Our sun constantly unleashes an immense amount of energy, but only a fragment of that energy actually strikes Earth. That small sliver of energy — equal to a continuous stream of 174,000 terrawatts of electricity at any given moment — is enough to satisfy the planet’s entire energy use more than 10,000 times.1
We’ve only begun to develop technology that converts this constant stream of solar power into clean energy in recent years. However, the reality is that we’ve harnessed our sun’s energy for thousands of years. From drying food and hanging clothes on the line, to solar-powered backpacks, grills and garbage bins, we’ve found unique (and sometimes quirky) ways to tap into the sun’s tremendous energy reserves.
So, What is Solar Energy?
We experience solar energy as sunlight and feel it in the form of heat. Scientifically speaking, this invisible force — officially called solar radiation — is actually comprised of tiny packets of energy called photons. These photons may be considered tiny, but they are the fundamental source of all climate and weather systems on Earth.2
Before you start to feel overwhelmed by all the hard science of solar power, rest assured that we’re going to answer a few important questions:
- How is solar energy generated?
- How do people use solar energy?
- What are the benefits of this powerful resource?
- How can you take advantage of this green energy?
So, let’s dive in.
How Does Solar Energy Work?
If you’ve ever taken a science class, you know that our sun — just like every other star in the universe — is a giant nuclear ball of gas. Comprised of mostly hydrogen and helium, the sun is an enormous nuclear fusion reactor, and nuclear fusion is how the sun generates energy.
Deep within the sun’s core, where the pressure and temperature are unbelievably high, hydrogen undergoes a series of reactions to eventually become an entirely different element — helium — through nuclear fusion. Eventually, helium atoms fuse to become even heavier elements. This union of atoms — where lighter elements become heavier ones — releases massive amounts of energy into space in the form of light and heat. That energy from the sun then radiates outward in the form of electromagnetic radiation, where it eventually reaches the Earth’s surface at the speed of light.
Confused yet? Let us explain. You’ve probably heard of UV rays. This is a type of electromagnetic radiation emitted from the sun. Most humans see only a very small spectrum of radiation — or visible light waves — that strikes the Earth from our sun. Other types of waves such as microwaves and infrared rays are also invisible to us.
These electromagnetic waves essentially deliver the sun’s energy to us! We can harness the sun’s energy from these waves to generate clean, renewable energy used to power homes and businesses. No emissions and no pollution.
How is Solar Energy Used?
Over time, humans have discovered many ways to harness the sun’s energy. Obviously, solar panels immediately come to mind, as photovoltaic solar panels are an efficient way to use the sun to generate electricity. Many people have utility scale solar plants in mind with large solar panel fields. However, there are many more technologies that can capture energy from the sun for a variety of uses.
Let’s start by discussing our bread and butter — photovoltaic solar panels (PV) — and then dig into the lesser-known-but-just-as-interesting ways to utilize the sun.
Solar Energy Systems to Produce Electricity
There are two main solar energy technologies to convert sunlight into electricity:
- Solar photovoltaic systems (solar panels) and
- Concentrating solar power plants (also called CSP plants).
Solar Photovoltaic Systems
Also called PV cells or solar cells, solar PV systems serve as the electricity powerhouse of the solar panel. Each cell consists of two thin silicon sheets, and these sheets act like a battery: One is positively charged, and the other is negatively charged. When you join the two layers and expose them to sunlight, they produce an electrical current! A solar panel contains many of these battery-like cells to maximize electricity generation.
But since solar panels can absorb only certain types of electromagnetic radiation, most of the sunlight that strikes a PV cell isn’t converted into electricity. In fact, most of the sun’s energy isn’t viable; UV rays produce only heat energy, and infrared rays are too weak to generate electricity.3
While we know how to extract the maximum energy possible from fossil fuels, we are still learning how to maximize our use of solar. However, there’s no competition when you consider the environmental impact of solar. Since it generates no emissions or pollution, solar wins hands down. In fact, the EPA designates electricity produced from solar power as an energy source with the highest environmental benefit.4
Concentrating Solar Power Plants
CSP plants rely solely on thermal energy from the sun to generate electricity. While there are three types of CSP plants — parabolic trough, compact linear fresnel reflector, and the power tower — all use relatively the same approach to produce electricity.
Using highly reflective mirrors to concentrate sunlight on a single point, CSP plants heat water that drives the traditional steam turbines used in coal plants. The difference? CSP plants don’t generate greenhouse gas emissions.
CSP plants can also generate electricity after the sun sets because the water gets so hot it continues to produce steam for several hours. With the use of thermal storage, CSP plants can help relieve stress on the energy grid when electricity demand is high.5
The main challenge with both CSP plants and solar photovoltaic systems is that solar heating is fairly difficult to accomplish. Solar energy isn’t spread evenly, and it’s diffused across the entire Earth — literally. In the United States alone, solar irradiance — the rate at which sunlight falls onto a surface — is pretty varied, as most of the solar power falls in Southern California, Arizona, New Mexico and West Texas.6
Solar to Produce Thermal Energy
There are a couple of other ways to capture thermal energy from solar, including solar space heating and cooling and solar hot water heating collectors. The difference between these methods and CSP plants is that space heating and water heating doesn’t generate electricity. Rather, these systems manipulate solar’s heating characteristics to regulate building temperatures, which can save on water heating costs. You might call it ‘solar thermal power.’
Solar Space Heating & Cooling
Perhaps the simplest method of using solar power, you can implement it in your home today! Just by strategically opening and closing your curtains and windows to heat and cool your home, you have created a passive solar home. You’re using the heat of the sun to regulate your home’s climate without the use of electricity.
You can create an active solar home, but that requires additional equipment. To truly save on heating costs, you’d need rooftop solar collectors, black boxes that absorb sunlight and trap heat, to distribute heat throughout the house.
Solar Water Heating Collectors
Water heating accounts for nearly 20% of your energy bill.7 A solar water heater is an environmentally-friendly solution to help you reduce your bill each month.
Solar water heaters work like solar space heaters. After the solar collector is installed, the hot water heater uses a heat transfer fluid to transmute heat from the collector to the water tank. Once heated, you can use the hot water in your home!
Top Benefits of Solar Energy
Originally, the increase in demand for renewable energy was due to the perceived scarcity of fossil fuels.8 Now, renewable energy sources such as wind, solar and biomass are rapidly growing — not because of oil — but as a response to climate change and other environmental concerns. Today, people (and companies) are adopting solar power in droves because they care about keeping the planet clean. The top benefits of solar energy include:
- Saving $259 billion in global climate change damages with a reduced carbon footprint9
- Preventing $167 billion in health and environmental damages by decreasing pollution 9
- Reducing or completely eliminating their electricity bills with rooftop solar
- Easing the stress on the energy grid during peak usage
How You Can Take Advantage of Solar Energy
There are two main ways you can take advantage of the sun at home:
- Rooftop solar panels and
- A green electricity plan that powers your home with 100% solar energy.
Business owners can use options like rooftop panels, power purchase agreements, carbon credits, and more!
At Chariot Energy, we offer solar power to our customers with or without solar panels. Our green electricity plans help you get 100% solar energy in your home without installing solar panels. For people with panels, we’ll buy the excess energy produced by your rooftop solar power system, at a dollar-for-dollar, watt-for-watt energy rate for a year.
Ready to go full solar and reap the benefits today?