Solar power can be considered today the main source of renewable energy that can replace the conventional energy produced by fossil fuels in the next decades.
What is Active and Passive Solar?
To generate solar power (clean electricity) in an active way. Mankind uses today PV (photovoltaic) solar panels that are converting the sunlight into electricity (through the photovoltaic effect), and large mirrors that are concentrating the sunlight (CSP technology) into a point located at the top of a tower to heat an agent (molten salt) and generate steam that will spin a turbine to produce electricity using a generator (solar thermal power plants).
The CSP (concentrated solar power) technology also uses large parabolic mirrors that are concentrating the sunlight into the focal point of the mirror where a tube filled with a liquid is located.
The heated liquid reaches a temperature of about 400°C and generates large amounts of steam that are spinning a turbine and generate electricity using a generator.
A solar power plant using PV solar panels can generate electricity only when the Sun is up (during the day), but a solar thermal power plant using the CSP technology, can generate electricity even during the night by storing the heat (produced during the day) in molten salt, and taking that heat to produce steam and generate power when needed.
Passive solar refers to the use of the sunlight to naturally illuminate and heat a house. To use the sunlight in a passive way, the house must be placed in a certain position towards the Sun. This way, the house will receive the sunlight during the winter to help the central heating system and also to illuminate the different rooms in the house in a natural way (without using electricity and light bulbs), which saves energy and money monthly.
Solar Power Advantages and Disadvantages
Solar power is produced by the Sun, which means that this form of clean energy has more advantages than disadvantages.
1. Is a Free, Clean and Sustainable Source of Power
Producing electricity using solar panels is always considered clean because it does not produce any form of air, water or soil pollution.
Switching to solar is both beneficial for the environment and for our wallet because generating our own energy using the power sent for free by the Sun can reduce our carbon footprint and can also lower the energy bills paid monthly.
Using only the sunlight to produce electricity will preserve other natural resources of the planet for generations to come.
2. Is a Renewable Energy Source
Solar energy can be considered a renewable resource of energy only because the Sun will be here sending us light, heat and energy for free for another 5 billion years from now on.
By comparing this very long period of time (billions of years) with the time spent by mankind here on the planet, we can say that solar power is a never ending source of electricity.
Also, when the Sun will become a red giant or a supernova, our planet will be entirely destroyed, and I hope that by then, mankind will already be spread on many other planets in the universe.
3. Can Provide Energy Independence
The Sun is available everywhere on the planet, which means that we can use this awesome renewable resource to generate our own electricity even in remote areas of the planet where the grid is not available.
Using solar power you can produce your own power, which means that you can pay less on energy bills, or you can make some money (getting paid by the utility company) for the excess energy sent back to the grid.
To become energy independent, you only need a small solar PV system (one or two PV panels) that can power at least your gadgets and a few light bulbs (preferable LED light bulbs) and you will start realizing how easy is to generate power without relying on the grid and the utility company.
4. Is a Continuously Evolving Technology
Scientists are working hard today not only to improve the efficiency of the solar panels, but also to make solar cells that are producing energy during cloudy and rainy days or in the evening.
Conventional solar PV (photovoltaic) panels are producing a decent amount of energy only during the day when the Sun is up and there are no clouds to block the sunlight from reaching the surface of the planet.
This is the reason why scientists have created solar cells that can generate electricity even in the evening or in the cloudy and rainy days, which makes solar power more reliable.
5. Solar Panels Are Built To Last for Decades
The solar panels available today on the market, are built to withstand very strong winds (high winds produced by hurricanes), strong tropical storms, hail and snow.
Maintenance is minimal, but from time to time you have to clean your panels (or pay somebody else to do it) from dust and any debris (twigs and leaves), which can block the panels and reduce the energy production of the panels.
6. Reduces Our Dependence On Fossil Fuels
Any new solar PV system installed on the rooftop or in the yard becomes a source of renewable energy that saves coal or another fossil fuel from being burned for energy production.
This is not only preserving the natural resources of the planet, but is also helping to reduce the level of air, water and soil pollution on the planet for a clean and healthier environment for us and the future generations.
7. Solar Market Provides Today a Variety of Financing Options
Before jumping in and purchasing a solar PV system, you should always weigh in all the financing methods available on the market because directly purchasing the PV system was more popular in the past, while today, leases, loans and Power Purchase Agreements seem to provide more options for the clients.
Disadvantages of Solar Power
Like any other new technology available on the market today, solar power has a few drawbacks, which need to be overcome to see a wide spread of this clean technology on the entire planet.
1. Solar Panels Only Work During the Day
Solar power is a great source of free, clean and renewable energy that works only during the day, and produces the most amount of power only during the summer when the Sun is very strong and the sky is clear.
Scientists have already created solar cells that can generate electricity even during the evening or in the cloudy days, but there are no solar cells that can produce energy during the night.
For homes using grid-tied solar PV systems, (solar panels systems connected to the grid) there is no energy anxiety during the night or during consecutive cloudy or rainy days because when the panels are not producing energy, they simply use the energy provided by the grid.
However, for an off-grid home that relies only on solar panels and the energy stored in the battery system, energy anxiety appears during the cloudy or rainy days because the capacity of the battery is limited, but the energy demand of the house is the same.
To overcome this issue, off-grid owners usually use a generator (which pollutes) to recharge the batteries.
2. Excess Energy Produced by the Panels
The homes that are using grid-tied solar PV systems do not store the excess energy produced by the panels because that energy is sent back to the grid to power the neighbors.
However, the amount of money paid by the utility company for the excess energy sent back into the grid is lower than the money paid by the owner to receive the same energy from the grid.
3. A Solar PV System Involves High Upfront Costs
It is true that solar energy becomes cheaper every year, but even so, the amount of money paid even for a small solar PV system is quite high.
All the components of the photovoltaic system such as: solar panels, electrical connections between solar panels, power inverter, charge controller, wiring, mechanical mounting equipment, electrical meter (for grid-tied systems), etc., are adding to the overall amount paid initially to purchase and install the solar PV system on your rooftop.
However, once installed the PV system will generate free and clean electricity for decades to come requiring only a minimal maintenance service from your side or from the company that installed the system.
Final conclusion
Solar energy is becoming more popular and a desired technology by an increasing number of clients today.
This means that even if building large solar power plants is a slow and difficult process due to the major investments required, the increasing number of solar owners in the U.S. starts to improve the share of solar power in the energy mix of the cities, which lowers the level of air, soil and water pollution and improves the life of the people living there.