Читать книгу Creating an Eco-Friendly Home & Workplace - Paul Hymers - Страница 38

The versatility of LEDs in fittings and locations means that they can be encased in stainless steel or brass, or waterproofed in plastic and made entirely submersible. You can light ponds, fountains and waterfalls creatively with LEDs, but even more importantly, you can run them for free with solar power. LEDs are perfect for solar powered lighting because they last for so long: they can be fitted in sealed units that are weathertight, in the knowledge that the lamps will never need to be changed. Marker lights are commonly available with solar panels (the amorphous-film type) incorporated in the lamp cover. These are ideal for defining the edges of a garden path or pond. They can be incredibly cheap, although I’ve seen plenty where the solar panel has flaked off due to the low quality of manufacture.

Security lamps that cast sufficient light across a dark corner or a doorway can be fitted with both a solar panel to power them and the usual PIR motion sensor to activate them. Because the LEDs consume such a tiny amount of electricity, the solar panel can charge up a replaceable lithium-ion battery with enough electricity to run a light for a month or two. If the sun disappears for a couple of weeks, the light won’t stop working.

The solar panels can be quite small. A single 225 mm x 150 mm monocrystalline 6 volt charging 9 volt solar panel will generate 3 watts of power for an LED lamp.

I’ve often used brick lights for illuminating outdoor steps and driveway entrances. As they come in brick size to discourage vandalism and prevent accidental damage, they can be built flush into walls, with only the lens glass and the bulb behind it left vulnerable. With LEDs, the lamps are often encased in a solid brick of acrylic, making them entirely damage resistant. LED brick lights are often 5 watts but fitted with diffusers to reduce the glare and louvres to ensure the light only shines down to the ground rather than up into your eyes. They loose some efficacy, but these are important features and they will still provide a valuable service on garden pathways and steps.