A few weeks ago, I received an email from a friend asking for my advice on solar panels. He had just received the largest power bill ever, and after that thought that there must be some advantages in owning some solar panels.
Having seen an advert for different sized panels he wanted to know what the benefits were of having different sizes.
Despite the simple appearance, they are not like plug-and-play devices for your computer…
Though seemingly simple, nothing more than a panel with two cables and a charge controller their use is complicated.
The output of these panels varies by the demands of how much electricity we need, and compounded even further by the fact that these panels do not produce steady wattage in all conditions. I say this all to tell you – the power output is almost always going to vary.
Despite this, whether you live in a traditional residential house or homestead, solar energy systems are can be incredibly valuable. It all depends on what you want to achieve from using them.
Someone living in a traditional house may want to be able to charge or run some appliances to reduce power bills, while a homesteader may want to completely power a home off-grid. And then there are people who want to buy a full solar panel kit for their RVs.
Before I go deeper into this article, I advise you to think carefully about what you want to do with your solar system. Ultimately, a 200W panel will produce double the power of a 100W and a 300W panel will produce triple the power.
Long story short, a 100W solar panel can run several light bulbs, a printer, a ceiling fan, or a blender, it can charge a phone or even a laptop, and can power a Wi-Fi router, or many small devices.
Table of Contents
Solar Panel Electricity Production
Let’s start with a location that allows solar panels to be exposed to 6 hours of direct sunlight. This kind of panel has the capability of producing 600W from a 100W panel in ideal conditions. More on that in a bit.
Now, it cannot supply all of this power all at once: I don’t get 100 watts on demand from my panel. Instead, the best way to use 100-watt solar panels is to direct the energy they create into a battery.
In this way, a battery could supply smaller, low-drain devices (like a few lamps or LED lights) over a long period of time or one or two higher-drain devices for a shorter period of time. The amount of power that is delivered over time is called watt-hours, abbreviated “Wh.”
A 200W panel has the capability of producing 1200W, and a 300W panel has the capability of producing 1800W.
100w x 6 hours=600W
200w x 6 hours=1200W
300w x 6 hours=1800W
This is the net amount of power generated over time this is power we have available to run our devices. If I want that power I’ll need to store it in a battery. Both lead-acid batteries and lithium-ion batteries are decent options for use in conjunction with a solar array.
How Many Watts Do I Need?
The watts required to allow a device to work is calculated in most cases by using a simple formula:
Volts X Amps = Watts
An example of this is an item that requires 240 volts and 0.5 amps will require 120 watts.
You need to understand the power consumption of individual pieces of equipment if you want to be able to determine what can be run and for how long.
My laptop uses 30W so it is possible to run this for 10 hours and nothing else. Alternatively, I can run the laptop for 6 hours, my router also for 6 hours, charge my cell phone for 2 hours, and only use 450W leaving power left over for something else.
This is why calculating your demand in Wh is so important. Remember that you are drawing power over time while any of your devices are in use!
To take things one step further, we should look at the power requirement of individual items of electronic equipment. That way, we can understand what combinations we can run and for how long on a 100W solar panel.
What You Can on a 100-watt Solar Panel
…under reasonable weather conditions:
|✅ LED Light bulb||✅ CFL Light bulb|
|✅ Incandescent Light Bulb||✅ LCD/LED Display or TV Screen|
|✅ Game Console||✅ Laptop, Notebook, or Netbook|
|✅ Wi-Fi Router||✅ Printer|
|✅ DVR player||✅ Cell Phone Charger|
|✅ Cordless phone||✅ Alarm Clock Radio|
|✅ Ceiling Fan||✅ Blender|
|✅ Charging Power tools|
What You Cannot Run On a 100w Solar Panel
|❌ Vacuum Cleaner||❌ Clothes Iron|
|❌ Hair Dryer||❌ Toaster|
|❌ Microwave||❌ Electric Furnace|
|❌ Space Heater||❌ Water Heater|
|❌ Central Air Conditioner||❌ Clothes Washer|
|❌ Clothes Dryer||❌ Stove Top|
|❌ Electric Oven||❌ Dishwasher|
|❌ Freezer||❌ Desktop Computer|
|❌ CRT Monitor||❌ Satellite Receiver|
|❌ Blender||❌ Coffee Maker|
|❌ Electric Kettle|
What You Can Run On a 200w Solar Panel
…under reasonable weather conditions.
Remember, earlier we established that a 200W panel will provide us with 1200W of electricity or double that of a 100W panel.
|✅ Blender||✅ Coffee Machine|
|✅ Electric Kettle||✅ Microwave|
|✅ Wi-Fi Router||✅ Printer|
|✅ Laptop, Notebook, or Netbook||✅ DVR player|
|✅ Cell Phone Charger||✅ Cordless Phone|
|✅ Alarm Clock Radio||✅ Coffee Maker|
|✅ Ceiling Fan||✅ Satellite Receiver|
|✅ Toaster||✅ Clothes Washer|
|✅ Ceiling Fan||✅ Power Tools|
What You Cannot Run On a 200w Solar Panel
|❌ Vacuum Cleaner||❌ Hair Dryer|
|❌ Electric furnace||❌ Game Console|
|❌ Clothes Iron||❌ Space Heater|
|❌ Water Heater||❌ Central Air Conditioner|
|❌ Clothes Dryer||❌ Stove Top|
|❌ Electric Oven||❌ Dishwasher|
|❌ Freezer||❌ Desktop Computer|
|❌ CRT Monitor|
What You Can Run On a 300w Solar Panel
…under reasonable weather conditions.
Equipment that will run on a 300W Solar Panel under reasonable Weather Conditions
Remember, earlier we established that a 300W panel will provide us with 1800W of electricity or treble that of a 100W panel.
|✅ Game Console||✅ Laptop, Notebook or Netbook|
|✅ Wi-Fi Router||✅ Printer|
|✅ DVR player||✅ Cell Phone Charger|
|✅ Cordless Phone||✅ Alarm Clock Radio|
|✅ Coffee Maker||✅ Ceiling Fan|
|✅ Satellite Dish||✅ Vacuum Cleaner|
|✅ Clothes Iron||✅ Hair Dryer|
|✅ Toaster||✅ Microwave|
|✅ Space Heater||✅ Clothes Washer|
|✅ Stove Top||✅ Desktop Computer|
|✅ CRT Monitor||✅ Satellite Receiver|
|✅ Blender||✅ Electric Kettle|
|✅ Power Tools|
What You Cannot Run On a 300w Solar Panel
|❌ Electric furnace||❌ Water Heater|
|❌ Central Air Conditioner||❌ Clothes Dryer|
|❌ Electric Oven||❌ Dishwasher|
Common Devices In Detail
LED Light Bulbs
LED or light-emitting diode light bulbs have become the standard for those searching for an efficient lighting option.
A typical cheap LED light bulb producing light levels equivalent to a traditional 60-watt bulb will provide 800 Lumens. This is with a life of 10,000 hours while only consuming 10 watts.
Verdict: With 60 watts available, it would be possible to run six of these bulbs for 24 hours per day on a 100W panel, 12 on a 200W panel, and 18 on a 300W panel.
CFL Light Bulb
A CFL light bulb or a compact fluorescent light is a technology that was made to replace incandescent light bulbs.
CFLs will use between a third and a fifth of the electrical power that an incandescent bulb will use. To compare with an LED a CFL bulb producing 800 Lumens will use 13 to 15 watts.
Verdict: Using 15 watts it would be possible to run four of these bulbs for 24 hours per day on a 100W panel and 8 on a 200W panel and 12 on a 300W panel.
Incandescent Light Bulb
An incandescent light bulb is an electric light with a wire filament within a gas-filled glass bulb that produces light when direct current passes through it.
This old technology is cheap to produce, but is very inefficient, and has a very short life. This type of bulb will only convert 5% of the energy into light.
Verdict: With one bulb requiring 60 watts, it would only be possible to run one of these bulbs for 24 hours on a 100W panel 2 on a 200W, and 3 on a 300W.
LCD/LED Display or TV Screen
The power consumption of a computer or TV display varies significantly.
The technology, quality of construction, and size of the screen have a significant effect as does if the display is showing static or moving images. The brightness and power-saving settings of the screen will also have a significant effect.
Verdict: On average, a 22-inch LED-backlit LCD will use approximately 30 Watts and would be able to run for as many hours as required on any of the panels.
Game Console / DVD Player
Game consoles have become a standard entertainment device to play games, go online, watch movies, or stream videos. But how much energy do they use?
Estimates show that an average video game console will use around 90 watts when it is being actively used for gaming and 1-2 watts during standby mode when the console is off but still plugged in.
When used for other functions such as streaming videos, consoles will use power ranging from 50-70-watt range.
Verdict: It’s hard to determine a solar panel’s efficiency with power restrictions on a 100W, but it should have no problem with a 200 or 300W panel.
Laptop, Notebook, or Netbook
Laptops, notebooks, and netbooks are designed to run on a battery and to be more power-efficient, therefore they will generally use less power than average desktop computers.
This type of product normally uses integrated graphics. These are far less power-hungry than PC video cards. The screen size, and whether the device is being used whilst charging have a large effect on power consumption.
Estimates show that power consumption can be between 20 and 100 watts when running from its internal battery.
While in charge mode, the laptop battery power consumption will increase by 10 to 20 percent. Estimates show that 60 watts are the average power consumption for 14-15-inch laptops when plugged in.
Verdict: At a 60W power consumption, a laptop can be charged for 10 hours on a 100W, 20 hours on a 200W, and 30 hours on a 300W.
Wireless routers, an essential device for anyone who requires internet or network access are usually low-power consumers since they are solid-state devices with no moving parts, they are usually left on 24 hours a day by those that require constant uninterrupted internet access, although this is not necessary.
Estimates show that a Wi-Fi router uses between 2 and 20 watts, with 6 watts being an average figure.
Verdict: With this low power level, we can run this device 24 hours a day on any of the panels. This is a best-case scenario, really, when it comes to a solar panel’s efficiency.
An average home-use inkjet will typically use 30 to 50 watts when it is printing. It is important to remember that any device left in standby mode will still use power even though it’s not currently doing anything. Most printers left in standby will draw around 3 to 5 watts of power.
Verdict: In most cases, if a printer will only be used for a short time, the power supply from a 100W will be able to cope with this, but there might be some time restrictions. The power from a 200 and 300W should be more than adequate.
DVR Player / Cable Box
Digital Video Recorders, TV, and HD set-top boxes have made great advances in energy reduction in recent years. A good estimate would be 11-26 watts of power for a typical HD-DVR, and 8-15 watts.
Verdict: Most styles of DVR players would function fine from all the panel size options.
Cell Phone Charger
Cell phones, tablets, and smartphones over the years have become far more energy-efficient because they are designed to run on a battery for longer periods.
Cell phones use approximately 2 to 6 watts when charging, while a charger left plugged in without a phone will consume 0.1 to 0.5 watts.
Verdict: Charging any number of cell phones, tablets, and similar devices is no problem with the power that we have available from all the panels.
A cordless phone will typically be left plugged in 24 hours a day. It will use between 2 and 3 watts of power per hour when being used, and when it needs a recharge.
There is very little that can be done to reduce the energy consumption of a cordless phone. That’s because it is almost always either in use or in standby mode.
Verdict: 2 to 3 Watts is no problem from all the panels.
Alarm Clock Radio
Alarm clock radios are another example of a common household item whose energy consumption has been greatly reduced by the advanced development of electronics over the past few years.
Older devices may well use up to 5 watts, but a modern one will only use around 2 watts.
Verdict: Again 2 watts is no problem for the power from all the panels.
When making coffee the average simple-style coffee machine will use around 300 to 600 watts to make 2 cups of coffee and 1000 to 1500 watts for 8-10 cups of coffee.
A good estimate would be that a coffee maker will use 800 watts in 10 minutes, and in doing soproduce 4 cups of coffee.
Verdict: Well, the good news is you can make coffee, on a 100W – but not too many cups – while a 200 and 300W will offer no restrictions.
Ceiling fans help cool a room by circulating air which creates a cooling effect. There are a variety of sizes and range from 36 inches (0.91 m) to 56 inches (1.42 m) using 55 to 100 watts, a typical 48-inch ceiling fan will use 75 watts.
Verdict: A ceiling fan will operate on a 100W panel, but not for very long. It should have no problems on a 200 or 300W panel.
There are many types of vacuum cleaners. They range from small portable machines to large industrial models. On average, household vacuum cleaners will use between 500 and 3000 watts of energy. An average model will use around 1400 watts.
Verdict: It’s probably best to buy a good strong broom if you only have a 100 or 200W panel – but you can put the broom away if you have a 300W panel.
Irons work by electricity heating an iron plate. In most modern designs, it will also heat water that can be sprayed on fabric to remove wrinkles.
The power consumption of an iron will change as temperature settings are altered, and they can range between 800 and 2000 watts. That’s with an average of 1100 watts on a high setting.
Verdict: Many modern fabrics do not require ironing, and line drying in the wind does remove many wrinkles. However, with a 300W panel, an iron can be used when necessary.
The energy use of a hairdryer depends on the settings or functions that are required, unheated air can use as low as 70 watts of power. However as heat settings are increased the power consumption will also increase to an average of 1500 watts.
Verdict: A 300W panel is the minimum size required to operate a hairdryer.
A toaster only needs a few minutes to complete its job. However, it does require between 800 and 1500 watts of energy to be able to complete its function. An average toaster will require around 1200 watts.
Verdict: Smaller models will work on a 100W but anything larger will require a 200 or 300W panel.
Larger microwaves will use more power as they operate more quickly and with more power.
A compact microwave will use between 500 and 800 watts during a heating cycle, while a larger microwave could use 850 to 1800 watts depending on the function that has been selected. An average modern microwave will use around 1200 watts.
Verdict: A small basic microwave oven will work on a 100W panel, but larger more powerful models will require a 200 or possibly a 300W panel.
An electric furnace is a type of heating system that utilizes electricity to heat air that is forced through ducts in a home and then heats the home.
Modern furnaces, depending on their size and how much heating is required will require a power input of between 10 kilowatts to 50 kilowatts.
Verdict: An electric furnace will not function from the power supplied by any of the solar panels.
Space heaters are electric devices that are portable and can be moved to any location in a home that requires heating. These heaters function by heating the air and circulating the air around the room, most common convection space heaters will require 1500 watts of energy for them to function.
Verdict: 1500 Watts is beyond the capability range of a 100W and 200W solar panel, however, it will work with a 300W panel.
An electric water heater heats water for your daily needs within your home.
Electric water heaters would normally be running for 3 hours a day to provide enough hot water, although newer more efficient models may run for only half the time. An average water heater will use around 4000 watts.
Verdict: Again, this is far too much demand for all solar panels – something you’ll want to think about when going about your future solar installation.
Central Air Conditioner
The amount of energy that an air conditioner will use depends on the climate of the region and the type of unit installed.
A central air conditioner will normally be used for between 3 and 7 months of the year depending on the climatic conditions. Although smaller units may use less an average central Ac will use approximately 4000 watts of power.
Verdict: An air conditioner will not run from any of the solar panels.
A clothes washer or a washing machine is a common home appliance used in many homes. Most of the energy that a clothes washer uses is to heat the water rather than operating the various cycles.
Around 80-90% of the energy consumption is used to heat water, alternatively, a machine can be connected to a different hot water source although power is still required to heat the water in the alternative source.
A clothes washer will use 400 to 1300 watts, depending on the wash cycles that are being used. With care, this power demand could average about 500 watts.
Verdict: A 100W solar panel could run a clothes washer on a low power cycle, a 200W would allow further functions whilst it should work well with a 300W panel.
Clothes dryers demand high energy since they need to spin and produce heat at the same time. The energy requirement of a dryer will vary between 1800 watts and 5000 watts, a typical dryer will use around 3000 watts.
Verdict: If you use a clothes washer, you will have to hang your clothes on a washing line as a dryer will not operate on any of the solar panels. This is regardless of the solar panel’s efficiency or size.
The energy requirement of an electric stove top varies. Smaller elements will use in the region of 1000 watts, while a larger element could use more than 3000 watts.
A stovetop will gradually increase its power use as the temperature increases until the required temperature is achieved. As an estimate, an element will use around 1500 watts per hour of heating on a setting of medium to high.
Verdict: At 1500w, an electric stove top is an appliance to forget about, as it will not run on a 100W solar panel or a 200W but should be fine on a 300W panel.
Ovens’ energy requirements depend on the temperature it’s set to. Most of the cooking requires a temperature between 300 and 425 Fahrenheit (ca. 218 °C) degrees.
An average oven will use 1000 to 5000 watts, although a more modern oven may use around 2400 watts on medium to high heat.
Verdict: With all solar panels, you will go hungry unless you have another way of cooking food.
I guess if you are not going to be able to cook the food you will not need a dishwasher, but just in case a modern dishwasher is energy efficient and will not use a lot of water.
Dishwashers will use between 1200 and 2400 watts of power, with an average dishwasher consuming around 1800 watts.
Verdict: You will not be using one of these to wash your dishes.
Due to recent technological advances, a newer model freezer will use approximately 100% less energy than an older style model.
A new model of a freezer will use between 30 and 100 watts of power depending on size, indoor temperature & efficiency. A typical modern 15 Cu. Ft. freezer will use about 1 to 4 kW per day.
Verdict: Well, I suppose if you are not going to be able to cook, you don’t need to freeze food anyway!
An average desktop computer uses between 60 and 300 watts. It is very difficult to quantify exactly the quantity of power that computers use since there are many hardware configurations.
The computer power supply specification cannot be used to measure energy use because the power supply output is advertised as the max amount that it is capable of supplying.
The high-end video cards used for gaming especially 3D rendering will use much more power than normal usage.
Verdict: Estimates show that an average modern desktop PC will require approximately 100 watts of power, and that does not include the display screen. A 300W panel is essential for this you won’t see a 100-watt solar panel run a desktop computer.
CRT was constructed using an old form of technology. They utilize a vacuum tube with an electron emitter. Since a 17-inch CRT display monitor would use approximately 75 watts, it would require too much power for us to be able to operate it.
Verdict: Due to the level of performance and power consumption issues of this technology production has ceased, and they are no longer manufactured.
Depending on the technology and design a satellite receiver could require in the region of 450 watts.
Verdict: This will not operate from a 100W solar panel with the other equipment required, however, it should be possible with a 200 or 300W panel.
A blender is a small kitchen device that will only be used for a short duration, however, since it must have the power cut into relatively hard produce it requires a high level of power in the region of 500 watts.
Verdict: Since the power is only required for a short duration this device will work well with all panels.
An electric kettle is a device like a coffee machine, in that it heats water. Depending on how much water is in the kettle, it would use around 800 to 1000 watts, even though it only takes a few minutes to complete its function.
Verdict: This is a fast-running item so the 800 to 1000 watts is available on a 200 and 300W panel but not a 100W panel.
There are many different types of power tools, drills, circular saws of various sizes, etc. Whatever the task there is a power tool available to complete the task. Will a 100 watt solar panel produce enough power for your tools?
Unfortunately, no. Most range between 750 and 1200 watts.
Verdict: Some will work on a 200W panel however a 300W is best. However, it should be possible to charge the batteries of battery-powered tools from a 100W panel.
The answers as to what will run on power generated by solar panels are often vague since the amount of power that is generated varies according to several factors. Let us see why solar panels produce power at varying levels.
Despite their very simple appearance solar panels are very complex. At the simplest level, the sun’s rays strike the panel and knock electrons off the atoms that make up the panel. The flow of electrons through the panel is an electric current.
The construction and design of these panels allow them to change sunlight into electricity, using an inverter to get the power where it needs to go and into DC electricity.
The power produced by a panel is not constant, i.e. It’s not just on or off. The panel needs to be in the correct position to achieve maximum power production.
If the panel faces the correct direction and at the correct angle, then the sun will contact the surface at certain times of the day. The more direct the sun, the more power or electricity the panel will produce.
If the cloud blocks the sun it will reduce the amount of power that is being produced
This is a perfect day for solar panels to produce plenty of electricity. Not a cloud in the sky. Consequently, the potential power production chart may be altered.
If we want to power a refrigerator during the day, and it requires more than 1 unit of power, it will not work throughout the whole day.
That said, the solar panel’s efficiency depends on what kind of panel you’re using and what kind of connector, along with a myriad of other factors.
Anything that interferes and prevents the sun from contacting the panel will also affect the output. Shade from a tree or a building has a significant effect on the panel’s efficiency, as will sand, dirt, snow, or even bird mess.
Unfortunately, although the design is very simple, today’s solar panels are not very efficient. A solar panel may well state that it will produce 100 w, however, it will rarely do so.
A good quality 100w solar panel may produce 95w, a 200w panel may produce 190w, and a 300w panel may produce 290w.
The flow of electricity is far more efficient when the device is cool, however, the panel requires direct sunlight, and will as a matter of course heat up. The heat reduces the efficiency and consequently, the quantity of electricity produced is also reduced.
We have shown that many items both individual and combinations can be run from different-sized solar panels. Panels of 100, 200, and 300W individually are suitable for items that require low amounts of energy for them to function.
Recharging batteries and low-power items such as modems and cordless phones work perfectly well from these panels, however many domestic appliances such as washing machines require far too much power.
There is an inherent inefficiency in this technology.The power that can be produced is subject to several external influences that make the power that is available slightly unreliable.
For many, the use of solar is far too complicated to consider using, since the variation in the power that they generate varies and is quite complicated to work out.
Many test the ground and experiment by starting small. A good project is to provide solar power for a workshed. This is relatively cheap and easy to accomplish and nothing of importance is going to be damaged.
Despite all the problems associated with the use of solar panels for supplying power to a house, it’s not impossible.
I meet all of my electricity needs with solar panels, and I must say that it is rewarding financially. It also very emotionally satisfying. It’s worth the effort without a doubt.
Three years ago, I bought an off-grid Cortijo in a small valley in the Andalucian mountains. Although, perhaps the lifestyle is in my genes as my grandfather and his four brothers were Homesteaders in Alberta Canada in the 1900s.
The mountains of Spain are a difficult place to grow many of the flowers that I was used to in the UK. However, veggies grow well year-round. Peppers, tomatoes, potatoes, lettuce, cucumber, melons, and chard all fare well in the Mediterranean climate. Almond trees provide me with a cash crop of around 1 ton while still retaining some to make almond milk and flour.
Meet the rest of the Homesteading Hippy team here.