Active vs Passive Solar Heating: Key Differences 
Active vs Passive Solar Heating: Know the Difference!
Active and passive solar heating is nothing but two simple strategies to capture the energy of the sun. This captured energy is then used for room heating, water heating & even for the generation of electricity.
In this post, I am here with an in-depth guide on these two methods (i.e. active & passive solar heating) to capture solar energy and transform them into heat energy.
We will learn how active & passive solar heating methods work, their advantages, disadvantages & a clear comparison of active vs passive solar heating.
Let’s start by knowing what passive solar heating is?
Passive Solar Heating
Passive solar energy makes use of the sunlight to generate heat in the interior of the house.
For example, when you get into a car on a sunny day, sun rays enter the car through the windows and are absorbed by the car’s seats and floor and this heat gets trapped inside the car and keep the interior warm for a very long time.
Another example of passive solar heating can be seen in greenhouses. Passive solar heating is what makes greenhouses grow plants all-round the year. Sun rays enter the greenhouse through the rooftop glass windows and get absorbed by the items inside the greenhouse.
These items then emit heat to provide a warm environment to help the plants grow.
So, you must be thinking, how passive solar heating can help you? The answer is simple; by using passive solar heating you can keep your house warm and comfortable without paying anything extra for the electricity bill.
But to take full advantage of passive solar energy you need to do some planning while constructing your house.
As there is no need for any mechanical equipment in case of passive solar heating you will have to build your house in such a way that sun rays can enter the house in the winter season and not in the summer season.
Passive solar heating of the house is also dependent on the thermal mass of the interior of the house. Thermal mass refers to the ability of a material to catch, collect and produce heat.
Heat is absorbed by materials having high thermal mass like brick, stone, or tiles when the sunlight falls on them. And when the sun sets, these high thermal mass materials release the heat absorbed to keep the house warm during the night.
Advantages of Passive Solar Energy Heating
Here are some of the top advantages of passive solar energy:
- Passive solar energy is environment-friendly and thus a better option compared to other dirty and expensive fossil fuels.
- Utilizing solar energy helps in reducing carbon footprints.
- Helps to reduce electricity bill while providing heat using solar power.
- No need for any external power source.
- No need for any additional maintenance except for building maintenance.
- Floors and walls act as heat collectors so no additional collector is required.
Disadvantages of Passive Solar Energy Heating
Passive solar heating does also have some disadvantages that you can’t ignore. Here are a few:
- It is less effective than the active solar heating system (discussed later).
- Not being able to eliminate the heating bill completely still helps to reduce them to a great extent.
- Need a clear path to let sunlight enter into the house without passing through any trees or anything other on the path of sunlight.
- Heat absorbed cannot be converted into electricity to be used in any other application.
Let’s first have a look at the concept of active & passive solar heating & then we will compare active vs passive solar heating.
Active Solar Heating
Active solar energy heating on the other hand is a process that involves a more complex method to generate electricity from solar energy.
While passive solar heating only absorbs solar energy it does nothing more to enhance the energy absorbed. Whereas, active solar energy heating takes the help of mechanical equipment that in turn enhances the conversion rate of solar energy to heat.
But in the case of active solar energy heating, a solar collector is used which is a device that helps to store solar energy.
A solar collector collects solar energy and then converts them directly into electricity or other usable forms, e.g. water heating, PV Modules, etc.
Advantages of Active Solar Energy Heating
- A clean and environment-friendly system which also helps in reducing the carbon footprint
- Helps to reduce electricity consumption to produce heat thus helping to minimize electricity bills.
- It is more effective in case of conversion rate compared to a passive energy heating system
- Can be installed easily in any location.
Disadvantages of Active Solar Energy Heating
- Installation of lots of equipment like the solar energy collector, heat exchangers to produce heat and it makes a lot expensive.
- Needs regular maintenance and the maintenance charges of these types of equipment are also very high.
- Installed equipment takes a lot of space in the house.
- It also requires another power source to operate the pumps and fans.
Active vs Passive Solar Heating: The Comparison Table
Both active & passive solar heating have their own advantages & disadvantages.
But to know which one is best for you, we need to compare them based on efficiency, cost, maintenance & several other factors.
Here’s a comparison on Active vs Passive Solar Heating:
|Passive Solar Heating||Active Solar Heating|
|1.||Passive heating does not require any mechanical equipment.||In the case of active heating Solar collectors are required to collect solar energy. Along with that, some other types of equipment are also required to transport the heat produced.|
|2.||Proper planning is required before constructing the house.||Can be used in any house without any planning.|
|3.||Solar energy is collected within items and elements of the house are having higher thermal mass.||Solar energy is collected in a separate kind of collector.|
|4.||This system cannot be employed in every location. Only those places where enough sunlight is available throughout the day in winter can use this system.||This system can be used in any place without any problem.|
|5.||A passive heating system is less expensive as compared to an active heating system as there is no equipment needed to install or maintain.||Many expensive equipments are used and the cost of maintenance is also very high.|
In this post, we have discussed an in-depth guide about active and passive solar heating, along with their advantages and disadvantages. Additionally, we have also compared active vs passive solar heating.
After reading this article you will be knowledgeable enough about active and passive solar energy.
Finally, after knowing about both types of solar energy we can conclude that active solar energy is more effective than passive solar energy. But in terms of cost, passive solar energy heating is cheaper in comparison to active solar heating.
So, it is safe to conclude that both have their own usage as both types of heating use different methods for energy conversion.
What do you think? Which one among the two is best? Do let us know in the comments section – because your opinion matters!