Outdoor LED lights
An energy efficient way to light up a garden, deck, or walkway
Outdoor LED lights can help you save energy by providing exterior lighting that consumes very little energy. But before you go stocking up on solar-powered LED landscape lights or LED security lights, you should first think about the product life cycle energy costs of what you are buying, and how much you really need the outdoor lighting.
You might think it's environmentally friendly to light up your back yard with outdoor LED lights. But don't forget that it's more environmentally friendly to not light up the back yard at all. Energy is used to manufacture outdoor LED lights, ship them to the store or warehouse, get them to your home, and ultimately to dispose of them when they stop working. And if you go for cheap over quality, the disposing will happen sooner rather than later.
If you're going to light up your back yard so that it looks pretty for the ten seconds each evening that you glance out at it, you might want to do a cost-benefit analysis. And as for security lighting, did you know that having security lights on all the time not only causes light pollution (for those of us inclined to gaze at the stars) but can actually make it easier for someone to break into your home?
Main types of outdoor LED lights
We can divide outdoor LED lights according to their power source, their voltage, and their purpose.
Power source: You can install solar-powered outdoor LED lights simply by driving LED landscape lights into the ground along a garden pathway, or putting a solar-powered security light up in a driveway or by a porch. Grid-connected outdoor LED lights are a bit more complicated to install but since outdoor LED lights draw so little power, the energy costs are minimal and you won't need to worry about a steady supply of sunlight to charge solar batteries, or the batteries' tendency to weaken over time. Finally, battery-powered LED lights are great for some situations because LEDs use so little power that, even with a small, disposable battery (or rechargeable standard-size battery), you'll get hundreds of hours of use out of the light on one battery or one charge.
Voltage: For solar-powered outdoor LED lights you generally don't worry about the voltage because most of these come as standalone units or kits that take care of voltage for you. For grid-connected systems, typical voltages are 120V and 12V. 12 volt LED lights were once the most popular form of outdoor LED lighting but you can now buy most grid-connecting outdoor LED lights in 120V configurations, and because these are simpler to install the 12V outdoor LED lights are falling out of favor. But a solar-powered outdoor lighting system of your own design will be easier to manage if you keep it to 12V DC rather than 120V AC.
Purpose: What do you need the outdoor LED lights for? There are three main reasons for outdoor LED lights: security, safety/utility, and setting.
- Security LED lights are typically motion-activated, mounted on outside walls to light up a driveway, doorway, or other area where you might want the light to scare away intruders (or help a visitor find their way to your entrance).
- Safety/utility lights are any lights that help you make safe and effective use of outdoor areas. For example, LED flood lights can be used to light up a garden or yard for evening dining, and a solar-powered LED shed light helps you light up a dark shed without having to run wiring to it from the house.
- Outdoor LED lights for creating a setting or mood can be low-intensity ground-level outdoor LED lights that light up a garden path or border, particular trees or plants, or other pleasant features of your outdoor space. Or they can be LED rope lights or strings of individual light bulbs strung along a fence, garden border, or the branches of a tree. I would put LED Christmas lights in this 'setting' category too: they create ambiance but they aren't really functional. Why does this distinction matter? Because, if you're serious about saving energy, as many visitors to this website are, you have to factor in the full environmental cost of outdoor LED lights used for setting - manufacture, shipping, disposal - and decide if all that is worth what the setting provides.
More on power source
Solar power is one obvious power source for outdoor LED Lights.
One of the best energy saving features of outdoor LED lights is that you can use free solar power. There are plenty of inexpensive products that combine a solar panel, a battery, and outdoor LED lights so that sunlight captured during the day is released at night.
You have probably seen many a garden with the old-style incandescent or fluorescent solar landscape lights, typically green or stainless steel plated. They consist of a stake you shove in the ground, a lamp above, and a very small, cheap-looking photovoltaic module on the top. They also typically throw off very little light, and only early in the evening. Why is this? There are actually three reasons:
- The photovoltaic modules on these lamps are low-quality cast-offs. How else can your local discount store sell them for $10 for a set of 4?
- Ditto with the built-in rechargeable batteries: low-cost, low-quality. They don't hold a good charge for more than the first few weeks.
- The lights are incandescent (very inefficient) or fluorescent (four times better than incandescent, but still not nearly as efficient as LEDs), so they quickly drain the little power the small, cheap solar cells caputered and stored in the small, cheap batteries.
Good-quality solar LED landscape lights solve this problem of low, short-lived light on three counts: the quality of solar modules has been rising and costs have been falling; battery technology has improved substantially in the last three years; and LED lights use far less energy. On the other hand, it's fairly likely that if you buy solar LED landscape lights for $10 for a set of 4, you'll see them fail or fade just about as early as the older style models.
Solar powered floodlights and security lights typically come with a more robust, high quality, and larger solar panel than LED landscape lights. They should also have larger capacity batteries. Their greater light output means they need to capture and store more sunlight. If you're thinking of putting in a floodlight or security light and powering it with solar energy, make sure there's full sunlight where the solar panel will go, for at least a few hours each day. Some LED floodlights and security lights with a solar panel come with several feet of wire so that the solar panel can be mounted away from the light; look for this type of unit unless your light is going on a wall that faces the main path of the sun.
But remember that outdoor LED lights consume so little electricity, that a grid-connected LED light may make more sense. For example, a 50-foot long LED rope light with LEDs spaced one per inch (600 lights in all) can consume just 40 watts! You'll often pay quite a bit less for a grid-connected model than an equivalent solar model - no battery or solar panel required - and if you have an easily accessible source of power, you'll probably spend less on the electricity to power the lights, over the course of their lifetime, than you would on the solar modules and battery.
Take that 50-foot LED rope light that uses 40 watts. Assuming it's on for 3 hours a day, every day of the year, and that you pay $0.10 per kilowatt hour of electricity, you'll pay a grand total of about $44 for the electricity the rope light uses in a ten-year period. That's probably less than you'd spend on the battery and solar panel to power them, and you'll have more dependable light.
You might think it odd that an energy efficiency expert advocates not using solar-powered LED lights. But if you have a limited budget for energy efficiency upgrades, at this point I think it makes more sense to lower overall energy use through buying as much of the most efficient LED lighting you can buy (where it's really needed) than to convert less of your existing lighting to LEDs powered by solar power.
LED lights sold in North America typically come in two voltages: 120 volt AC, and 12 volt DC. You can buy LED rope lights, for instance, in both wattages, so you can build an outdoor LED rope light system using either grid connection or your own home-made solar electric system.
Types of LED lighting: Security, Safety/Utility, Setting
Security LED lights
Security LED lights with motion sensors can light up an outdoor area brightly when movement is detected at night. Because the LEDs use little electricity and are typically not on for very long (unless you have a particularly determined burglar on your porch, or a very hungry raccoon), you can get a lot of light even from a solar-powered LED security light with a small solar panel and small built-in battery unit.
Remember that illuminating a part of your house to ward off burglars is not necessarily effective. You are providing more light for the burglar to work with; and most people will not notice movement in a lit area as much as they might notice a flashlight moving around an unlit area. The main advantage of security LED lights is that you can find your way safely around without stumbling on or crashing into something. I find the motion-sensor floodlight on the back of my house is useful for night-time trips to the compost heap, but I don't think it would do a thing to deter a burglar!
The simplest option for a security LED light, if you already have an outdoor security light, is to switch the existing incandescent bulb to a compatible LED bulb. But before you do this, consider the cost savings. If you want the security light on all the time when it's dark out, it's definitely worthwhile to upgrade to an LED; the electricity savings mean the new bulb, even if it costs you $40, will pay for itself in less than a year (use my LED savings calculator to figure out exactly how soon it pays for itself in your situation).
On the other hand, if your outdoor security light is activated by motion, it is probably only going to be on a few minutes per night on average. Assuming 20 minutes per night, the payback period goes from under a year to 24 years! So don't replace existing motion-activated security lights with outdoor LED lights unless they get activated a lot - you can get much more energy-saving mileage for your money by doing other types of home energy upgrades.
I wouldn't recommend ripping out an existing incandescent-based security light to install a new solar-powered LED security light, unless the current fixture (as opposed to the bulb itself) isn't working properly, or you simply can't find an LED light bulb that is compatible with, and bright enough for, your fixture. If you can swap in an LED light bulb, you will wind up spending so little on electricity for it that a standalone solar powered LED security light may never pay for itself (especially considering that the battery and solar panel parts increase the likelihood that some part of the system will fail early).
And again, remember that the manufacture of the system has an energy cost as well as a financial cost - it takes energy to build solar cells and panels and batteries. You might save energy on your own electricity bill but counting the embodied energy in the system you may wind up using more overall.
Safety and utility lights
If you want to light up your outdoor spaces so you can eat outside, find your way to the garage at night, barbecue in the dark, or otherwise turn your yard into an extension of your indoor living place, there are a number of great outdoor LED light options for you.
LED flood lights - similar to an LED security light but without the motion sensor feature - can light up a large area while using next to no electricity. Remember that LED light bulbs can last up to 100,000 hours (although their power output does decline somewhat as they age). That's a lot of patio parties! You can get LED flood light fixtures that attach to a wall or ceiling, as well as ones that are driven into the ground with a stake so that you can light upwards at ornamental trees or other garden features.
LED rope lights are a good way to light up an outdoor area so that it is bright enough for a social setting. You can string LED rope lights up along fences, attach them to house walls, or line a pathway with them. They can easily be connected to the grid (just plug 'em in) and you can buy lengths anywhere from 8 feet to 150 foot reels.
Even a 150 foot reel, with LED lights spaced one per inch, for a total of 1800 lights, consumes as little as 120 watts of electricity. That can light up an entire large patio deck beautifully for less than you'd use on a 150-watt incandescent floodlight.
LED barbecue lights are simple solar- or battery-powered LED lamps you can use to see what's happening on the barbie when it's dark out. They clamp to an unheated area on the barbecue unit and you can direct their light down on the grill to check that those grill marks are perfectly aligned, or to test meat for doneness.
LED pond lights can be placed below the water line in in-ground pools or decorative ponds. While this is in some respects more for setting than for safety, keeping a bit of light in the water of your garden pond might help someone avoid falling in. Note that these lights cannot typically be placed more than 3 feet below the water surface in a swimming pool.
LED shed lights are typically solar-powered modules where you place a small solar panel on an outside wall or on the shed roof, facing the main path of the sun, and the light itself at the doorway to, or inside, the shed, so you can find what you're looking for. Note that if your problem is insufficient lighting during daylight - say your shed is surrounded by trees, as ours is - a less technological solution may be to replace part of the roof with translucent plastic roofing material. This makes sense especially if you're building a new shed or redoing the roof. But it is surely less work to just throw a self-contained LED shed light onto the shed than rip off an existing roof and rebuild it.
LED garage lights are higher capacity than LED shed lights. I discuss both LED and fluorescent garage lights on another page, Fluorescent garage lights. You can go from a simple replacement of an existing 24" or 48" fluorescent tube with an equivalent, but more efficient, LED tube, or you can install a solar unit.
LED lights to spice up the setting
The line between safety/utility and setting is a bit blurry, since being able to see the plate of food in front of you could be a safety issue, while the subdued lighting of a candle at your dinner table could be more for the mood. Since we're at the dinner table let's start with options for dining.
LED candles are a great choice for gentle lighting at the table, both indoors and out. These candles are made of translucent plastic that has the appearance of real wax; they have a small black wick on the top; and an LED light inside flickers inside, giving the appearance of a candle.
LED candles are battery powered and a single battery can last 200 hours or more. Best of all, they are self-contained; you don't have to attach them to anything or do any wiring or find a sunny location for solar panels.
I've seen people put these out at parties, and guests can't help themselves - everyone has to pick them up and have a look. They look like real wax candles and almost feel like wax too! And for outdoor parties they are great because they don't blow out when the wind picks up, they don't pose a fire risk, and they don't burn out after an hour or two.
Umbrella LEDs are another battery-powered option. These units consist of a donut-shaped module that splits into two halves; you clip the two halves together around the shaft of your patio umbrella, and the LEDs project light downward onto the table or space below.
You can either buy the LED donut as a separate unit, or you can buy an umbrella stand that comes with one of these lights. My own recommendation would be to choose the umbrella that best meets your needs, then buy an LED light to go with it - you'll have far more umbrella selection, and probably more LED light selection to boot.
Inset LED fixtures can be installed in deck/patio floor boards or balustrade posts, most easily when your deck is being built. They look great and if your deck is made of an unusual or particularly attractive wood (such as the sustainably harvested, eco-certified red cedar I built my front porch out of) they can really help accentuate the color or grain of the wood. You have to drill a hole through the wood to install the fixture - if you're even just a little handy with tools you should be able to manage it.
LED house numbers will let passers-by (and drivers-by) see your street address day and night. These large numbers are lit up by energy efficient LEDs (usually grid connected) and you can order just the numbers you need for your address.
LED landscape lights are the sensible replacement for those ever popular but always dim solar landscape lights sold over the past 10-15 years. They are coming down in price and as I mentioned above, because of the low power consumption of the light emitting diodes they use, and recent improvements in solar and battery technology, they tend to last longer and provide a brighter light. One of my neighbors has a very attractive system of LED landscape lights for her yard. It consists of one solar panel on a stake driven into her lawn, wiring laid down under the sod, and about a half dozen LED landscape lights that are tall metallic cylinders with a light near the top. They tend to stay lit all night long, whereas most of the older style solar landscape lights I see in my neighborhood are usually fading within an hour or so after sunset.
LED post cap lights are caps you can put on the top of 4x4 wooden posts along your patio edge. They are capped like a standard post cap and have a solar chip embedded in the top of the cap to charge the battery during the day. The light is emitted from a glazed section below the cap. These protect your posts from rain damage better than a wooden post cap and provide free lighting at night for years. You can get LED post cap lights in copper, white, or even Tiffany style finishes.
Outdoor LED lights are a great introduction to LEDs
We'll be seeing more and more LED technology over the coming years, as quality improves, costs come down, and electricity prices go up. I'm pleased by this development for two reasons: we need to cut our energy use as much as possible to stave off the worst impacts of climate change, so LEDs can help there; and for those of us who have already started the migration to lower-wattage lights by installing fluorescent lighting, we've had to suffer through the typically unattractive, glaring light of our fluorescent bulbs and tubes, and LEDs, unlike fluorescents, can truly provide a more natural, muted light.
So if you're interested in learning more about LEDs, or just trying a few out, outdoor LED lights might be a sensible place to start. You can see for yourself whether you like the quality and color of light they provide, and you'll get a sense for how little energy they use, without having to buy high-cost bulbs for indoor use. Remember that LED house lights provide a very directed light, and an LED bulb touted as an appropriate replacement for a given wattage incandescent bulb will often turn out to put off far less light, so they may not be suitable replacementsfor the indoor lights you use now. By trying out outdoor LED lights you'll get some experience with them and can decide how much upgrading you want to do indoors once indoor bulb prices start to drop, as they certainly will within the next few years.
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