The main source of energy for all the planets in our solar system is the sun. Since its creation, our planet has used sun’s energy to power its natural processes. So, sunlight is the main reason why there is life on our planet.
In today’s world, scientists believe that sun’s energy is important for sustainable development, and is renewable as well.
Scientists have recently made photovoltaic and thermal solar cells which can help us in harvesting the sun’s energy to generate electricity. The efficiency of these cells have recently been increased due to the advances in the scientific field.
So, we can take away from the above mentioned point that there are two ways in which we can use the sun’s energy, photovoltaic and solar thermal energy. These use sun’s radiation to give us the desired results.
Solar thermal energy uses sun’s radiation to heat up a fluid that is further used in other processes. However, the working system of photovoltaic solar cells is very different. In PV cells, light is reflected from the surface of the cell, which absorbs the energy to generate electricity.
An advantage to the PV solar cells is that you do not require a separate turbine system to generate power.
Both of the solar power generation techniques are used around the globe, but they only contribute 0.8% to the total power generation in the world as of now.
Both solar thermal and PV systems are currently being used in residential systems. Countries are taking measures to increase the percentage of their electricity produced by solar power, and this number is increasing regularly.
In this article, we will talk about PV energy, the solar panels used in this process and the overall cost of these solar systems which are used to generate electricity.
Electricity Usage in Residential Buildings
Let’s take a look at the electricity usage in residential applications before analyzing the overall cost of getting together a PV solar energy generation system.
Usage of electricity depends on the climatic conditions of a country. This number is 11.7 MWh on an annual bases. It is 6.4 MWh in France, and only 1.3 MWh in China. When we calculate a global average, the average annual electricity consumption turns out to be 3.5 MWh per home.
Keep mind that solar energy is not always available. To get a full day coverage, you will have to use an expensive battery bank, or you will have to use a private electricity connection for the half of the day. With a battery bank, you will be able to run the most essential devices in backup battery power.
Things Used in a PV System
When you use a PV solar panel under the sun, it directly generates electricity from the sunlight due to its unique properties.
However, solar panels are only one of the important parts of a PV solar power system. These systems include solar panels, battery banks, charge regulators, inverters, and the wiring that connects all of the things together.
All of these components are vital for the usual working of a PV solar energy system, and they influence the efficiency of these systems as well. Knowing about all the individual components that make up this system is very important to know how this whole system works.
So, let’s take a look at why PV solar power systems are so expensive to install.
The PV Solar Panels
Materials like silicon are used in the production of PV solar panels. Silicon is the second most available element in the Earth’s surface.
Silicon works as a semiconductor, and is used in the production of electronic devices, however, it is also being used in the energy sector these days. It is the main component used in the making of solar panels.
Three different types of silicon is used in the production of solar panels. Monocrystalline is the most expensive, yet the most efficient type of silicon used in solar panels. This reduces the total land area that you will be needing to house the solar panels. However, it is notorious for dropping its efficiency in warm climate.
Polycrystalline silicon is less efficient as compared to monocrystalline, but it has the best price per watt of electricity generated. It also produces less waste than its counterparts, but responds to temperature in a poor manner as well.
Thirdly, amorphous silicon has a the lowest efficiency of all the three type of silicon used in solar panels. It requires lots of land area to produce small amount of electricity. That is why this type of silicon is just used to charge small devices like calculators and lamps.
Amorphous silicon also degrades faster as compared to the other two types. But it is capable to tolerating extreme temperatures.
Consider that you house needs 9600 Wh of daily electricity. If you are going to install cheap monocrystalline panels, you will need at least a 4500 W system to fulfill your electricity needs. This is calculated for the winter months, as winter is the worst case scenario for solar panels.
When we multiply 4500 W with the average cost per watt of installation, it makes around 3375 USD in only solar panels to fulfill your electricity needs.
The reason why a product made from cheap sand is so expensive is that sand needs to go through several phases in order to be converted into usable silicon. Quality of the sand produced in the chemical processes determine its price. The ongoing research on the solar panels also increases the price of solar panels. Over $110 billion was invested in 2018 for the improvement of PV panels. This investment is divided amongst the people who buy solar panels.
So, you can clearly see that solar panels contribute a lot in the overall cost of a solar power system.
The PV solar panels we just talked about generate DC current, but most of our appliances these days use AC current. This is where using an inverter comes in.
An inverter converts DC current into 50 to 60 Hz current. This depends on the country you live in. You will have to pay $50 to $120 per kW for one solar inverter. These are usually utilized to convert DC into 120V AC current. This type of current is needed for low power consumption devices used in our houses. However, larger devices like Air Conditioners and Fridges need a 220V solar inverter. The costs for these inverters range between $150 and $320 per kW.
These might seem expensive, but high complexity production is necessary in order to achieve good results and to meet the global safety standards.
Usually, the inverters are used directly below the solar panel array, but they can also be used in a room if you are only using them for a single home.
Battery bank is used to store extra electricity for usage in the time of need. These work at night, and in the days in which there is not enough sunlight present to power up your house. Their cost is calculated by the cost per Wh of electricity generated.
Proper wiring is also needed to connect the battery to rest of the component. There are different types of batteries that you can choose from.
Remember that you will also need a ventilation system to keep the batteries operating at a normal temperature. The whole system will also need regular maintenance.
Charge regulators regulate the charging process of the batteries. They help in improving the battery life of your battery bank.
You will also need a specific type of regulator that would work for every system, as not all the regulators work with every system. This depends on the overall energy generation of the system.
Regulators often cost around 50 to 60 dollars a piece. Your solar system will need 12 or more regulators depending on the total power generation. Regulators also keep failing, and you will have to keep changing them regularly as well.
We have discussed all the main components of the system, but there is also other components like wiring and charge meters. These components add to the total costs of your solar setup as well.
Works are needed in the solar setup to connect all the different components. As a rule of thumb, you can add 8% of the total cost of the solar setup. Also, you should keep measuring the total energy produced in order to calculate your return on investment. Also, you will have to buy an electric meter to keep track of the energy produced.
This is what you will need in order to put together a solar setup to generate electricity in your house. This type of investment is perfect to run all the essential appliances in your house whenever there is no electricity needed. Investing in a larger battery bank setup will give you more power whenever you will need it. But that will also increase the cost of the whole system considerably.