Table of Contents

1. Watts vs. Watt-Hours: The Two Numbers That Actually Matter

2. Before You Do the Math: Factors That Affect Your Real-World Solar Output

3. What Can 100–200 Watts of Solar Power? Starting Small, Starting Smart

4. What Can 400 Watts of Solar Power? Portable Power for Everyday Use

5. What Can 800 Watts of Solar Power? Run Your Fridge, Cover Your Baseload

6. What Can 1,200 Watts of Solar Power? 

7. What Can 1,600 Watts of Solar Power? Power Your EV and Cut Your Bill by a Quarter

8. What Can 2,000 Watts of Solar Power? Your Start to Real Energy Independence

9. Above 2,000 Watts? Here's What to Consider

10. Common Appliance Wattage Reference Guide

11. Quick Reference: System Sizes at a Glance

12. How to Calculate How Many Watts of Solar You Actually Need

It's one of the first questions most people ask when they start looking at solar: how much can a solar panel actually power? 

The wattage on a solar panel's label tells you its theoretical energy output under ideal conditions. Your real-world output is most likely going to be a little lower than this max output. 

Whether that output is enough to run your refrigerator, charge your devices, or offset a real portion of your electricity bill depends on the stated panel wattage, and the exact output varies by location, season, weather, and the specific equipment you're using.

This guide cuts through the confusion. We'll explain what watts and watt-hours actually mean, and then walk through exactly what different system sizes, from 100W to 1,500W and beyond, can and can't do. 

If you're considering plug-in solar, balcony solar, portable solar panels, or a DIY solar setup, this is the foundation you need before you buy anything.

Watts vs. Watt-Hours: The Two Numbers That Actually Matter

These two terms get used interchangeably all the time. They mean different things, and the difference matters enormously when you're sizing a solar system.

Watts (W) — the rate of power

A watt measures how much power a device is using or generating at any given moment. Your refrigerator might run at 150W. A laptop might draw 40W. A 400W solar panel, in direct midday sun, produces 400W of power: right now, in that instant.

Think of it like the speedometer in a car. It tells you how fast you're going at this moment. It doesn't tell you how far you've traveled.

Watt-hours (Wh) and kilowatt-hours (kWh) — the total energy

A watt-hour (Wh) is one watt running for one hour. A kilowatt-hour (kWh) is 1,000 watt-hours, and it's the unit on your electricity bill. Your utility charges you per kWh consumed. When your bill says you used 900 kWh last month, that's 900,000 watt-hours of electricity over 30 days.

Back to the car analogy: watt-hours are the odometer. They tell you the total “distance” (i.e., the total energy) used or produced over time.

Putting them together: how solar output actually works

An 800W solar panel system running for 5 hours of good sunlight produces: 800W × 5 hours = 4,000 watt-hours, or 4 kWh of electricity. That's enough to run a full-size refrigerator (averaging ~150W) for about 27 hours, or charge a laptop (40W) roughly 100 times.

The number of productive hours your panels get each day is called peak sun hours, and it's one of the most important variables in any solar calculation. More on this shortly.

Quick reference: Watts = how much power right now. Watt-hours = how much total energy over time. To convert: watts × hours = watt-hours. Divide by 1,000 to get kilowatt-hours (kWh).

Before You Do the Math: Factors That Affect Your Real-World Solar Output

Solar panel wattage ratings are measured under controlled lab conditions: bright, direct light at a specific temperature, with the panel perfectly positioned. Real life is different. Before you calculate what a given system can power, here are the main factors that determine how much of that rated wattage you actually get to use.

Location and season matter for solar

Your panels only produce power when the sun is shining, and the intensity and duration of that sun varies dramatically by where you live and what time of year it is. Solar designers measure this as peak sun hours, or the number of hours per day when sunlight intensity reaches 1,000 watts per square meter, which is the standard used to rate solar panels.

According to data from the National Laboratory of the Rockies (NLR), the difference across the US is substantial:

 

A 1200W plug-in solar system in Phoenix gets roughly 6 peak sun hours on an average day, producing about 6.1–7.2 kWh depending on the efficiency. The same panel in Seattle in December gets closer to 1.5–2 peak sun hours, producing 1.5–2.4 kWh. Same hardware, very different output. 

Use the peak sun hours calculator to get location-specific estimates for your address before making any purchasing decisions.

Panel placement and angle affect output more than most people expect

The orientation and tilt of your panels are among the most consequential decisions you'll make, and the research on this is more nuanced than the standard advice suggests.

The south-facing rule: true, but latitude-dependent. In the Northern Hemisphere, south-facing panels at a tilt angle roughly equal to your latitude capture the most solar energy on an annual basis. 

This means your south-facing solar panels should be angled around 30° at mid-latitudes like Cyprus or the US Southeast, 45° for northern locations like Germany or the US Midwest and Northeast, and much shallower (10° or less) near the equator. For east/west systems, shallower tilts consistently outperformed steeper ones, a 10° tilt beats a 35° tilt, partly because steeper east/west panels cause self-shading and capture less sunlight.

East/west performs best in summer. East/west-oriented panels consistently outperform south-facing panels during summer months (May–August), and their morning/evening production profile better matches how most households actually use electricity. 

For balcony and facade installations where south-facing isn't an option, east/west is a solid orientation, especially at tropical latitudes. 

Keeping panels clean is critical. Research from both Spain and India confirmed that panels mounted vertically, as many balcony and facade installations are, gather less dust and debris compared to tilted panels. Since dust and dirt can reduce panel output by up to several percent annually, this is a practical benefit for plug-in and balcony solar setups. For ground mounted systems, we recommend cleaning off your solar panels every couple of months to help keep them as efficient as possible. 

A panel lying flat soaks up the least energy. A horizontal panel captures the sun’s energy well at the equinoxes but loses out significantly during the winter when the sun is low in the sky. Plus, it gets dirtier more quickly. For most US locations, a flat-mounted panel will underperform a tilted south-facing setup by 10–20% or more annually.

Watch out for shade. Even a small shadow across part of a panel can reduce output significantly, depending on the system design, because of how panels in series share electrical characteristics. That being said, research from tropical conditions found that shaded panels still produce 20–25% of their direct-sun output through diffuse irradiance and albedo, so shade isn't a complete shutoff, especially in locations with strong sunlight, like near the equator.

The practical takeaway. For plug and play solar setups, perfect placement isn't always possible. Your best bet is to aim for south or west-facing panels if you can, keep tilt shallow if you're mounting vertically, and avoid placing panels where they'll be shaded during peak sun hours. 

How temperature and solar panel equipment affect energy efficiency 

Temperature is another notable contributor to how well your panels work. Solar panels are rated at 25°C (77°F) under standard test conditions. However, in real-world use, panel surfaces can reach 50–70°C on warm sunny days, especially on south-facing walls or dark rooftops with limited airflow. Most panels lose roughly 0.35% of their output for every degree Celsius above that 25°C baseline. 

This means the peak-sun-hour advantage of a hot, sunny location like Phoenix is slightly offset by higher temperature losses compared to a cooler but cloudier location like Seattle.

Panel type and material, inverters, wiring, and battery charging and discharging can also cause small energy losses between your panel and your outlet. Depending on the equipment, location, and setup, you may lose up to 15% of your panel's rated output by the time it reaches a usable form. A 200W panel may deliver closer to 170W of usable power. 

A few things help minimize these losses: 

• Bifacial solar panels (i.e., panels that capture energy on both sides) and panels made from higher-quality materials like monocrystalline silicon tend to convert a higher share of available sunlight into usable electricity. 
• Vertically mounted panels, such as those used in balcony and facade installations, also benefit from better natural airflow than roof-mounted panels lying close to a hot surface, which helps keep operating temperatures lower. 
• Quality inverters and wiring reduce conversion and transmission losses downstream.

If you like to dive into the details, you can use this calculator to estimate your real solar output for your location. 

Storage matters: without a battery, you only have power when the sun shines

A plug-in or portable solar system without battery storage generates power in real time, during daylight hours. When the sun goes down, or goes behind a cloud for an extended period, production stops. If you're running devices directly from your panels or a microinverter, your power goes with it.

A battery or power station changes the equation. It stores the energy your panels generate during the day and lets you draw on it in the evening, overnight, or during cloudy stretches. If reliability and resilience matter to you, not just bill savings, battery storage is worth considering alongside your panels. 

We cover the interplay between solar panels and battery storage in our plug-in solar guide, including what to know about outage backup.

What Can 100–200 Watts of Solar Power? Starting Small, Starting Smart

The direct answer: a 100–200W system, after efficiency losses and accounting for 4–5 average peak sun hours, produces roughly 0.4–1.0 kWh of electricity per day. That's enough to keep your phone and laptop charged, run your WiFi router around the clock, power LED lighting, and run a small fan. It won't run a full-size refrigerator or offset a meaningful portion of your household electricity bill on its own.

What it will do is give you a tangible, immediate experience of generating your own clean energy, and a real reduction in the power you're drawing from the grid for your everyday devices. For renters, homeowners, campers, or anyone wanting to try out solar before investing in a full plug and play solar setup, this is a useful starting point.

What a 100–200W system can power

• Smartphones and tablets: 5–20W each. Your panels can keep multiple devices charged throughout the day with ease.
• Laptops: 20–50W. A single 100W panel in decent sun can run a laptop continuously during daylight hours.
• LED lighting: 8–15W per bulb. Four LED bulbs for 5 hours = ~300Wh. Very manageable for a small system.
• WiFi router: 5–20W. Always-on devices like routers are excellent candidates for solar offset — they draw consistently and predictably.
• Small fans: 40–100W. A box fan on medium speed runs comfortably from a 200W system with sun to spare.
• Portable power station charging: Many 200–500Wh portable stations can be topped up daily from a 100–200W panel, then used for device charging overnight.

What it can't reliably do

A 100–200W system will struggle with any appliance that has a compressor or heating element, such as mini fridges (50–100W running, but with high startup surges), coffee makers (900–1,200W), or window AC units (500–1,500W). These aren't impossible to run momentarily from battery storage, but they'd drain a small system's daily output quickly.

100–200W of solar is best for:

• Anyone who wants to start their solar journey without a large upfront investment. 
• Renters and homeowners who want to test out balcony solar or a window-mounted panel. 
• Campers, van lifers, and emergency preparedness setups. 
• Charging baseload devices while reducing everyday grid dependence.

A 100–200W portable solar panel system is one of the few solar options immediately accessible to renters today. These systems require no structural modification, are portable when you move, and are small enough to mount on a balcony railing, in a sunny window well, or on a patio.  

What Can 400 Watts of Solar Power? Portable Power for Everyday Use

The direct answer: A 400W portable solar setup, accounting for 4–5 average peak sun hours and typical efficiency losses, produces about 1.4–1.7 kWh of electricity per day. That's enough to run your everyday devices comfortably, keep a mini fridge running through the day, and charge a portable power station for evening use.

400W sits in a practical middle ground: more capable than a small 100–200W starter setup, but still genuinely portable. These are panel-plus-power-station systems you can move around your property, take camping, or reposition seasonally to follow the sun, rather than fixed plug-in systems designed to offset your home's grid draw.

What a 400W portable system can power

• Mini fridge: 50–100W running. A 400W system produces enough daily energy to run a mini fridge through daylight hours, with power station storage extending coverage into the evening.
• Laptops and devices: 20–50W each. Multiple devices charging simultaneously is well within reach at this system size.
• LED lighting: A 400W system handles whole-room LED lighting comfortably throughout the day and into the evening via stored power.
• TV and home entertainment: 30–100W. Several hours of TV daily barely touches this system's daily output.
• Box fans: 40–100W. Continuous fan use during daylight hours is easily covered.
• Power station cycling: A 400W panel can fully recharge a 500–1,000Wh portable power station in a day of good sun, giving you a meaningful energy reserve for overnight use.

What 400W can't reliably do

A 400W portable system won't run a full-size refrigerator long-term, and it won't make a measurable dent in your household electricity bill the way a fixed plug-in system can.

High-draw appliances like coffee makers (900–1,200W), window AC units (500–1,500W), or power tools are possible in short bursts from a large enough power station, but will deplete your stored energy quickly.

A 400W portable system will not charge an EV. A Level 1 EV charger draws around 1,400W, more than this system's total rated output, and far more than its realistic usable output after losses.

400W of portable solar is best for:

• Renters and homeowners who want meaningful portable power without a fixed installation.
• Anyone who wants off-grid power that's easy to set up.
• Campers, van lifers, and anyone who needs energy on the move.
• People who want a capable backup power setup for outages. 
  

What Can 800 Watts of Solar Power? Run Your Fridge, Cover Your Baseload

The direct answer: An 800W plug-in solar system produces roughly 3.2–4.0 kWh per day in average US conditions. That covers your household's core baseload devices: fridge, lights, router, TV, and phone charging running simultaneously during daylight hours. You won't eliminate your electricity bill at this scale, but you'll reduce it in a way that shows up in your monthly charges.

According to the US Energy Information Administration, the average American household uses about 29 kWh per day. An 800W system in good sun conditions covers roughly 10–14% of that.

What an 800W system can power

• Full-size refrigerator: A modern Energy Star fridge averages 100–150W. An 800W system offsets your fridge's daytime energy draw, with battery storage extending coverage into the evening.
• All core baseload devices simultaneously: Fridge, lights, TV, router, and phone charging all running at once from your panels during peak sun hours.
• Power tools (intermittently): Many power tools draw 500–1,200W. With a battery bank, short bursts of power tool use become solar-powered.
• Meaningful daily bill reduction: With 5 peak sun hours, an 800W system generates roughly 3.4 kWh/day, about 12% of your energy bill at national average rates.

Can an 800W system charge an EV?

No. A Level 1 EV charger draws around 1,400W, more than an 800W system's total rated output. Even with battery storage, an 800W system won't generate enough daily energy to contribute meaningfully to EV charging alongside your other household loads. You'd need a 1,600W+ system for that.

800W of plug-in solar is best for:

• First-time plug-in solar buyers who want a capable, manageable starting point.
• Homeowners and renters targeting a 10–14% reduction in their electricity bill.
• Anyone who wants to stay comfortably within the permit-free regulatory threshold where plug-in solar legislation has passed.

What Can 1,200 Watts of Solar Power? 

The direct answer: A 1,200W plug and play solar system produces roughly 4.8–6.0 kWh per day in average US conditions. At this size you're covering your full household baseload comfortably and generating enough surplus during peak sun hours to build a meaningful battery reserve for evening use.

A 1,200W system covers roughly 15–20% of the average US household's daily electricity consumption, and even more for smaller homes and apartments. It's also the largest system that falls within the permit-free threshold in states where plug-in solar legislation has passed, making it a practical choice for self-installed systems under current US regulations.

What a 1,200W system can power

• Full-size refrigerator, all day: At 1,200W, you have enough headroom to run your fridge throughout the day from solar and still build a battery reserve for overnight coverage.
• All baseload devices simultaneously: Fridge, lights, TV, router, and charging, all running at once, with capacity to spare.
• Window AC unit (partial offset): AC units draw 500–1,500W. A 1,200W system offsets meaningful AC runtime during peak sun hours, especially paired with battery storage.
• Power tools: Short bursts of high-draw power tool use are well within reach with a battery bank at this system size.
• Significant annual savings: With 5 peak sun hours, a 1,200W system generates roughly 5.1 kWh/day, worth $330+ per year at national average rates and even more in states like New York, California, and Hawaii.

Can a 1,200W system charge an EV?

Not reliably on its own. A Level 1 EV charger draws around 1,400W, slightly above a 1,200W system's total rated output. With battery storage and careful load management you could trickle charge an EV overnight from a full day's generation, but you'd be trading off coverage of other household loads to do it. If EV charging is a priority, a 1,600W+ system is the right starting point.

1,200W of plug-in solar is best for:

• Homeowners and renters who want to maximize their plug-in solar offset while staying within the clearest permit-free regulatory thresholds.
• Anyone in a lower-sun location who needs more output to hit their savings goals.
• People ready for a more capable system who want meaningful year-round production, not just peak-season output.

What Can 1,600 Watts of Solar Power? Power Your EV and Cut Your Bill by a Quarter

The direct answer: A 1,600W system produces roughly 6.4–8.0 kWh per day in average US conditions. At this output level, you're covering your full household baseload and generating meaningful surplus, enough to start making a real contribution to EV charging and to offset a significant portion of your monthly electricity bill.

A 1,600W system in good sun conditions covers roughly 25% of average US household daily consumption (around 7.2kWh), worth about $473+ per year at average US rates depending on your location and utility's electricity rate.

What a 1,600W system can power

• Full household baseload with surplus: Everything your 1,200W system covers, plus extra generation for higher-draw appliances and battery charging.
• EV trickle charging: A Level 1 EV charger draws about 1,400W. A 1,600W system is the entry point for meaningfully contributing to daily EV charging, especially when paired with battery storage for overnight charging, without sacrificing coverage of your other household loads.
• Window AC unit: With 1,600W of output and battery storage, running a window AC unit during peak sun hours becomes practical without depleting your daily energy budget.
• Washing machine cycles: A clothes washer draws 350–500W. At 1,600W, you can run daytime laundry cycles from solar without meaningfully denting your daily output.
  

What to know about regulations at this size

Most systems above 1,200W sit outside the current permit-free thresholds where plug-in solar legislation has passed and may involve utility notification, depending on your state.

Craftstrom's plug and play systems are an exception. They are designed specifically for the US grid and don't feed energy back into the grid, which addresses the core utility concern at this system size.

1,600W of plug-in solar is best for:

• Homeowners and renters who want a 25%+ reduction in their electricity bill.
• EV owners looking for solar to meaningfully offset their charging costs.
• Those who have a utility charging high energy rates or increasing energy costs.

What Can 2,000 Watts of Solar Power? Your Start to Real Energy Independence

The direct answer: A 2,000W system produces roughly 8.0–10.0 kWh per day in average US conditions, enough to cover the majority of a smaller home's electricity consumption, or a substantial share of a larger household's baseload. At this scale, energy independence becomes a real possibility, especially for apartment dwellers. 

A 2,000W system covers roughly 25–35%+ of average US household daily consumption, worth around $525–$660+ per year at average US rates. In high-rate states or households with above-average consumption, the savings impact is even bigger.

What a 2,000W system can power

• Near-complete offset for smaller homes: Smaller apartments and energy-efficient homes averaging 15–20 kWh/day can offset 40–71% of their consumption from a 2,000W system in good sun conditions.
• EV charging as a daily habit: At 2,000W, solar EV charging becomes a routine part of your energy profile. With battery storage, overnight Level 1 charging on solar-generated power is achievable.
• High-draw appliances without compromise: Dishwashers (1,200–2,400W during the heating cycle), window AC units, and washing machines can all run during daylight hours without meaningfully depleting your daily output.
• Extended battery backup: More panels mean faster battery recharging after an outage and more hours of backup power, making this the tier where solar-plus-storage starts to function as a genuine resilience system.
• Sustained overnight power: With sufficient battery capacity, a 2,000W system can generate enough during the day to potentially carry your home through the night without drawing from the grid.

2,000W of plug-in solar is best for:

• Homeowners who want energy independence.
• EV owners who want solar to cover their charging.
• Households in high-rate states.
• Anyone building toward a grid-independent future.

Above 2,000 Watts? Here's What to Consider

If your target wattage Is above 2,000W, plug-in solar alone may not be the most efficient path to your goal, but there are a few options worth understanding before ruling anything out.

Installing multiple plug-in solar systems

It's possible to run more than one plug-in solar system in the same home, and some households do combine systems to reach higher total output. However, this isn't as simple as plugging in two systems side by side.

You can have up to 2000W per electrical supply line, also known as a "phase." in your home. Most homes have two phases, meaning they can support two 2000W systems, or 4000W total. 

If you want to go beyond 4000W of plug-in solar, you need to hire an electrician to add a subpanel to your breaker box and get the subpanel inspected. This extra work gets you a ton of extra wattage; you can easily wire in thousands of additional watts to the subpanel, paving the way to full energy independence on your terms.    

Supplementing an existing system with plug-in solar

For households with an existing hardwired system, such as6kW+ of permitted rooftop solar, a combination approach may make the most sense: a smaller plug and play system for permit-free offset for seasonal energy spikes, and you still have your traditional rooftop system to do the heavier lifting. 

A dedicated hard-wired rooftop solar system

If your target wattage is 10kW+, your goal is to offset all of your home's electricity consumption, and your budget is $30K+, a professionally installed rooftop system, typically around 6–16 kW for most US homes, is worth considering. The upfront cost and installation process are significantly more involved than plug-in solar, but the benefits may be worth it, particularly in high-sun, high-rate states.

The right answer depends on your goals, your home, your budget, and your timeline. If you're not sure which direction fits your situation, our plug-in solar product pages include realistic output estimates and sizing guidance across all system tiers we carry.

Common Appliance Wattage Reference Guide

Before you can calculate how much solar you need, you need to know how much power your devices actually draw. Here's a reference table for common household appliances, based on typical running wattages from the US Department of Energy.

Note that these are running watts: the wattage required to keep an appliance operating. Many appliances (especially those with motors or compressors, like refrigerators and AC units) have a higher startup surge that lasts only a few seconds but can be two to three times the running wattage.

 

* All figures are approximate. Actual consumption varies by model, age, settings, and usage patterns. Check your appliance's label or use a Kill-A-Watt meter for precise measurements.

Quick Reference: System Sizes at a Glance

Here's a summary of what each system tier delivers, assuming an average of 4-5 peak sun hours per day. Your results will vary based on location and season. 

* Daily output estimates assume 4–5 peak sun hours. Results vary significantly by location and season. 

How to Calculate How Many Watts of Solar You Actually Need

Now that you understand the variables, here's how to put them together. This is the same framework solar designers use, adapted here for plug and play solar panel systems.

Step 1: Find your daily electricity consumption

Look at your most recent electricity bill and find your monthly kWh usage. Divide by 30 to get your average daily consumption. The average US household uses about 29.6 kWh/day, but yours may be higher or lower depending on home size, climate, and appliances.

If you only want to offset a portion of your usage, say, your 15% for your baseload devices (fridge, lights, router, TV) rather than your whole-home load, estimate just that portion. A targeted offset approach is often more practical and more cost-effective for plug-in solar systems.

Step 2: Find your average peak sun hours

Use NLR's PV Watts calculator with your address to get location-specific peak sun hours. The table in the caveats section above gives you a rough starting point for major US cities. 

Remember that winter values can be significantly lower than annual averages. This is worth planning for if year-round production matters to you.

Step 3: Apply the formula

Here's the core calculation:

Daily kWh needed ÷ peak sun hours per day = kW of panels required 

You may want to add an extra 15% to the kW needed to account for potential efficiency losses.

Example: You want to offset 3 kWh/day (your baseload devices). You live in Denver, which averages 5.5 peak sun hours.

• 3 kWh ÷ 5.5 hours = 0.55 kW (550W) of panels needed at 100% efficiency
• Add 15% for losses: 550W × 1.15 = 632.5W
• Round up to the nearest practical system size: an 800W system covers this comfortably

In Seattle in winter (2.0 peak sun hours), that same 3 kWh/day target would require: 3 ÷ 2.0 × 1.15 = 1,725W of panels. A meaningful difference, and a good example of why location matters so much when sizing solar.

Step 4: Match your number to a system size 

Once you have your target wattage from Step 3, matching it to an available system size is straightforward. 

If your number came in under 800W, an 800W system covers you comfortably. It's the entry point for meaningful home energy offset and handles most baseload devices in average US sun conditions.

If your number landed between 800W and 1,200W, a 1,200W system is the right fit. This is also the tier to consider if you're in a lower-sun location or want a buffer for winter months when output drops.

If your number came in above 1,200W, a 1,600W or 2,000W system is where you're headed. 

If your calculation put your target well above 2,000W, a combination of multiple plug-in solar systems and battery storage may work for you. If you have a larger budget ($30K+), a hard-wired, rooftop system may be worth considering.

You can browse plug-in solar systems across all size tiers here.