Are you looking to go solar?
Active solar energy and passive solar energy are both types of power from the sun. But, there are some major differences between them. If you’re new to solar, you may not know what these are.
Don’t worry, we’re here to help! Read on for the difference between active solar energy and passive solar energy.
What’s Solar Energy?
Solar energy is energy harvested from the sun’s rays that’s turned into electricity. This electricity then helps power our homes, business, and more.
Think of the sun as one large generator. The energy it sends comes in the form of photons. Solar panels capture these photons and convert them into usable power.
Why Go Solar?
It’s one of the cleanest energy sources and it’s easy to access wherever you are. It’s sustainable, reusable, and doesn’t impact the environment.
The sun actually gives more energy than the whole planet will use in a year in only one hour. If we can all harvest that energy, there can be a complete shift away from fossil fuels and unclean energy. Which means less pollution for the planet.
Vast breakthroughs in solar technology have propelled it into a viable energy source. But it’s not utilized enough yet, considering the technology that’s now available.
In fact, in the US it only accounts for 1.6% of total electricity generation. But, it is growing in popularity, and fast too. In the first quarter of 2020, solar made up over 40% of all new energy production capacity in the US.
This means the popular it becomes, the easier and cheaper it will be to access. There are already tax breaks and incentives for installing solar panels. It’s set to be a power revolution, so if you want to be part of it there’s no better time to. Buy solar today!
Active Solar Energy
Active solar energy is the form most people think about when they talk about solar power. Active solar energy setups need external energy sources. In other words, this means a backup system like heat pumps and radiators.
This is to power the capture, storing, and conversion of solar energy as it goes into electricity form. It can then cool, heat, and power your home or neighborhood, depending on the design and set up.
The setups we’re talking about are your typical solar panels. You can use flat-plate PV panels. You can mount them on roofs vertical and horizontal. You can also have them stationary. But make sure they have access to a lot of sunlight.
How Does Active Solar Energy Work?
It works by using liquid or air to capture the heat of the sun’s rays. This then pushes through into a storage container until your system can convert it.
Liquid is what most systems use as it’s better for conducting heat and energy. But air comes with the bonus that it won’t freeze, making it more suitable for cooler temperatures.
Both can heat and cool your home or business. You will see collectors that use liquid referred to as hydronic collectors. Air ones are air collectors. Here are some examples of active solar energy systems.
Active Solar Space Heating
This heating system uses the collectors referred to above to collect thermal energy. It’s then sent through the house/building via pumps or electric fans.
Solar Water Heaters
These water heaters produce thermal energy to heat water. They can heat homes, commercial spaces, and even swimming pools. Again, a collector is in place, along with a tank to heat the water.
Depending on your collector, the max temperature will vary. But, most can heat water to over 200 degrees Fahrenheit. Enough for commercial use.
Photovoltaic (PV) Cells
Also known as solar cells are small panels with semiconducting material on the face. This material is what turns sunlight into energy.
Usually, it’s silicon-based and it produces a direct current when hit with sunlight. As they use sunlight, they’re useful anywhere from Alaska to New Mexico. They can also work either connected or not connected to the electric grid.
If linked to the grid, they let you supplement the energy you use from your utility company during the day. This usually covers you for peak demand hours.
Independent cells power anything from lights to remote settlements away from main power supplies. The main thing to remember is it’s limited to daylight hours, and won’t generate in the dark.
Passive Solar Energy
Passive solar energy design is where you use the sun’s energy to heat and cool a home through exposure. It’s all about how sunlight strikes a building. And it relies on you designing your home in specific, clever ways.
Depending on the building materials they can:
- reflect
- transfer
- absorb
Your home or building will have a design that ensures all the above, with the best results. Heat from the sun causes air movements. Designers can use them to predict results in certain spaces and designs.
These basic, predictable responses to solar heat inform design elements. From material choices, placement, and direction of your home. The goal is effective, efficient, natural heating, and cooling of your home/building.
Unlike active solar energy, passive systems are simple and more design features. There are no major electrical or mechanical devices involved. No pumps, fans, or controls needed to move this solar energy.
Heating
The goal of passive systems is to absorb and capture heat from the sun inside building elements. It’s released when there is no sunlight, keeping the temperature stable.
The main elements of passive design for heating are thermal mass and south-facing glass. It’s used to absorb, store, and distribute heat. Depending on the style of home you want, there are different approaches used to implement them.
Cooling
For cooling, it works by:
- lowering unwanted heat gain through the day
- exchanging warm inside air for cooler outside air
- allowing non-mechanical ventilation
- storing cool air from night to help moderate daytime temperature
The simplest solutions include shade-providing trees, cross-ventilation, and shades on the south-facing glass.
Active Solar Energy and Passive Solar Energy, Know the Difference
So, there you have it! Now you know the difference between active solar energy and passive.
The main difference is one needs devices and power to harness energy from the sun. The other uses integrated non-mechanical building elements. It’s best to go for active solar energy if your building/home already exists. If you’re building your home from scratch, then consider integrating passive solar design.
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