Active and Passive Solar Home
Solar technology is an important renewable source of energy which can be implemented through various means. Solar homes are viable options for the same. Other solar technologies can be integrated while building a house to harness solar power benefits for various purposes.
The implementation of solar homes can be through either passive or active means. Both are effective and productive. The key difference between the two is how the solar energy is utilized. In active home, the solar energy is used for various purposes using mechanical equipments / tools - e.g. to heat water, there would be a pump which will put the water in pipes running through solar panels for heating etc. Thus, this kind of solar house requires assistance from mechanical / electrical equipments / machines for conversion of solar energy into useful energy.
On the other hand passive solar homes do not use any such things, they depend lot on "design principles" such as color, orientations, shades, glaze, etc. to trap and use solar energy. Passive solar homes are lesser dependent on the technology and more sustainable.
There are also the hybrid means of technology which are a little different from the above two and can be implemented judiciously. Solar lighting is an example of such means.
Active Solar homes
Active solar homes use technologies like solar panels, solar heat collectors and solar cells. Active solar homes convert solar energy directly to electricity or heat.
The major difference between active and passive is mainly that active sources usually apply mechanical or electrical equipment for this conversion. Therefore active sources mainly require more equipment but are majorly reliable and much more productive.
A major advantage that Active sources enjoy is that the technology can be controlled according to the users’ needs and the changing climates. This helps in maximizing effectiveness.
Also the active technologies can be easily manipulated and switched on or off according to the users’ needs. These technologies are external to the home. Active solar technologies are clean and reliably efficient sources of solar power.
Major disadvantages of active solar homes include higher maintenance than the passive ones. Also the external power related to the device is prone to failure. Especially the devices are exposed to the environment leading to more servicing requirements.
Passive Solar Homes
In passive solar homes surfaces like walls, windows, doors and floors are used while the solar energy is collected. They attract solar heat in winters and reject it in summers. Passive solar homes majorly use the local climatic conditions to provide the solar power. Unlike active technologies there are no externally connected solar devices.
These technologies have lower maintenance and are more durable than the active devices. The basic working principles of conduction, convection and radiations are used for the hat trapping mechanisms in passive solar homes. Moreover once implemented these technologies only depend on the local climatic conditions for proper working.
Proper designing with implementation of other resources like glazing, shading, compact windows for avoiding air infiltration are key issues to be considered by the user.
Solar water heaters, solar cookers, solar chimneys and in general solar homes having favorable architecture are some of the examples of passive solar homes.
Major disadvantage of the passive solar heating is that the technology is overly dependent on the climate. If the climate is not suitable for the trapping heat then the passive means are less effective than the active solar technological means. Moreover the technology cannot be optimized for user’s needs once the implementation has been done.
Also false implementation can lead to a rapid decrease in the amount of solar power being generated by the system.
Passive solar technologies are inherently dependent on the local climate and major emphasis is on the need to optimize benefits. Whereas the active solar technologies are much more technical based and equipment oriented.
Solar Home : Options available
A blend of both active and passive solar homes is recommended for the architecture of the solar homes. While passive solar technologies are relatively easier to manage they should be used only if the climate of the region permits. They should be implemented in the region between the two tropics where there is ample of solar power available. Implementing passive solar technologies at places where there is low solar energy available leads to decrease in productivity. They are therefore not recommended for use.
Active solar technologies are more viable to use in diverse climatic conditions as there is an opportunity to optimize. Moreover there are second chances for the user to optimize unlike the passive solar technologies. Active solar technologies are more technologically oriented. Though they serve for a long period they are lesser durable than the passive technologies.
Using technologies like solar pool heating, solar air conditioning through implementation via solar panels and solar cells are technologies which are viable and efficient for a variety of users. Along with these, solar chimneys and solar cookers can be easily implemented. Other solar techniques like implementing passive solar homes through glazing, shading and coloring can be used only at the time of designing the home.
Therefore it is important for the user to implement solar technology at the primary stage of building the home. Then there are other ways as well of implementing technologies as well in solar homes which can be duly used.
Summing it all up..
Using solar technologies active or passive is hugely beneficial for the users. Solar homes are the right base for using the solar technologies. They can be used for a variety of purposes saving utility costs and maintenance problems.
Active solar technologies are technically more advanced than passive technologies. They can be made increasingly productive and should therefore be implemented for majority of climates. Passive solar technologies are more dependent on the climate surrounding the area and are therefore beneficial only when there is a supporting climate to the technology. However, once implemented they are productive for many years to come. Moreover they are easy to use with least amount of manual working required.