Iluminación
La iluminación es el uso más común de un sistema FV autónomo. Elegir el tipo correcto de iluminación no solo es importante para garantizar que un sistema funcione correctamente, sino también para asegurarse de que quien esté usando el sistema esté satisfecho, ya que el tipo de iluminación, brillo y color pueden tener un impacto dramático en la experiencia del usuario. Hay tres tipos de bombillas que se encuentran comúnmente en el mercado:
- Diodo emisor de luz (LED): este diseño utiliza lo que se llama un diodo que crea luz cuando la corriente eléctrica pasa a través de él. La iluminación LED es la única opción adecuada para uso en un sistema FV autónomo. Iluminación LED, ya que es mucho más eficiente y duradera que sus predecesoras: incandescentes (bombillas tradicionales) y lámparas fluorescentes compactas (CFL). Las bombillas LED cuestan un poco más que estas otras dos opciones inicialmente, pero son más baratas cuando se considera su vida útil más larga, sin mencionar la importancia de que su consumo reducido contribuye a reducir el tamaño del PV source y el sistema de almacenamiento de energía. Las reducciones en el costo de la iluminación LED, así como las reducciones en el costo de los módulos FV, han contribuido a aumentar la accesibilidad de los sistemas FV para las personas de zonas rurales que carecen de electricidad. Comúnmente disponible en corriente alterna (CA) y corriente continua (CC).
- Compact fluorescent lamp (CFL) - this design creates light as current passes through a gas filled glass tube. These bulbs contain mercury - a hazardous element - which requires special recycling facilities. If found in remote areas, these bulbs should be returned to a proper electronics waste recycling facility. CFL bulbs should not be used with off-grid PV systems.
- Incandescent – The original lightbulb design. It creates light by passing current through a thin wire filament. Incandescent bulbs should not be used with off-grid PV systems due to their high inefficiency.
Characteristics
LED lighting is the right choice for off-grid applications, but it is important to distinguish between the different designs to ensure that there is a clear understanding of the advantages and to highlight the important role that energy efficiency plays in PV system design.
Output
Higher energy consumption for a particular lighting design (LED, CFL, incandescent) will translate into improve light output, but a 40 W incandescent bulb will produce less light than a 10 W LED lightbulb. This is because the LED bulb can more efficiently turn energy into light than an incandescent bulb which loses a significant amount of energy in the form of heat. Lumens are the proper unit of measurement for determining the brightness of a light source – a higher lumen rating means a brighter light.
| 200 lumens | 400 lumens | 700 lumens | 900 lumens | |
|---|---|---|---|---|
| LED | 4 W | 6 W | 10 W | 13 W |
| CFL | 6 W | 9 W | 12 W | 15 W |
| Incandescent | 25 W | 40 W | 60 W | 75 W |
Lifespan
LED lights last far longer than CFL or incandescent lights.[1]
| Lifespan (hours) | |
|---|---|
| LED | 25,000 - 35,000 |
| CFL | 10,000 - 15,000 |
| Incandescent | 750-1,500 |
Color temperature
Different light sources (the sun, candles, different light bulb types) emit light of different colors. A candle emits a soft yellow light that is pleasing to many people whereas the light from the sun can be quite white and harsh. The color of visible light can be classified using a measurement called Kelvin - a higher Kelvin rating means a whiter light. Different lighting products will use Kelvin to classify the color of the light that they will emit.[2] In addition to considering what color of light may be most appropriate for a given application (home, clinic, community meeting hall), different cultures have varying lighting color preferences that should be taken into account. Thankfully For the same brand and model of LED lightbulb there are often various color choices to choose from.
| Color temperature (Kelvin) | Source |
|---|---|
| 1850 K | Candle flame, sunset/sunrise |
| 2400 K | Standard incandescent lamps |
| 2550 K | Soft white incandescent lamps |
| 2700 K | "Soft white" CFL and LED |
| 3000 K | Warm white CFL and LED |
| 5000 K | Horizon daylight |
| 5000 K | Tubular fluorescent lamps or cool white / daylight CFL |
| 6000 K | Vertical daylight, electronic flash |
| 6500 K | Daylight, overcast |
Notes/references
- ↑ Green America - CFLs vs. LEDs: The Better Bulbs https://www.greenamerica.org/green-living/cfls-vs-leds-better-bulbs
- ↑ Wikipedia - Color temperature https://en.wikipedia.org/wiki/Color_temperature
