Solar power represents today a pretty tiny share in the global energy mix, but the situation could change in the future, where improved solar cells and advanced energy storage devices would make solar energy a main source of power for our civilization.
The threat represented by global warming and the changed weather conditions, have ignited mankind’s interest towards clean sources of power (solar energy and other sources of renewable energy), because fossil fuels are finite resources and their global use for energy and heat production has lead to a massive air, water and soil pollution on the planet.
Being part of the renewable energy sources (sources of energy that are continuous), solar energy is considered today a main source of power for the future of mankind where along with the other sources of clean and renewable energy would replace all the energy generated by fossil fuels like coal, oil and natural gas.
The Future Of Solar Energy Is More Than Bright
Solar energy is produced today by turning the sunlight into clean electricity using the photovoltaic effect (solar PV cells), and without releasing any emissions.
We are also using large mirrors to concentrate the sunlight into a focal point where an agent (molten salt) is heated at temperatures exceeding 500°C (932°F), to produce steam and spin a turbine that will generate electricity with the help of a large generator.
The future for solar energy means for us: more residential installations of solar PV systems, cheaper and improved solar cells (higher efficiency) that will also live longer, advanced batteries (with increased storage capacity for solar energy), and a wide spread of the solar modules on every building that has Sun exposure to produce free and clean electricity for the people living in those buildings.
What Are the Current Uses of Solar Energy?
Today, we are using the power of the Sun in many ways.
Active solar uses
Active solar uses refers to the use of the sunlight to generate clean electricity using photovoltaic (PV) solar cells.
1. Charging portable devices
Small solar chargers consisting of one or two solar cells and a battery, are used today to power small devices such as a smartphone, an iPod and even a GoPro camera.
Larger solar chargers consisting of three to five solar cells and a stronger battery are used to charger larger devices such as a laptop, a tablet, a DSLR camera, etc.
These solar chargers can be sewn into backpacks, and by using them you can extend the life of your devices outdoors.
2. Outdoor Lighting
From Walmart, people are buying solar decorative lamps to illuminate the driveway inside their yard and garden.
Street lighting poles based on solar have become very common today because they are illuminating the streets using free and clean electricity provided by the Sun.
3. Gate Openers
Underground electricity can be pretty expensive to install, especially if the gate is located pretty far from the house.
Giving the fact that the energy provided by the Sun is free, many homeowners are using one or two solar panels installed near the gate, which are providing the energy required to open and close the gate.
4. Fountain Pumps
An outdoor living space requires the presence of the water provided by a fountain.
Due to the fact that many fountain pumps are 12 Volt DC, instead of using energy from the grid, many homeowners are using a solar panel to produce the energy required for pumping water.
5. Electronic Signs
Nowadays, many construction signs are powered by solar energy.
Giving the fact that these road signs consume a small amount of power, installing road signs with one or two solar panels above is a great solution to avoid construction and utility costs.
6. Remote Communications
In many remote areas of the planet, the grid is not an option, and in order to ensure a communication line (military, science, remote exploration), small solar panels are used to produce the required energy for powering all the devices used for communication.
7. Solar Cooking
Solar cooking is a great solution when camping outdoors and there is a fire ban at campsite.
Using the sunlight to cook is also a solution when you are outside in nature and you don’t have fuel to cook your meal.
Using reflectors and concave mirrors, you can concentrate the sunlight to boil water, and even to roast a turkey.
8. Water Heating
To heat water in a more efficient way, many homeowners are using solar water heaters that work very well during the summer, and even during the winter when the Sun is less strong.
A solar water heater can preheat your water during the winter, which means that your electric water heater will work less (you can save a good amount of energy and money by using a solar water heater that works even during the winter).
9. Attic Ventilation
During the summer, your attic radiates heat into living space, which means that your AC unit (Air Conditioner) will work more to cool the rooms.
Having an attic fan that removes the hot air from the attic is a very good idea to lower the energy consumption of your AC units.
Using a solar powered fan is another great idea to cool the attic using clean energy provided for free by the Sun.
Passive solar uses
The power the Sun can also be used to heat your home in a passive way.
1. Passive Heating
By positioning the house to receive heat from the Sun during the winter months, you are using the Sun’s power to passively heat your home.
This activity also requires special windows, and materials for flooring and walls.
During the summer, you will block the heat coming from the Sun to ensure that your home remains cool.
A passive home consumes only a small amount of energy during the entire year because relies on the Sun to heat the well insulated house during the winter, and uses a ventilation system that removes the hot air from the house during the summer.
The power of the Sun is used to heat the house during the winter, and during the summer, the Sun is blocked to avoid overheating the house.
Future Developments in the Solar Sector
The Sun represents such a powerful source of energy that it could potentially provide more energy in just one hour than our entire civilization uses over a period of one year.
This extremely powerful energy source is not only clean, but is also virtually unlimited and will last billions of years.
In order to make solar energy a main source of power for our civilization, the solar cells used to turn the sunlight into electricity need to become more efficient and much more affordable.
The best commercial solar panels using solar cable 4.0mm have an efficiency of around 20 percent, and a price of around $0.85 per watt to $1.25 per watt.
Price per watt is falling
By 2022, the price per watt is expected to drop to just $0.22 per watt.
The majority of commercial solar PV cells (both mono and polycrystalline) sold today are single junction solar cells (they are made from a single material).
The problem with these single junction solar cells is that they can only capture energy from a particular segment of the spectrum of light, which means that the maximum theoretical efficiency of a single junction solar cell is around 35 percent.
The highest PV cell efficiency ever achieved was 46 percent and was developed 2014 by teams of researchers from France and Germany.
They achieved such a high efficiency by creating a multi junction solar cell based on multiple materials.
Highly Efficient Solar Cells
For multi-junction solar cells, the maximum theoretical efficiency is around 87 percent.
For now, multi-junction solar cells are only used in the space technology (Mars rovers) because they are too costly for mass production.
Another emerging solar technology is organic photovoltaic cells (OPV), and these are made from hydrocarbon materials (plastics).
These solar cells are considered more environmentally friendly compared to silicon-based cells.
Solar Cells Made Of Plastic
OPV’s are made of plastic, and this means that they are flexible and can be used on curved structures (sewn on backpacks as portable power banks using the Sun’s energy).
OPV’s efficiency is around 13%, but researchers from the University of China, have developed and OPV cell with an efficiency of 17.3 percent, by incorporating a tandem cell system, which is similar to a multi junction PV cell (captures multiple wavelengths of light (uses devices built within the same cell structure).
To be compared with the silicon-based solar cells, OPV’s need to become more efficient and more durable.
Concentrator photovoltaics (CPV’s), is another emerging technology using lenses or mirrors to focus a large area of sunlight onto a small area of multi-junction solar cells.
Lenses and mirrors are cheaper, and by using them we can maximize the production of energy of costly multi-junction solar cells.
However, when we talk about solar photovoltaic cells, we need the presence of the sunlight to produce energy, which means that during cloudy or rainy days, CPV technology won’t work.
Final Conclusion
The Sun is here to sustain all life processes on our planet, but also to power our civilization with clean and free energy that could remove the need of utility companies, and will turn every house into a small power plant using solar panels or other renewable energy source.
At the end of 2019, solar energy accounts for only 1% in the global energy mix, but by 2050 it could account for more than 50%.
To make solar a major source of power for our civilization, we need to increase the efficiency of the solar cells, lower the prices of the technology, increase the generation capacity for solar, and create improved storage devices that could save a very large amount of energy for days and even weeks of usage.
