines freely available and River Simple who have made their design for hydrogen cars open source. The open source energy monitoring project another example which empowers the user (rather than the Big Six energy providers) to be in full control of when, how and where energy data is logged.
A very exciting development is the advent of 3D printing e.g. RepRap 3D printer: a fabricator that can self replicate many of its component parts, thus the technology can be easily passed on to other communities. 3D printing is a process of making a three-dimensional solid object of virtually any shape from a digital model. Existing 3D printers can produce limb prosthetics, water system parts such as taps, tools like wrenches, pulleys and gears. Advances in the technology could allow circuit boards and other electrical items to be produced and bigger machines could in time produce items such as solar dehydrators, and pasteurisers and medical equipment.