The problem of power cuts, with the right knowledge, can be alleviated with a simple solar power unit installed in the home or a office
In these days of energy challenges around the world, renewable energy sources like solar power are becoming increasingly important. Solar power is the conversion of solar energy from the sun into electric energy.
Solar power has been with us for a long time. But there were so many limitations to its adoption. Mostly, the cost of the components was prohibitive. With advances in the technology though, the cost of installing a complete unit has significantly reduced.
This is good news especially for poor folks in developing countries. And with people like Elon Musk and Solar City committing so many resources to research and development, the cost is going to come down further in the future.
For now, though, households and individuals, depending on available resorces budget can easily deploy this alternative source of energy to power electric and electronic devices. And in spite of the initial cost of installation, solar power is cheaper in the long run.
One of the arguments for renewable energy like solar power is related to global warming. With rising population and industrialization, the carbon footprint of the world is increasing geometrically.
The effect on the planet can be seen in rising global temperatures, unusual weather patterns, and disappearance of the ozone layer in the atmosphere.
Because of these, green energy as an alternative solution is growing in importance.
The logic is simple, to reverse the destruction of the planet, we have to reduce our carbon footprints. And one of the ways to do that is through the adoption of green energy sources like solar power.
Other green energy sources include wind, water, and geothermal energy.
In most of the word’s developing countries, green energy is not a serious concern. The issue is how to even get power in the face of epileptic supplies.
Solar power, therefore, can be a lifesaver in many cases. But so many don’t know how to go about getting it. And because of that, they waste money buying junk components.
This guide would take you through the process of installing a simple solar solution in your home.
Solar power components
A complete solar power unit for the home consist of the following
- Solar panels
- Solar charge controllers
Solar panels come in various shapes and sizes. The good ones are usually made to last for about 20 years before they become less efficient.
There are two popular types of solar panels in the market: monocrystalline panels and polycrystalline panels. Basically, monocrystalline solar panels are more expensive than polycrystalline solar panels.
In installing solar power in your home, some sellers would attempt to make you purchase polycrystalline panels at the cost of monocrystalline panels. So it is best to know the differences between the two.
The best way to tell them apart physically is to through the shapes and color.
Monocrystalline panels tend to be black or very dark in color while the polycrystalline cells have a bluish tinge.
Physically, and more impotantly, polycrystalline panels have perfectly rectangular solar cells while monocrystalline cells have rounded edges.
Having said that, homeowners with limited funds would be okay with polycrystalline panels because of the cost. But if you have enough funds, you might as well buy the monocrystalline panels as they are more efficient.
Solar batteries are very important in the set-up. The batteries are meant to store enough energy from the sun to be used for periods when there is no sunlight.
So the bigger the battery, the more energy you can store and the longer you can power your gadgets.
Also known as maintenance-free batteries because they are completely sealed, they can be found in the market either brand new or second hand.
One should be careful not to buy substandard batteries because there are so of many of them in the market these days.
Solar charge controllers or regulators are always installed between the solar panels and the batteries.
Basically, they are battery chargers. But more than that, they make sure the batteries are never overcharged by regulating the voltage and current coming from the solar panels.
There are two types of charge controllers
1. Maximum power point tracking (MPPT) charge controller
2. Pulse width modulation (PWM) charge controller
They are cheaper than MPPT charge controllers because they are not as effective in supplying power to the battery in the same time frame. With PWM controllers, you would need a longer time to charge your battery.
Both charge controllers come in different shapes and sizes. The capacity you buy depends on the capacity of the battery. In general, a charge controller with a higher rating would charge your batteries faster.
InvertersThe Inverters are attached to the battery. They convert the direct current in the battery to alternating current that can be used by gadgets and appliances
These too come in different sizes. What you need depends on the load you intend to power. So you better be careful you are not tricked into buying something you don’t actually need.
Calculating the solar panels to battery requirements
This is where most people get it wrong. Here is the basis of the problem: on the average, we get about 7 hours of sunlight every day. That means, your panels have seven hours to charge your battery daily.
Obviously, the more solar panels you have, the faster your batteries get charged. But due to cost, buying so many panels may not be feasible.
On the other hand, installing too few panels would mean never getting a fully charged battery during the day.
So to calculate the number/capacity of panels you need vis-a-vis the capacity of your battery, just follow this simple formular:
Battery capacity (Ah) ÷ [current rating of solar panel (amp) × hours of sunshine (7 hours)].
For instance, if you bought a battery rated 200Ah, and you want to buy 100W solar panels (each 100W panel has a cirrent rating of 5 Amp), you would need
200 ÷ (5 × 7) = 5.7 100W solar panels or approximately 6 solar panels
The current rating of solar panels are as follows
20W solar panel = 1Amp
40W solar panel = 2Amp
60W solar panel = 3Amp
80W solar panel = 4 Amp
100W solar panel = 5Amp
These figures are normally written at the back of the solar panel. But if they are not, just ask the seller for the capacity of the panel to get the current rating of each panel.
From the above calculation, it follows logically that you would need about 3 100W solar panels to fully charge your 100Ah battery in a day (for 7 hours of sunshine).
The above calculations are for those with 7 hours of sunshine daily. For those with more than that, the number of panels would be less of course.
Let’s hear your thoughts in the comment section if you have a solar power unit either in your home or office.