Do Outdoor String Lights Use a Lot of Electricity Find Out Here

Outdoor string lights are surprisingly energy-efficient, especially when using LED bulbs, which consume up to 80% less electricity than incandescent ones. Running a typical 100-foot LED string uses less than 20 watts per hour, making them a cost-effective and eco-friendly choice for ambiance. Enjoy your outdoor space without worrying about sky-high energy bills.

Key Takeaways

• LED string lights use up to 80% less electricity than incandescent bulbs.
• Check wattage ratings to estimate energy use and avoid overloading circuits.
• Use timers or smart plugs to reduce runtime and lower energy costs.
• Solar-powered options eliminate grid electricity use for eco-friendly lighting.
• Dimmer switches help adjust brightness and save power when full light isn’t needed.

Do Outdoor String Lights Use a Lot of Electricity? Let’s Break It Down

You’ve probably been there: you’ve just strung up those beautiful outdoor string lights, and your backyard instantly feels like a cozy, magical retreat. But as the sun sets and the lights flicker on, a nagging thought creeps in—*how much electricity are these using?* Will your next power bill look like a small mortgage payment? If you’re like most homeowners, you want ambiance without breaking the bank.

Outdoor string lights are a staple for patios, decks, gardens, and holiday displays. They’re affordable, easy to install, and instantly transform any space. But with rising energy costs and growing environmental awareness, it’s smart to ask: do outdoor string lights use a lot of electricity? The short answer? It depends. But the good news is, with the right choices, you can enjoy your twinkling oasis without worrying about sky-high bills. In this guide, we’ll explore how much power different types of string lights consume, what factors affect energy use, and how to enjoy beautiful lighting without the guilt or the sticker shock.

How Much Electricity Do Outdoor String Lights Actually Use?

Understanding Watts, Volts, and Kilowatt-Hours

Let’s start with the basics. Electricity use is measured in watts, and your utility bill tracks usage in kilowatt-hours (kWh). Think of it like miles per gallon in a car: watts tell you how much energy a light uses at any moment, while kWh tells you the total energy consumed over time.

For example, a 10-watt bulb running for 100 hours uses 1,000 watt-hours, or 1 kWh. At the average U.S. electricity rate of $0.15 per kWh, that’s just 15 cents. Now imagine 20 bulbs on a string—each using 10 watts. That’s 200 watts total. Run them for 4 hours a night, and you’re using 800 watt-hours (0.8 kWh) per night. Over 30 days, that’s 24 kWh—about $3.60. Not terrible, but it adds up if you’re using multiple strands or running them longer.

Incandescent vs. LED: The Big Difference

Here’s where things get interesting. Traditional incandescent outdoor string lights use far more electricity than modern LEDs.

• Incandescent bulbs: Typically 5–15 watts per bulb. A 25-bulb string could use 125–375 watts total.
• LED bulbs: Usually 0.1–0.5 watts per bulb. The same 25-bulb string uses just 2.5–12.5 watts.

That’s a massive difference. In fact, LEDs use up to 90% less energy than incandescents. I once replaced a 300-watt incandescent string with a 10-watt LED version and couldn’t tell the difference in brightness—only in my wallet.

For example, running a 300-watt incandescent string for 5 hours a night, 30 days a month, costs about $6.75. The same setup with LEDs? Less than 25 cents. That’s a $6.50 monthly savings—over $78 a year. Multiply that by several strands, and you’re looking at real money.

Real-World Example: A Typical Backyard Setup

Let’s say you have three 25-foot LED string lights, each with 20 bulbs at 0.3 watts. Total power draw: 18 watts. Run them for 4 hours a night:

• Daily use: 18 watts × 4 hours = 72 watt-hours (0.072 kWh)
• Monthly use: 0.072 kWh × 30 = 2.16 kWh
• Monthly cost: 2.16 kWh × $0.15 = $0.32

Even if you have five strands? That’s still under $2 a month. Compare that to incandescents: five 200-watt strands would cost over $18 monthly. The math is clear—LEDs are the way to go if you care about energy use.

What Affects How Much Electricity String Lights Use?

Bulb Type and Wattage

As we’ve seen, the type of bulb makes the biggest difference. But within LED and incandescent categories, wattage varies.

• LEDs: Mini LEDs (0.1–0.2 watts) are great for subtle ambiance. Larger “globe” or “candle” LEDs (0.3–0.5 watts) are brighter and better for entertaining.
• Incandescents: Edison-style bulbs (5–10 watts) are nostalgic but power-hungry. Stay away unless you’re okay with high bills.

Pro tip: Check the packaging. Reputable brands list total wattage or watts per bulb. If it’s missing, assume it’s incandescent—or just not worth the risk.

Number of Bulbs and String Length

More bulbs = more power. A 50-foot string with 50 bulbs uses twice as much energy as a 25-foot string with 25 bulbs—even if both are LEDs.

I learned this the hard way when I tried to drape lights across my entire backyard. I bought a 100-foot commercial-grade LED string (100 bulbs, 0.4 watts each = 40 watts). It looked stunning, but I realized I didn’t need that much coverage. I cut it in half, used two shorter strings, and saved 20 watts—plus made the layout more manageable.

Ask yourself: Do I need to light the whole yard, or just a seating area? Sometimes less is more—and more efficient.

Usage Time and Frequency

How long you run your lights matters more than you think. Running lights for 2 hours instead of 6 cuts energy use by two-thirds.

Here’s a relatable story: My neighbor, Sarah, loves her patio lights. But she used to leave them on all night. Her husband installed a simple timer, and now they turn off at 10 PM. She says the ambiance is just as good, and her energy use dropped by 40%. Win-win.

Consider:

• Using a timer to automatically turn lights off after a few hours.
• Only turning them on when you’re actually using the space.
• Using motion sensors (for security lighting) instead of leaving them on all night.

Voltage and Transformer Use (Low-Voltage Systems)

Some outdoor lights use low-voltage systems (12V or 24V), powered by a transformer that converts standard 120V household current. These are common for landscape lighting.

Low-voltage lights use less power overall, but the transformer itself draws some standby power. However, it’s usually minimal—often less than 1 watt when idle.

For example, a 20-watt low-voltage LED path light string uses about 20 watts, while the transformer might use 0.5 watts when off. Still, it’s more efficient than a 100-watt incandescent string.

Tip: Look for Energy Star-rated transformers or smart transformers that shut off completely when lights are off.

Comparing Outdoor String Lights: A Data Breakdown

Let’s get into the numbers. Below is a comparison of common outdoor string light types, their energy use, and estimated monthly costs (based on 4 hours/night, $0.15/kWh).

Light Type	Bulbs per String	Wattage per Bulb	Total Watts	Monthly kWh	Monthly Cost
Incandescent (mini)	25	5	125	15	$2.25
Incandescent (Edison)	20	10	200	24	$3.60
LED (mini)	25	0.2	5	0.6	$0.09
LED (globe)	20	0.4	8	0.96	$0.14
LED (solar-powered)	20	0.3 (charged by sun)	6 (when on)	0.72 (battery-powered)	$0 (after initial charge)
Low-voltage LED	30	0.3	9	1.08	$0.16

Note: Solar lights don’t draw from the grid, but their batteries need recharging via sunlight. In cloudy areas, they may need supplemental charging.

This table shows a clear pattern: LEDs dominate in efficiency. Even the most power-hungry LED string (globe) costs under 15 cents a month. Incandescents, on the other hand, cost 20–40 times more.

Also notice solar-powered lights. They have zero ongoing electricity cost, but performance depends on sunlight. I’ve had solar strings that barely last 2 hours on winter nights. But in summer, they’re fantastic—and free to run.

Smart Ways to Reduce Energy Use (Without Losing the Glow)

Switch to LEDs—It’s a No-Brainer

If you’re still using incandescents, stop. LEDs are cheaper to run, last 10–20 times longer, and produce less heat (safer for outdoor use).

When shopping, look for:

• “Energy Star” or “Energy Efficient” labels.
• Wattage listed clearly (e.g., “0.3W per bulb”).
• IP44 or higher weather resistance rating (for outdoor use).

I replaced all my old strings with LEDs last year. The upfront cost was $120, but I’ve saved over $60 on electricity so far. They’ll pay for themselves in two years—then keep saving.

Use Timers and Smart Controls

Timers are the unsung heroes of energy savings. A $15 plug-in timer can cut usage by 50% or more.

Better yet: smart plugs or smart string lights (Wi-Fi or Bluetooth). With an app, you can:

• Turn lights on/off remotely.
• Schedule them to match sunset/sunrise.
• Use motion detection (great for security).
• Monitor energy use in real time.

I use a smart plug for my patio lights. I set it to turn on at dusk and off at 10 PM. No more forgetting to switch them off. And I can turn them on from my phone if I’m running late.

Go Solar (If You Get Enough Sunlight)

Solar-powered string lights are perfect for areas with 4+ hours of direct sunlight. They charge during the day and glow at night—no wiring, no electricity cost.

But they’re not for everyone:

• Pros: Free to run, easy to install, eco-friendly.
• Cons: Less reliable in winter, shorter run time, may need backup charging.

I use solar lights in my garden—they get full sun all day. They last 4–5 hours, which is perfect for evening dinners. For my covered patio (shaded), I stick with grid-powered LEDs.

Use Reflective Surfaces to Maximize Light

Here’s a pro tip: brightness isn’t just about wattage. A well-placed light can feel brighter if it reflects off light-colored walls, fences, or patio furniture.

For example, I hung my string lights lower (about 7 feet) and angled them toward my white pergola. The reflection makes the space feel twice as bright—without adding more lights or wattage.

Other tricks:

• Use mirrors or metallic planters to bounce light.
• Install lights under eaves or overhangs to create a “glow” effect.
• Use fewer, higher-quality lights instead of many dim ones.

Are Outdoor String Lights Worth the Energy Cost?

Balancing Ambiance and Efficiency

Let’s be honest: outdoor string lights aren’t just about lighting—they’re about feeling. They create warmth, intimacy, and joy. A few dollars a month is a small price for that.

But if you’re using incandescents or running them 12 hours a night, the cost adds up. With LEDs, timers, and smart choices, you can enjoy the glow without guilt.

I’ve hosted countless dinners under my string lights. Guests always say, “Your backyard feels like a resort!” And I get to tell them: “Thanks—and it costs less than a coffee a month to run.”

Environmental Impact: Small but Meaningful

Every kilowatt-hour saved reduces your carbon footprint. The average U.S. household emits about 7.5 tons of CO₂ annually from electricity. By switching to LEDs, you could save 100+ kWh per year—about 100 pounds of CO₂.

Multiply that by millions of homes, and it’s a big deal. Plus, LEDs last 15,000–25,000 hours (vs. 1,000 for incandescents), so you’re also reducing waste.

When to Splurge—and When to Save

Not all string lights are created equal. Cheap LEDs may flicker, fade, or die quickly. Invest in quality:

• Look for UL or ETL certification (safety standard).
• Choose copper wire (more durable than aluminum).
• Opt for dimmable or color-changing options for versatility.

But you don’t need to buy the most expensive ones. Mid-range brands (like Brightech, GE, or Philips) offer great value. I’ve had a $35 LED string for 5 years—still going strong.

Final Thoughts: Yes, You Can Have It All

So, do outdoor string lights use a lot of electricity? Only if you let them. With modern LED technology, smart controls, and a few simple habits, you can create a stunning outdoor space for pennies a day.

The key is making informed choices: switch to LEDs, use timers, and right-size your setup. Don’t be afraid to experiment—try solar for sunny spots, low-voltage for pathways, and smart controls for convenience.

At the end of the day, outdoor lighting is about joy. It’s about sharing meals under the stars, watching kids play in a softly lit garden, or just unwinding with a book on a warm evening. With a little planning, you can enjoy all of that—without worrying about your electricity bill.

So go ahead. String up those lights. Turn them on. And let the magic happen—guilt-free.

Frequently Asked Questions

Do outdoor string lights use a lot of electricity?

Outdoor string lights typically consume minimal electricity, especially LED versions, which use up to 80% less energy than incandescent bulbs. The exact usage depends on bulb type, length, and daily usage hours.

How much electricity do LED outdoor string lights use?

LED outdoor string lights use very little electricity—usually 5–20 watts for a 20-foot strand, depending on bulb count and brightness. They’re an energy-efficient choice for long-term outdoor lighting.

Are incandescent outdoor string lights less efficient?

Yes, incandescent outdoor string lights use significantly more electricity, often 40–100 watts for a similar length, making them less cost-effective and less eco-friendly than LEDs.

Do solar-powered outdoor string lights save on electricity?

Solar-powered outdoor string lights use no grid electricity at all, drawing energy from sunlight. They’re ideal for reducing energy bills and are perfect for off-grid or eco-conscious setups.

How can I reduce electricity usage with outdoor string lights?

Opt for LED or solar-powered lights, use timers or smart plugs to limit runtime, and choose lower-lumen bulbs to minimize energy consumption without sacrificing ambiance.

Do outdoor string lights impact my monthly electricity bill?

Outdoor string lights have a negligible impact on your bill if you use LEDs and limit usage to a few hours nightly. For example, running a 10-watt LED strand for 5 hours costs less than $0.50 per month.