Introduction to Solar LED Lights
Solar LED lights are increasingly becoming a staple ingredient of modern landscape design. Ecologically sound and arguably far more varied and attractive than traditional mains powered garden lighting, the latest generation of solar LED lights are quality products, well constructed and resilient to whatever life outdoors can throw at them.
Solar LED garden lights have many obvious uses, such as accent lighting for driveways, passages, steps and all manner of other pathways, where they obviously enhance safety and security. But solar LED lighting also has many other, less obviously functional, uses as we shall see.
The common factors shared by all solar LED lights are that they are safe, easy to install, reliable, versatile and very low energy – correction, very low renewable energy. The combination of free solar power to recharge batteries and LED light bulbs that require only a fraction of the electricity to provide the same amount of light as traditional light bulbs means that solar LED garden lights tick all the boxes where energy saving and the environment are concerned.
How to Install Solar LED Lighting
Although solar LED lighting has many obvious benefits, there are a number of points to consider before you purchase and install solar LED garden lights in order to get the best from your garden lighting system. So how good are solar garden lights exactly?.
The principal issue of course is sunlight. Solar garden lights are powered by batteries – rechargeable batteries. These last approximately as long at night as the amount of time their solar charging panel is exposed to sunlight during the day.
This is also the reason that solar garden lights tend not function so well during the winter in northern (and of course, southern) latitudes, for which there are two easy remedies. Either take the batteries out and recharge them using a regular mains battery recharger, or switch the lights off for an evening or two to allow the solar panel to fully charge the batteries without being drained overnight.
So a primary constraint is always to locate the Photovoltaic (PV) cell, as solar panels are also termed, somewhere it will get plenty of natural daylight – and for optimum performance, abundant sunlight, though even overcast conditions are sufficient to give a reasonable charge. Shade caused by trees, buildings and other obstructions will reduce the effectiveness of the daylight recharging cycle (as will a poor aspect, such as facing north in a northerly region) which will in turn reduce either or both the brightness and duration of the affected solar garden lights come the evening.
Some solar LED garden lights have an integral solar panel while others are connected to a central solar panel and battery unit. In either case, the solar panel is usually designed with a slight tilt so that it can be orientated to face the sunniest aspect of the garden. Solar garden lights that incorporate an integral solar panel are clearly much easier to install (just put it down where you want it really) but will not function so well in a shaded situation and each one has its own on/off switch which means there is no form of central control. Solar lighting that connects to a separate solar panel can be placed anywhere without regard for access to sunlight since only the solar panel needs this. You can also control a group of solar garden lights from a central location, though the downside is wires – each solar garden light now has to be connected up to the shared solar panel.
Best Batteries for Solar LED Lights
If sunlight for the solar panel to convert into electricity is the primary consideration, the second most important component in solar LED garden lighting is the battery choice.
Always check to see what type of battery is supplied when you purchase solar garden lights. Sometimes, if the supplied batteries are poor quality (see below), it’s worth sending them for immediate recycling and fitting better quality batteries which will not only greatly improve light levels and duration but last much longer.
Lead acid batteries are poor at holding a charge and have a very limited life span. Nickel Cadmium (NiCd) are better but Cadmium is a pretty toxic heavy metal and not something you want to see dumped in landfill (in many US states and European countries it is in fact a requirement that NiCd batteries be properly disposed of at waste recycling facilities).
The best of the bunch commonly available these days are Nickel Metal Hydride (NiMH) batteries which take a charge much better and have a much superior life expectancy. At 1,000 to 3,000 (as some manufacturers claim) recharge cycles, you can expect a useful life of 3 to 8 years from NiMH batteries as solar powered lighting of course runs a complete discharge/recharge cycle each day. Your solar garden lights will also look a whole lot brighter and stay bright for longer.
Always remember to dispose of rechargeable batteries responsibly; most places that sell batteries provide a bin for collecting dead ones for recycling.
If you plan to hook your solar LED lights to a central solar panel then you will likely also need to consider a deep-cycle battery suited to solar power applications.
Battery technology is very much the unsung hero behind a great many modern electrical and electronic developments and is continually advancing with Lithium Ion (Li-ion) batteries taking over from NiMH. Here’s a handy table of rechargeable battery technologies that lists their various performance characteristics.
Solar garden lighting is no different to most other things in life – you get what you pay for. Avoid the budget end of the market though and purchase only solar LED lights and quality batteries and you should be pleasantly surprised at how effective modern solar garden lighting is.
How to Mix Low Voltage Outdoor LED Lighting and Solar LED Garden Lights
For whatever reason, there is a commonly held but erroneous belief that you cannot combine low voltage LED garden lighting with solar powered LED garden lights. But in fact there is absolutely no reason not to combine the two, even within the same physical space, so long as you understand the differing characteristics of mains powered lighting and solar powered lighting, which boil down to the nature of the power source.
Battery power has two constraints: the length of time it can provide a charge and the amount of electricity it can deliver while discharging. The two are obviously related, so if there is very little load on the battery it will last longer and conversely it will discharge more quickly if running a higher load (i.e. a brighter light).
As noted above, generally speaking the rechargeable batteries found in solar garden lights are expected to discharge fully over anything up to 12 hours (though typically rather less) which effectively dictates how much power they can deliver to illuminate a bulb (or more commonly these days, an LED). The answer is usually “not very much”, so the light source found in most solar garden lights tends to be rated comfortably below 1 watt. It’s also the reason for the dominance these days of solar LED garden lights since these deliver considerably more light for the same amount of electricity and/or operate for longer as a consequence.
In other words, solar garden lighting provides ambient light rather than something you might try to read a book by. This isn’t always the case, as we shall see in a future article, but it holds true for the majority of solar garden lights found in DIY stores and garden centers. But ambient light is actually quite a desirable effect for illuminating outdoor spaces at night. Many people dismiss for example the common or garden solar LED lantern on the grounds that it’s not bright enough to illuminate its surroundings, and in so doing completely miss the point that one of the principal advantages of most solar LED lanterns is precisely the fact they provide low level ambient light.
The most effective garden and patio lighting designs mix together lighting of varying levels, beam angles and color to create a compelling night time look that is often quite different to how the garden looks during the day. Consider how your garden or deck might instead appear if you simply trained a whole series of uniform bright floodlights on it? The effect would simply be a flat, harsh, less appealing version of the day time garden with most of the color washed out.
The whole point of outdoor LED lighting is that it presents a fabulous opportunity to have a second garden – the night garden, which has its own character and is related to, but clearly distinct from, the daytime garden. You can for example enhance garden features that may not sit center stage during daylight or fool the eye and reshape certain aspects. Since the backcloth is darkness, it is relatively simple to paint a new picture onto this black canvas using light.
An easy effect to achieve using solar LED lighting is redrawing boundaries. In the absence of normal visual guides as to where your garden begins and ends, or to its overall layout, you can provide deliberately misleading spatial hints using a careful combination of low voltage LED lights and solar LED garden lighting.
For example, we expect that things closer to us will appear larger and brighter, and that the reverse holds true. This principle has been known and used by artists for several centuries in order to give the impression of 3D perspective on a two dimensional surface. By spacing relatively subdued solar LED lights beyond much brighter and bolder low voltage LED garden lights it is possible to create the illusion that the lower powered solar LED lights are much farther away than in fact they are, thereby extending the apparent depth of your garden.
Another popular garden lighting effect involves mixing the soft, ambient glow that many solar garden lanterns produce with much brighter, sharper solar LED lights. If you also opt for a mix of differently colored solar LED garden lights this can create a quite stunning visual display, with sharp spots of vibrantly colored LED light like highlight in another wise diffuse and atmospheric background.
So get stuck in, outdoor solar lighting is where it’s at where modern landscape design is concerned.