Frequently Asked Questions about PV Systems
¿What is a Photovoltaic System (PV System)?
It's the combination of various electrical components that convert the Sun's energy into electricity that can be used and stored.
How many types of PV systems are there?
The grid-tied system is the most common because it's an investment for every client of the Puerto Rico Electric Power Authority (PREPA). This system permits you to produce your own electricity in parallel with PREPA. It's called grid-tied because it has to be interconnected to PREPA's grid, because it depends on the grid voltage in order for it to work. So, if the grid is down, the PV system will not work. But the system is designed to help you not pay for energy and fossil fuels to PREPA.
The bimodal system is the same as the grid-tied but with batteries and other battery-related components. You can produce your own electricity and have electricity when PREPA's grid is down. It's like a electric generator but with batteries.
The third system, the stand-alone, is the same as the bimodal but without the interconnection with PREPA. This system usually requires a larger number of batteries in order to supply the electric loads and for obvious reasons it's the most costly system of all three.
There are various, but the three that are the most common are: the grid-tied, the bimodal, and the stand-alone.
Does the system really work? A friend of mine had one installed in his house/business and it's not yet interconnected to the grid.
Now, the interconnection of the system has to go through a permitting process with the Electric Power Authority. But the process depends largely on the diligence of the installer / engineer, and the diligence of those of the Electric Power Authority. Our duty at Juapi Project Services is to be as diligent as possible.
Indeed yes. It works so much that Walmart, El Nuevo Dia, Sam's Club, different credit unions, and other people and companies have photovoltaic systems for their own electricity production. Remember that such large companies would not do projects that are not cost-effective, so you can rely on solar energy just as they have.
How does it work with the Puerto Rico Electric Power Authority in residential projects?
During the day, a lot of people are working or studying outside the house, but those are the hours that the PV system is producing electricity. So part of the electricity goes directly to the working loads (the refrigerator, some clocks, etc.) and the rest of the electricity is sent to the grid. But it will be accounted for by the electric meter, and will be accreditted to the electric bill.
In the evening, when people go home to turn on air conditioners, lights, televisions, etc., the energy produced by the PV system is sent back to the home.
With their Net Metering program.
How many solar panels do I need?
¿How much power and energy do I need? Check your electricity bills to see how many kilowatt-hours you use on a normal day. In the free consultation we can talk more about how much power you need in solar panels.
How much direct sunlight reaches your roof? You have to check if your roof has obstructions that cause shade and affects the production of the system, but do not worry because we can help you with that and there are ways to mitigate the shade.
Each place will be different depending on a number of factors. That is why our experts are here to help you with all the technical aspects of your project. So instead of thinking first about "how many solar panels do I need?", you should first consider the following questions:
Yes, it's the Credit Unions that currently offer financing specifically for photovoltaic systems. But some banks may also offer financing.
Do I have to mortgage the house with the loan?
Not necessarily, it will depend on the loan from the financial institution. Remember that these institutions lend money according to the client's reliability, the project, and other factors. Institutions are going to have a greater guarantee on the loan if the property is mortgaged, meaning that they may reduce the interest rate, but in many cases it's not necessary.
What are the warranties of the main components?
The inverters usually have a 10-year warranty for manufacturer defects, but there are some with 5 years, and others with up to 25 years.
The PV panels have a standard warranty of 10 years for manufacturing defects. They also have a second warranty which is that in the year 10, the panels will have 90% of the efficiency as when they were new, and 80% at year 25.
How's the system's maintenance?
Also, an electrical maintenance is recommended annualy. It consists of verifying all of the electrical connections and that all the electrical components are functioning properly.
Since it's a static system, meaning that it does not move, the maintenance is very simple. The PV panels should be washed with water and a soft brush or broom when necessary. It can be once a month or once every couple of months, it depends on the location and it's surroundings.
Do you take care of all system development and all permits?
Yes, we can take care of everything, but it will depend on the service contract that is agreed upon.