There are a number of ways in which solar lighting design solutions differ from conventional exterior lighting installations, so it is important to understand what additional information is needed and why it is required. 

The artificial lighting component can be approached in the same way it would otherwise. Once lighting levels have been determined, suitable luminaires can been selected, together with corresponding beam distributions, wattages, and locations to satisfy the design. 
However because the luminaires also have to generate their own power, additional factors need to be considered. 

  • The Project Location: City, ZIP/Post Code or installation address.
  • Lighting operation schedule and control requirements.
  • Number of autonomous days or operating hours from a full battery.
  • Availability of grid power or if luminaires must be independent.
 
The project location plays a much more important role in solar lighting design due to the myriad of external factors which influence the amount of available solar radiation for converting into electrical energy. This includes but is not limited to the average number of sun hours throughout the year, weather and climatic conditions, as well as local geography and surrounding landscape. As you can imagine, an installation near our headquarters in Bangkok, Thailand will have very different conditions to that of Factory 3 in Oregon, USA.
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Once the location is confirmed, the most suitable solar cell technology can be selected. Each location has its own “Panel Generation Factor” which will influence the design and operation calculations of the solar lighting system. Knowing how much potential energy is available, enables the remaining variables – operation schedule, control requirements, autonomous hours and availability of grid power – to determine the best possible solution. 

 

 

The operating schedule and controls are similar to a standard installation with a few additional options. The luminaires can be controlled via time clock, photoelectric cell or a combination of the two for powering on and off. Light levels can be reduced during low traffic times via automatic dimming or movement detectors, with the added possibility of controlling the output in relation to available battery power. 

 

The final panel, battery size and fitting is then determined by the number of autonomous days or operating hours needed from a full battery. The best case scenario for a solar lighting installation is to receive enough solar radiation during the day to provide power to the battery for operation at night. Due to many different factors this isn’t always possible, particularly during winter when the days are short and sun light is already in limited supply. With everything else considered, knowing how many days of operation is required on a full battery will help determine the ideal combination of solar panel, battery size and lamp wattage. 

What makes solar lighting solutions particularly unique when compared to conventional exterior lighting installations is that they are not reliant on the local utility grid. This enables solar lighting to be utilised in remote areas with very limited or without locally available power, yet still provide lighting for safety and security. 

To experience the best of both worlds, on-grid or grid tied solar energy systems have multiple sources of electricity. If the system power is drained or there isn’t enough solar radiation to produce its own electricity, power can be drawn from the local utility grid to supplement the electric lighting. Allowing the system to benefit from clean energy and reduced operating costs, with backup from the local grid to ensure the lights are always on when needed. 

Establishing LIGMAN Solar Lighting is part of our commitment to this technology. As you can see, there are many things to consider when designing and implementing a solar lighting solution, and it can be difficult to know where to start. In the same way our dedicated team has provided years of ongoing support with our main catalogue of luminaires through photometric files, schematic drawings and lighting calculations – you can now expect the same high quality service when it comes to solar lighting solutions.