An Introduction To Outdoor Solar Lighting
Most folk are by now familiar with solar garden lights of course, and you may even have spotted solar powered street lights and highway signage.
So how might you want to use solar lighting more extensively around your home and garden? The most obvious candidate to start with if you’re new to solar lighting would be lighting for an outbuilding such as a garage or shed. Installing outdoor solar lights for this purpose is simplicity itself and not particularly expensive either.
Among the advantages that low voltage outdoor solar lighting has to offer are that it is lightweight, there are few wires and cables to trail around, and being low voltage it’s safe to handle which also means that outdoor solar lighting is exempt from Building Regulations and therefore you don’t need to be (or pay for) a qualified electrician to install it. But it’s not all sunshine and roses in the garden and here’s a summary of their pros and cons to help answer that perennial question: are solar garden lights any good?
The principal advantages of solar garden lights:
- They’re ridiculously easy to setup. No wiring or protecting cables in the ground – simply position the units where you want it and wait for nightfall. And if you’re not happy with the layout, just move it all round again.
- Cost. Solar garden lights cost slightly more to buy than regular outdoor lighting but the total cost of ownership is much less, because they cost almost nothing to run (there’s still the cost of replacing rechargeable batteries occasionally)
- Very low maintenance. There is almost nothing required other than perhaps to brush leaves or snow off the solar panels and periodically replace the rechargeable batteries.
- Reliable and very safe.
- They’re amazingly versatile in terms of potential applications and the range of styles and formats to choose from is enormous.
The downsides of solar garden lights:
- They really do need plenty of sunshine and if you can’t guarantee it you won’t get optimal performance. You also need to ensure the solar panels are kept free of leaves, snow and other debris
- The batteries don’t last forever. All rechargeable batteries specify a maximum number of charges they will take before they become ineffective, which means there is at least some maintenance, waste and cost involved
- They’re not as bright as main electricity powered outdoor lights and they can’t stay fully illuminated for as long since they rely on a single battery charge
- With very few exceptions and/or extensive modifications they cannot be switched on and off at will and/or as a group since each solar light unit invariably has it’s own solar panel/battery power supply controlled by an automatic light level meter
Solar Shed Lighting
Solar shed lights can be sourced online in kit form for as little as just under £20 in the UK for example (about 30 US dollars or 25 euros). This most basic solution would power an 8w super bright LED lamp (actually a cluster of 5 separate LEDs that provide lighting equivalent to a regular mains powered 40w bulb) for slightly over four hours each evening. Easily ample for many tasks that might be carried out in a shed.
You can even go one step further and install a solar laptop charger kit. Given the range of wireless networks these days, you could quite easily set yourself up a perfectly functional office or study in a shed or summerhouse, complete with lighting, heating and electrical supply for recharging items such as a laptop computer.
This basic idea can quite easily be scaled up, so a solar shed lighting system costing at the moment slightly over £400 is more that capable of providing between 8 (in winter) and 11 (summer) hours of mains quality lighting each day (equivalent to about six 40w bulbs) – even in a gloomy Northern Hemisphere place like the UK. This is more than adequate for lighting a garage or workshop, let alone a shed, summerhouse, playhouse, greenhouse or similar small domestic garden outbuilding.
In practice of course, most people don’t switch lights on in workshops and garages for over 8 hours a day, so this sort of system has ample spare capacity to power many low voltage tools, recharge 12v batteries and so forth.
Batteries for Storing Solar Power
In the examples above of outdoor solar lighting, the suggested prices include the cost of the photovoltaic cells (solar panels) and low energy lights but do not include the cost of the workhorse behind all solar lighting: batteries. In the first (cheapest) case the system can easily be powered by normal AA rechargeable batteries, for which check this discussion of the best batteries for solar lights.
For the scaled up version you would need a deep cycle battery. There are several different types of batteries suitable for solar power systems, but all have the characteristics that they can be charged over a lengthy period with a relatively low current, deliver a consistent voltage and, as the name suggests, tolerate being almost fully discharged over many cycles.
It is possible to get away with using an ordinary car battery for power storage, especially if you install ultra low energy LED lights and/or don’t place extreme demands on your solar lighting system. But you should try to ensure that any car battery is never discharged below 50% of its capacity otherwise it is likely to be permanently ruined.
For anything other than a simple solar shed lighting kit therefore, you really should make a long term investment in deep cycle batteries, especially if you plan on extending your solar home lighting indoors.
A Solar Powered Greenhouse
Of course, all greenhouses are “solar powered” – that’s the point of them; the “greenhouse” effect is well known as a metaphor for global warming because a greenhouse traps heat inside the glass during the day thereby raising the temperature and hopefully storing some heat to protect tender plants overnight as the outside temperature drops.
But sometimes the sun is not enough. Greenhouses actually need “sunshine” as opposed to just daylight, whereas photovoltaic (PV) solar panels will function in ambient light conditions. Also, no matter how warm your greenhouse gets throughout the day, none of this helps you see what you’re doing in there once the sun goes down.
A simple outdoor solar lighting kit of the sort intended for a shed or workshop will easily power electrical greenhouse heaters to maintain temperatures, even through the short and typically overcast days of winter. Once installed, a solar powered greenhouse system will go on providing free power for literally decades and you may amuse yourself by dreaming up ever more uses for that free, low voltage power. It can be used to provide workable lighting to extend the time you can make use of your greenhouse; operate electrically powered vents and/or run fans to ensure a constant temperature inside the greenhouse; control automatic watering systems and so on.
Portable Outdoor Solar Lighting Applications
The characteristics of outdoor solar lighting – lightweight, robust, self-contained – also make it ideal for portable lighting applications, i.e. installing it in things that move such as caravans, motor homes, boats, and for camping expeditions.
All large vehicles such as caravans and motor homes have a sizable amount of redundant surface area pointing straight up at the sun, namely the roof. Affixing a solar panel to the roof of such a vehicle is such an obvious move – why waste all that potential free electricity just sitting there on a part of the vehicle no-one even sees unless they’re up a ladder washing it.
Install some camper solar panels and whenever you go away you have the power to run all the normal comforts of life such as TV, computer, fridge etc as well as abundant lighting and it neither costs a dime to run nor creates pollution and CO2 emissions, as would be the case using a regular generator.
Of course, pretty much the same applies to boats (the sort you can sleep in and go places, not rowing boats, obviously). There is usually some amount of unused space on the deck or above the cabin where solar panels can be installed. Boats can also take advantage of a second form of free renewable energy: wind turbines, but that’s a topic for another time.
Some Unusual Uses For Outdoor Solar Power
As well as powering lights, outdoor solar power can be used to run a variety of devices that would otherwise be awkward to route power to.
For example, got a problem with moles (or gophers if you live in the USA) then how about installing a solar mole repellent? These can be stuck into the ground wherever required (they typically cover about 6000 square feet of territory) and emit an ultrasonic pulse which burrowing pests such as moles and gophers find unpleasant will avoid. It’s effective, humane, portable and free to operate.
Other garden pests than can ruin an otherwise pleasant evening include biting flies, mosquitoes and irritating midges. But you can say goodbye to annoying insects with a solar powered bug zapper that will go on attracting and dispatching these nuisances long after the sun goes down, night after night.
Running a business from your home or have some other other reason to ensure that folk know where to find you? Solar powered outdoor sign lighting could be just the thing you need.
Another unusual application is solar stepping stones – these are just like ordinary stepping stones, decorative paving slabs that mark out a pathway, but include an integral solar powered light so you can see where you’re going at night.
Similarly, many garden ornaments such as small fountains, birdbaths and sculptural features such as obelisks and the like, can either now be purchased with integral solar lighting of retro-fitted so as to add another dimension to the garden at night. And of course, fountains like many other small water features can have their water pumps powered by discreet solar panels.
Got an awkward security problem, then how about installing a solar CCTV camera? These are usually wireless CCTV cameras (also often called network or IP cameras) that have low power requirements, only capture images when movement is detected and don’t need cables since they send images directly to a wireless router. Solar CCTV cameras are worth considering as part of any home surveillance system and have the added advantage that they can upload images directly to the internet and store them on some web space or transmit them to your email or phone inbox which also therefore provides an integral alert system.
Scaling Up With Outdoor Solar Lights
In principle, and indeed in practice, scaling up an outdoor solar lighting system is simply a matter of adding more of the one or several of the three essential components: solar panels, storage batteries and low energy lights (preferably LED).
If you want more light then add more light bulbs; if you need more power to run the lights then add more (or larger) batteries; if you need more electricity to charge the batteries then add more (or larger) solar panels. That’s about as complicated as outdoor solar lighting gets.