The Homeowner's Guide to Solar Energy/Solar Panel Systems

With our country's inflation rate rising to a 5-year high, many of us have been desperate to find a way to somehow save up on some of our regular expenses. One way we can achieve this is through a solar energy or solar panel system, which helps us save on our monthly electric bills. Investing in a solar energy or solar panel system is a big step, and from a business point of view, it is important that you first learn everything that you know about it before making that big decision.

Before anything else, what is a solar energy or solar panel system?

A solar energy or solar panel system is a power system designed to supply electricity through the use of solar panels. It has 2 main components:

Solar Panels

These devices convert sunlight to DC electricity. DC electricity is basically just the same type of electricity produced by batteries, with positive and negative poles. The other type of electricity which is used on our homes is called AC. Notice that our outlets on our homes don't have positive and negative poles which is why we can plug our appliances in any orientation.

Solar panels have a rated lifetime of 25 years. This is specified by the manufacturer's Performance Warranty. This document tells the end-user how much the solar panel's output will be after 25 years due to degradation. Most of the top and best solar panels have a performance warranty of 80% of the total rated output after 25 years. These solar panels are expected to produce electricity until 30 years of its lifetime.

Since the solar panels have a long lifetime, as a homeowner, it is best to make sure of the quality of the solar panels that will be installed on your roof. Cheap, low-quality solar panels most probably wont last that long and is not worth your investment. As a saying goes: "The bitterness of poor quality remains long after the sweetness of low price is forgotten". Even worse, low quality solar panels even pose additional hazards to you and your home.

Solar Inverters

Since solar panels produce DC electricity, we need a device to convert this to AC electricity, which is the type we use on our homes. The solar inverter does this for us.

There are 2 main kinds of solar inverters used for residential solar energy or solar panel systems:

a.) String inverters - the most common type of solar inverter used for residential solar energy or solar panel systems. It is called "string" inverter because the solar panels are first connected in series to form "strings" which are then connected in parallel to the input of the inverter (see image below).

String inverters used in residential solar energy or solar panel systems are usually in the range of 1-5kW with 1-2 strings as input. They are wall-mounted like the image of the inverter above, so you will need to allot an extra wall space that is protected from the elements (sun and rain). The lifetime of string inverters is 10-15 years, so since the lifetime of the solar panels is 25-30 years, you will need to replace the string inverter once over this period. This is important for you to know as the additional cost for the replacement of the inverter must be considered in the 25 year financial analysis presented by solar installers.

b.) Microinverters - as the name suggests, microinverters are "smaller" solar inverters. On the picture on the left, it is the small black device that the installer is holding. It is mounted beneath the solar panels on your roof, so you don't need to allot an extra wall space on your home to mount them. These microinverters can accomodate 1 or 2 solar panels depending on the model. Microinverters also have a rated lifetime of 25 years, so replacement during the lifetime of the solar panels won't be needed.

The most important advantage, however, of microinverters is regarding how it operates. For string inverters, remember what we discussed about connecting the solar panels in series to form strings? Once we do that, each string then works as a single unit. All solar panels in the string produces only as much as the least producing one. For example, if you have 10 solar panels in series and one of those is shaded(by blown trash, etc.) the shaded solar panel will suffer a reduction in output. But since they are in a string, every solar panel in it will also suffer the same reduction in output. For microinverters, on the other hand, every solar panel works independently of each other. One shaded solar panel will not affect the others.

How Can We Save From Our Electric Bill Using A Solar Energy or Solar Panel System

The manner on how we save from our electric bill using a solar energy or solar panel system depends on the type of solar energy system that we will have. Primarily, there are 2 types of solar energy or solar panel systems:

1.) On-Grid - this type of solar energy or solar panel system is connected in parallel with the grid. You will have 2 sources of electricity, your solar energy system and the grid. Your electricity bill is lowered since you will then get some of your electricity supply from the solar energy system when it is producing energy(in the morning).

2.) Off-Grid - with this type of solar energy or solar panel system, a utility supply will not be needed anymore since the off-grid system will be your electricity supply. It will be able to accomplish this through the use of batteries (mostly for your night time consumption). So with this system, you won't pay for your monthly electric bills anymore.

Which Type Is Right For Your Home?

Most of the solar panel installations are On-Grid systems. This is because it has many advantages over Off-Grid systems. It is cheaper, less complex, easier to maintain, among others. The bottom line is, the cost of Off-Grid solar energy systems is not yet cheap enough to replace our utility grid.

FAQ About Solar Energy/Solar Panel Systems

"Can a solar/PV system run an air-conditioner(or any other appliance)?"

The question only becomes relevant for Off-Grid systems because it will only be your only electrical supply and therefore, it really must be able to run all of your appliances. For On-Grid solar systems, if it produces less than your total consumption, it just gets the deficit from the utility grid. So, with an On-Grid system, you must only think about how much of your total consumption do you want to offset using it.

"With a solar energy or solar panel system, will we still have power during power outages?"

For an Off-Grid system, you will definitely still have power since you will not be relying on your electrical grid anymore. For On-Grid systems however, during power outages, the inverter shuts down the whole system. This feature is known as anti-islanding and is a requirement by local utilities. This is so that electrical workers working on the line during a power outage won't be electrocuted by your solar energy or solar panel system.

"Does having solar panels on my roof increase the risk of lightning strikes?"

Having solar panels on your roof increases the chances of your house being hit by a lightning strike but only by a very insignificant amount. If you have an antenna on your roof it won't even increase the chance of your house being hit by lightning at all, since lightning will still most likely hit your antenna rather than the solar panels.

Being an Independent Power Producer Through a Solar Energy or Solar Panel System

Energy has always been produced in large, centralized power plants and because of this, it has also always been a few capitalist’s cash cow. Today, it is different. We now have the power to produce our own energy right on our very own roofs through solar energy, effectively making us independent power producers. And this is exactly what we can use to lessen our dependence on these large power plants.

One of the major benefits of being an independent power producer through solar is that the rising electricity prices basically don’t affect the electricity that you produce. This is on top of the monthly savings that you would get from the electricity that you have bought from the utility grid, but instead taken from your own solar energy or solar panel system.

Philippines’ Solar Energy Resource

Germany, a country that has invested very heavily on solar energy in the last few decades, from time to time, experiences days where the electricity prices become negative because of too much production. This basically means that the consumers will be paid to consume electricity. What’s surprising is that Germany’s solar energy resource is quite low compared to other countries’ and even only half of what we have here in the Philippines.

If Germany can utilize solar energy that effectively, we most certainly also can!

Imagine a Solar Powered Philippines

Imagine our country where most of the energy consumption is produced right on the very houses of the families living on it and not controlled by the few rich and powerful people. Imagine a very progressive country where all industries thrive because they are not burdened by high electricity prices. This is the country that we could and should be.

Be Part of a Solar Energy Revolution Today!

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Engr. Jet Andal has 6 years of experience in the design and installation of residential, commercial and utility-scale solar PV systems. Together, and with the use of solar energy, let us help make the world a better place. You can click here to read all of our other blogs. For aspiring solar PV engineers, you can also check out his Solar PV Engineering Ebook on Amazon on this link.