Solar energy is an inexhaustible source of energy that is available to all human beings. Next we will talk about passive solar energy, its benefits, uses and definition.
What is active solar energy?
Active solar energy is the use of sunlight to produce electrical or mechanical energy through the use of certain technologies or equipment. These can be water pumps, fans, solar panels or collectors, among others.
Today, and thanks to the interest of governments and citizens in seeking renewable energy sources, the interest in active solar energy is growing every day .
Active solar energy is one that uses technologies that allow the sun’s energy to be transformed into accumulative heat or electrical energy. It is mainly used to obtain domestic hot water or for heating. Currently, due to the need to search for renewable energy sources, active solar technology is booming. But what benefits and applications does it have? In this article we are going to answer these questions.
active solar energy applications
Active solar energy, as we have explained, is that technology that uses systems that allow the use of solar radiation . Either to obtain domestic hot water or to transform it into electrical energy . It is also possible to produce an air stream for ventilation or cooling or heat storage for later use. This is the case of pumps or fans. When devices that allow the capture and storage of the sun’s energy are not used, we speak of passive solar energy . This system consists of adapting a house to be able to maximize the immediate use of the sun’s heat. It is also an alternative energy.
Active solar energy, in addition to being solar heating systems, or alternative solar heating systems, also make it possible to obtain domestic hot water. Even those that use a thermosyphon system , and those that use a pump to circulate the water are part of the active solar energy . Another important aspect of active solar energy is the support system used. Generally, solar panels, which are the most common method of use, are usually placed with fixed supports. They are located facing south and thus collect solar radiation throughout the day. However, if solar trackers are used, the panels would perform a displacement that would improve their performance.
We are going to know below what types of active solar energy we can find and how they are applied to homes and other purposes. We refer to the solar panels that are placed on flat surfaces, either on the roofs of houses, terraces or on esplanades intended for this: photovoltaic active solar energy and thermal active solar energy.
1. Photovoltaic active solar energy
Active photovoltaic solar energy is one that is responsible for directly transforming solar radiation into electricity. Thanks to a semiconductor device called a photovoltaic cell, or also through a thin-film substrate called a solar cell. Currently, photovoltaic active solar energy is used in homes to provide active solar heating. Although the electricity supply is not completely dispensed with, self-consumption is greatly enhanced and the amount of bills to be paid is reduced .
Within thermal solar energy we find three types of collectors. The higher the temperature of these, the greater the applications they have. Thus, we distinguish between low temperature, medium and high temperature collectors.
The first are those that work at a maximum temperature of 65º. As a general rule, these are usually enough to supply the needs of a traditional home. When the demand is greater, those of medium temperature are used. In these, it rises between 100º and 300º. The reason is that an extra layer is placed on top of the collector which allows a greater amount of heat to build up. Lastly, high-temperature collectors for active solar thermal energy can reach temperatures above 500º, which according to the models reach up to 1000º.
Differences between active energy and passive solar energy
The most outstanding difference between active and passive solar energy is that active solar energy requires transforming the energy captured through the use of an external installation , while passive solar energy takes advantage of solar radiation directly.
Solar photovoltaic and thermal technology are part of active solar energy. The first uses solar panels to convert sunlight into electricity , while the second uses collectors to transform it into heat.
Passive solar energy uses specific construction techniques to take advantage of solar radiation, but without transforming it . For a property to achieve energy savings with passive solar energy, the process must begin from the architectural design or through restoration of pre-existing buildings.
An example of how passive solar energy works is bioclimatic architecture , which takes into account climatic conditions and the use of available resources, to reduce the environmental impact and try to reduce energy consumption.
Another difference between the two is that active solar energy can be stored . In contrast, passive solar energy must be consumed immediately.
In order for passive solar energy to be energy efficient, it needs to be combined with active solar energy .
Types of active solar energy
There are two types of active solar energy that are known and applied today. Namely:
Photovoltaic solar energy allows the transformation of solar radiation into electricity through photovoltaic cells .
It is obtained thanks to this semiconductor device, made up of a thin layer of phosphor and crystalline silicon, materials that directly capture sunlight and ionize and release electrons. The sum of all these electrons generates what we know as electrical energy .
Solar panels are attached to roofs and other surfaces with fixed brackets. They are installed with a specific cardinal orientation, depending on the geographical location in which they are located, so that they capture the greatest possible amount of solar radiation during the day .
It should be noted that one way to improve its performance is through the installation of solar trackers .
Currently, photovoltaic solar energy is used in homes, businesses, neighborhood communities, farms, orchards, solar plants and even in space. About 3% of the world’s electricity demand is supplied by the photovoltaic sector .
Solar thermal energy, for its part, takes advantage of the properties of thermodynamics to increase the temperature of a fluid and, therefore, its heat energy .
It requires the use of collectors to capture solar radiation and convert it into thermal energy. It is used for heating or for hot water supply .
Depending on the type of solar collector, collector or collector used, there are three types of solar thermal energy .
These devices use direct solar energy and operate at a maximum temperature of 65°C. If the demand is not very high, they are ideal for residential use.
They operate at a temperature ranging from 100°C to 300°C. They are used in homes that require a higher demand . In order for these devices to raise the temperature, an extra layer is placed on the collector to allow greater heat accumulation.
These collectors reach temperatures of 500°C and some models reach up to 1000°C.
Depending on the use that will be given to them, there are also several types of collectors :
- Flat solar collectors.
- Unglazed thermal solar collectors.
- Vacuum solar collectors.
- Solar collectors with radiation concentration systems.
- Sensors with sun tracking systems.
There are many benefits that the use of active solar energy provides both users and the planet. Among the most prominent are:
- Active solar energy is green, inexhaustible and free energy , since it comes from the sun.
- It allows to reduce the costs in the electricity bill .
- Its use has no impact on the environment because it does not emit greenhouse gases, which makes it a viable option to fight against climate change.
- Maintenance costs are low .
- It is a long-term investment . An installation of solar panels has a useful life between 25 and 30 years.
- They improve and increase the value of real estate .
Applications and uses of active solar energy
Active solar energy is mainly used to obtain domestic hot water, heating systems and to transform solar radiation into electrical energy .
Active solar technology is also used to produce air currents for ventilation or cooling and to store heat for later use. In any of these processes the use of pumps and fans is required .
Other uses of active solar energy are:
- Water purification.
- Solar batteries.
- Solar panels.
- Energy for public lighting, traffic signals and highways.
Do you want to know a little more about photovoltaic solar panel installations? Book a free consultation at Svea Solar and we will help you generate your own energy. Check it out for yourself!