We all hear about solar energy all the time. Solar panels, solar generators, solar flashlights and lanterns, cellphone chargers, and more.
But if you’re not totally sure what solar energy is, how solar power works, and whether or not it could be a decent option for your home, RV, or hunting cabin, you need to know the nitty-gritty of what it’s all about.
That’s what we’re here for: providing you with solar energy information. So, if you’ve ever asked “what do solar panels do,” you’ve come to the right place.
Below, we address the basics of:
- Solar energy and what it is,
- Solar panels and how they work,
- How full solar panel systems work, and
- What it’s good for and where you can best use it.
Let’s begin with a brief history of solar power.
The History of Solar Power
Solar cells first came into being back in 1876 (yep, that far back!) when William Grylls Adams with his student Richard Day, discovered that selenium, when exposed to light, produces electricity. The selenium wasn’t efficient, but it did prove that light, without moving parts or heat, could be converted into electricity.
Of course, advancements took many years, and it wasn’t until 1953 when Calvin Fuller, Daryl Chapin, and Gerald Pearson discovered the silicon solar cell. This cell produced enough efficient energy to run a small electrical device.
A few years later, in 1956, the first solar cells became available commercially. The cost was significantly more than was practical for use, however, since 1-watt of solar cell was about $300. Solar cells started showing up in toys and radios that year, though.
In the late 50s and early 60s, the U.S. and Soviet Union both used solar-powered satellites in the space race, and solar power was the basic standard for powering space-bound satellites by the late 60s.
By the early 1970s, lower cost production for solar cells was discovered, which brought the price of solar cells way down from $100 per watt to about $20 per watt. Exxon spearheaded this research for use in off-shore oil rigs.
From the 1970s to the 1990s, a huge boom in solar-powered options came. Railroad crossings, microwave towers in Australia, telecommunication technologies, and remote homes without easier access to electricity started all using this renewable energy source.
And today, of course, solar power is much more affordable, easier to access, less expensive, and greener to produce than ever before.
A Quick Definition of Solar Energy
The literal definition of solar energy is: radiant energy emitted by the sun. This is another term for solar power.
A very basic overview of solar energy is that something called photovoltaic cells – combined together into what we know as solar panels – draw in energy from sunlight. This can be done either through direct sunlight – the most effective and efficient way – or through daylight, meaning even cloudy days produce solar energy.
The solar panels use this drawn solar energy as a source to convert into usable electricity. This electricity is then transmitted into your electronics and appliances to run them as traditional electrical energy would.
What is a Solar Panel, and How Does it Work?
A solar panel is a sheet of photovoltaic cells – as mentioned before – that are put into a metal frame.
These cells work together to collect solar energy.
Once the free, renewable energy is collected – i.e. sourced – from the sunlight, the internal wiring works in conjunction with the cells to convert the solar energy into usable energy that can run electronics and appliances.
What Are Solar Panels Made Of?
Solar panels are made of a frame – usually metal, such as aluminum – and the photovoltaic cells which are placed together in the frame. The cells are covered with glass and the panels have a backsheet on the rear for protection and insulation. These backsheets are typically made of a polymer material.
As to the solar cells themselves, the construction depends on the type of solar panel you’re looking at. There are two primary types you’ll find on the market.
Crystalline Solar Panels
Crystalline solar panels, either mono or poly, are made of crystalline silicon – c-Si – and are the more common of the two general types of panels. These are the panels that look like blue or black rectangular grids made up of smaller squares. The small squares are the actual cells linked together in a series, forming a circuit.
Crystalline panels are generally grouped in 60-cell or 72-cell panels.
These solar panels are generally covered in durable glass giving them a greater weather, heat, and water resistance.
Thin-Film Solar Panels
The other most common type of solar panel is a thin-film panel. These are typically used in large scale installations. These are also covered in glass, and use a couple different materials, depending on the exact type of panel.
Amorphous panels – best for low light conditions – are made of amorphous silicon – a-Si – but there are also cadmium telluride and copper indium gallium selenide cells. Unless you’re going utility-grade, you’re most likely to only deal with amorphous panels.
How Does Solar Energy Work?
In this step-by-step process, you’ll see how solar energy works.
- Solar panels absorb sunlight and daylight. This light is solar radiation, in three forms: ultraviolet light, infrared, and visible light. These different forms of light are absorbed at different levels, some more effectively than others.
- When the sunlight interacts with the silicon solar cells, the electrons begin to move.
- These moving electrons create the flow of electrical current, which is captured by nodes and wiring in the solar panel.
- The wires then feed this DC – direct current – electricity into a solar inverter.
- The solar inverter then converts the current into AC – alternating current – electricity that is useable by appliances and electronics.
Now, to make this energy useful for your home, the process looks a bit like this.
- Solar panels absorb the sunlight, as mentioned above.
- The panels convert the sunlight energy into DC electricity.
- The solar inverter does its thing by converting the DC electricity into usable AC electricity. This is the form of electricity used by most of your home appliances.
- If you’re using a solar generator or batteries, the electricity will then flow through your home – or RV or cabin, et cetera – powering your electronics and appliances.
- The excess electricity produced by your solar panels is fed back into the electric grid, or stored in your battery or generator.
How Do Solar Panels Generate Electricity?
For those of you who’re looking for the more technical, “deeper” answer on how solar panels generate, electricity, here’s the technical rundown.
Light consists of a variety of colors, both visible and invisible to the naked eye. If a prism or shard of glass catches light at just the right angle, you can see this in the rainbow of colors that splashes across the room.
The different colors come from different photons of light.
The photons carry differing degrees of energy, which is why there are color differences.
For example, blue light photons carry more energy than red. Ultraviolet light and infrared light are both forms of invisible light that either give us that warming tan – or burn if you’re my spouse – while infrared light just gives us “heat.”
Solar cells respond differently to the different light photons, just like we do.
These photons have characteristics of both waves and particles, and Quantum Mechanics goes pretty deep into it. We’re interested in the solar energy aspects, however, so we’ll stick to this: red light has a different wavelength than blue light.
The sun produces a wide range of colors – that glorious spectrum of sparkling color we get after rain comes to mind! – and each color has a different intensity. Solar panels read these different color intensities and converts them into different levels of energy.
Those differing lightwaves are absorbed by the photovoltaic cells – named this because of the meanings. Photo relates to light. Voltaic refers to electricity – think volts.
The photovoltaic cells then use the different components of the solar power system to convert this power into usable electricity that goes beyond the mere translation of light.
What Does a Solar Inverter Do?
Simply put, solar inverters are a type of electrical converter.
They convert the variable DC electricity into the utility frequency alternating current – i.e. AC current which your electronics can handle.
Solar inverters have special functions that are adapted for this photovoltaic use, which includes anti-islanding protection for safety and maximum power point tracking, which maximizes the power extraction from the system.
Solar inverters are mandatory for a functioning solar power system. Without them, you would have unusable energy collected from the sun.
Solar inverters are usually placed in an extremely accessible part of the solar power system, as close to the modules as possible. For residential use, the inverter is often mounted on the exterior side wall of the house that’s closest to the electrical main.
The inverter, electricity net meter, and electricity production meter all work together so that the power produced by your system is first consumed by electrical loads in current operation.
The balance of the power passes through the electrical grid – as noted above – and your electricity utility meter will actually turn backward if you produce more solar energy than you’re currently using in your house.
Note: Solar inverters are a little noisy. Do not place them near sensitive areas like children’s bedrooms.
Does it Matter Where Solar Panels are Placed?
It’s important to note that most solar power systems for home use are placed on roofs. The panels are laid out along roofs for a couple of reasons, though.
Placement on roofs frees up space in the yard. Placement on the roof is also likely to eliminate many issues of shade and shadow that placement on the ground or lower surfaces would create.
This placement on the roof should be positioned so that the solar panels get as much direct sunlight as possible between 9 a.m. and 3 p.m., the peak solar hours.
South-facing installation is also recommended to take advantage of the efficient light direction. If, however, there are trees blocking – or tall buildings, et cetera – then other positions may be more efficient.
It is possible to have moving brackets that direct the panels toward the sun as it moves through the sky during the day for maximum power absorption.
What is a Net Meter and How Does it Work?
When your solar power system is tied to the utility grid, like most residential urban sites will be, the DC power is “net metered.”
This means that it reduces the demand for power from the grid when your system is producing usable solar energy. This is what enables you to lower your utility bill via solar energy.
The net meter shows you the net consumption of power by the household. It doesn’t tell you how much energy you’ve pushed back into the grid, but it does indicate the difference between the solar energy and the standard energy taken from the grid. This is the “net usage” of your home. This is how your system is able to run your meter backward.
If the utility power goes offline, the grid-tied power automatically shuts off, which protects workers from power feeding back into the grid, during an outage, for example.
What is an Electricity Production Meter and How Does it Work?
An electricity production meter or electric meter, is the standard device we’re familiar with that’s attached to homes within the grid of an electricity supplier.
They show the electricity used by a household and enable the power company to bill the residence for energy use.
What Does a Solar Power System Require?
There are several components to the solar power setup for a home, RV, or other building.
Solar Panels
The average solar panel runs between 100 and 250 watts as a standard. Depending on what you’re powering, the number you need will vary greatly. You can somewhat easily determine your needs based on the following list that offers general usage requirements.
- Ceiling fan: 10-50W
- DVD Player: 15W
- CB Radio: 5W
- Modem: 7W
- Laptop: 25-100W
- Drill (1/4 inch) 250W
- Toaster Oven 1200W
- Blu-ray Player: 15W
- Tablet Recharge: 8W
- Satellite Dish: 30W
- Cable Box: 35W
- TV – LCD: 150W
- LED Light bulb (40-watt equivalent): 10W
- LCD Monitor: 100W
- Smart Phone Recharge: 6W
- Coffee Machine 1000W
- Fridge (16 cubic feet) 1200W
Solar Generator or Batteries
Depending on the size of the system you’re running, you’ll either need a generator that powers everything with the stored energy, or a few batteries. Batteries are more typically used for small setups like RVs, hunting cabins, and similar small use locations.
Solar Inverter
As mentioned above, you will need solar inverters to protect and run your solar power system properly.
Solar Wiring
Technically, there is no such thing as specified solar wiring, meaning there is no special wire made exclusively for the use with solar-powered systems. However, there are different wires that are rated for different uses.
When it comes to running solar power through your home or RV, you’ll need to verify the type of wire you’re using is appropriate for your situation. RVs, for example, should have THHN 10/2 tray cables since they’re rated to handle the temperature extremes that systems of that size will produce.
For charge control and battery bank, any type of DC stranded wire will do. 8-gauge is a popular option, but 6-gauge also works. 10-gauge, however, is the easiest to install in most circumstances.
Digital Monitoring Unit
To track your energy properly, a digital monitoring unit is handy. They allow you to track everything from voltage, charge levels, output, and cumulative amp hours on your entire system.
Mounting Hardware
Finally, for any system, you’ll need the right mounting hardware. Make sure all mounting brackets are high-quality with high ratings or you may lose your set up.
Residential Solar Energy Usage Cases
Solar energy can be used to power just about anything electrical.
However, there are limitations on solar energy for most consumers in present-day circumstances without the cost becoming prohibitive.
But the most solid examples of how the average person can most efficiently install and use solar energy include the following.
Small Electronics
Obviously, small electronics make sense for solar power. They don’t require a lot of electricity to charge and run them.
Laptops, phones, iPads, motion sensor lights, camping lanterns, radios, portable fans and more are all easily powered by solar energy.
And there are specific small panels and power banks designed for powering just these items. Some of the items have the solar panels built in – thinking solar lanterns and portable solar fans – while others run off small power banks or portable solar panels just as easily.
Tent Camping
If you’re hitting the campsite for more than a day or so, you may want to grab some portable solar panels to power your gear. They’re especially useful for primitive campsites or backwoods spots where standard electricity aren’t readily available.
Of course, you can use the power banks and small solar panels – some are designed to hang from a post on a tree, for example – to power everything.
Boating and Fishing
Boats and fishing trips are also fantastic situations for solar power.
Generally, sitting out on a river or maneuvering your way around a lake you don’t need significant power. However, there are solar-powered generators that are perfect for boating and allow you to run heftier electronics like air conditioners and coolers and fridges.
Sitting on the dock with a solar powered fan isn’t a bad way to go, either.
RVing
Of course, your home-away-from-home can easily be powered by the right solar powered set up.
The right battery, solar panels, inverter, and other gear can keep your motor home nearly fully solar-powered save for drive time.
Hunting Lodges
Off-the-grid hunting lodges are a great place for use of solar power. You don’t have to rely on location – apart from the placement of solar panels – to get power working in the place.
You can choose a few appliances to run while you’re there – generally I use the fridge and radio – or power the whole place.
This can be done through a full, permanent set up, or a portable set up, whichever suits your needs best.
Remote Houses
If you’re not so into cities and love a deep woods location, solar power can keep your home powered.
You’ll have to invest more than the average consumer since you’ll be relying fully on solar power and possibly wind power.
However, you don’t have to pay the extra fees or deal with the hassles of getting a county or state to install electricity for you from the grid.
Remote Cameras, Lights, Et Cetera
Finally, if you’ve got a secondary location, an outbuilding that’s not visible from the house, or something similar, solar power is a great way to go for powering your equipment.
Your vacation home can keep up appearances of visitors and your business can be seen from a remote location if you have the right solar-powered camera or lights installed.
Solar Energy and the Environment
Of course, one of the biggest questions anyone has about solar energy is the impact of solar energy on the environment.
As far as the actual use of solar energy, it is a green, renewable energy alternative to fossil fuel powered energy. It uses no resources and does not damage the environment in any way.
On the manufacturing and disposal side of the equipment required for solar energy, however, there are some negative impacts on the environment.
Admittedly, everything else that isn’t 100% natural has similar impacts, however, so it’s hard to compare the impact neutrally.
Producing solar panels requires resources like copper, cadmium, and nickel. Silicon and lithium are also required.
These demands outstrip supplies today and for the future.
However, the finite resource of these minerals isn’t the only issue. The mining activities to produce the minerals impacts the environment negatively through the extraction methods and chemical separation processes.
Toxic waste from this process often is not responsibly taken care of. Soil erosion and mercury contamination also cause issues, while mining itself pollutes the water, air, and soil. These practices all harm local biodiversity and populations.
The positive in this, however, is that well-made solar panels and products will last 25+ years, which is significantly longer than most fossil fuel based products that breakdown more quickly.
This does reduce the waste and disposal rates at least, though not the manufacturing impact as more people desire solar energy use at home.
The Benefits of Solar Energy
As stated above, the actual use of solar energy is a renewable, green energy source that doesn’t burn fossil fuels or use other depleting resources. But there are other advantages and benefits to using solar energy in your home or workplace.
Solar Power Saves You Money in the Long Run
Initially, setting up your solar power system can cost a pretty penny. Prices are going down on equipment and installation costs, however.
But in the long run, as you use solar energy, you’ll reduce your electricity bill significantly, if you’re efficiently using your equipment. No more gas and electricity bills for the stove and fridge or A/C!
Solar Power is Safe for Indoor Use
Solar power is safer than gas-powered energy. This means using a solar generator, for example, reduces your risk of fires when using this sort of generator for your home, lodge, boat, or backup power.
Solar Energy is Much Quieter
If you’re looking for a quiet power source that saves you money, then solar energy is also your go-to.
The generators and batteries aren’t like noisy gas-powered options. This makes solar power great for home, camping, RV, or any other setting where sensitive ears may be listening.
Solar Power is Portable
If you have the right equipment – such as portable solar panels or power banks – you can literally take electricity with you anywhere.
If you’re hiking overnight, there are solar-powered equipment pieces that compact down into tiny, lightweight objects you can easily tuck into your pack.
You can bring along a portable solar panel with your RV, or you can even reorganize your landscaping easily with the portable solar-powered lanterns and pathway lights.
Or, if you go back and forth between a couple of residences – think summer home/winter home, beach house/city house – you can take the whole rig with you. No need for the additional investment on extra panels, generators, et cetera.
Solar Power is Safe for Outdoor Use
Whether you’re looking to keep your fountain pumping water, heat your pool, keep your tent lit until bedtime, or just about any other outdoor activity, solar-powered equipment is generally designed for safe use outdoors. After all, the panels must be in the sunlight to draw in the necessary power.
The equipment is usually designed to be able to withstand intense winds, heavy snowfall, and heaps of rain. Just verify the IP rating of your equipment before purchasing to guarantee you’ll be able to use it properly in your given environment.
Solar Equipment Costs Little to Maintain
While you do have to account for some minimal maintenance fees over time, generally speaking, you’re looking at installation costs and piecemeal replacements.
Solar panels are often built to last something like 25 years, while the other necessary equipment is planned for nearly or equally as long.
Verify warranties before purchasing to make sure you’re getting something that will work for you, though.
Solar-Powered Equipment is Reasonably Easy to Install
In most cases, solar-powered equipment is fairly easy to install. The one aspect that you’re likely to need a contractor for is rigging the electricity into your home or RV system safely.
Specific pieces, however, like pool heaters and security cameras, are easy enough that just about anyone – even the non-handy folks in the room – can install themselves.
Drawbacks of Solar Energy
Mentioned above, solar energy equipment production does have a negative impact on the environment. There are a few other drawbacks of using solar energy, as well.
Solar Panel Manufacturing Isn’t Green
As mentioned above, the actual manufacturing processes rely on chemicals and mineral extraction, meaning the actual products themselves are rarely eco-friendly.
While it reduces your ecological footprint once in use, it’s important to remember that the environmental impact before your purchase is fairly negative.
The Up-Front Cost Can Be Prohibitive
For some, the initial price tag on setting up a full solar-powered system for the home can be overwhelming and undoable. Equipment ranges in prices from $100 for a 100-watt solar panel to several hundred dollars for a basic “kit” that includes panels, battery, and inverters.
You need to carefully calculate the cost and possibly save up in advance to be able to switch over to solar energy for your home.
There are options to lease and finance solar panels, which helps reduce the burden, but also increases the timeframe before you’ve saved any money.
Solar Energy is Somewhat Weather Dependent
Of course, solar power means you need solar exposure. If you live in certain regions of the world, you have much lower solar access than other places.
There are different approaches you can take to this issue, such as using multiple amorphous solar panels in low-light areas, but the problem remains the same in long winters or consistently bad weather for any season.
This is not to say that panels cannot collect sun during rainy and cloudy days. They do absorb the various forms of light during these times. However, the power will be limited, since the resource is limited.
Many Solar Products Use Large Amounts of Space
If you’re putting your solar panels on the roof, you’re probably okay with the space being taken up.
However, if you’re heating your pool and don’t want to hire someone to install the panels for you, you’ll find that solar panels use a ton of space.
For pool heaters, for example, you’ll discover that 1-square foot of solar collector is needed per 1-square foot of pool. If you’ve got a giant yard, that’s not too big of an issue. If, however, you live in an urban setting, you’ll find the size may be prohibitive for your use.
The Storing of Solar Energy Can Be Expensive
Solar energy can either be used immediately – such as charging your cellphone from a power bank while hiking the Appalachian Trail – or it needs to be stored in batteries for later use.
Some devices have small, built-in batteries for their use at night – think solar-powered security lights – but others do not, and you’ll have to get some hefty batteries or a generator to store up the power.
The more energy you store up, of course, the more storage you need. The more storage you need, the more expensive your set up costs will be.
This is Solar Energy in Brief
What is solar energy? It is power drawn from the sun by a collection of photovoltaic cells.
How do solar panels work? They convert energy from the sun into usable electricity that can be used to power electronics and appliances like laptops and refrigerators.
How do solar panels work on a house? You install solar panels, along with a generator or series of batteries, inverters, and solar wiring to create a power system that gives energy to your home. This reduces your use of grid power and even turns back your meter to save you even more money each month.
Is solar energy good for the environment? As far as use goes, yes. As far as production goes, there is an environmental impact. This impact is being reduced each year as new technology emerges, however.
What are the benefits of solar power? The use of solar power saves you money in the long run, uses green renewable energy, it’s safe for indoor and outdoor use, it’s quiet, and it’s easy to install in most cases.