Introduction
Rooftop solar installation or residential solar installation is simply defined as utilizing solar panels as accessory or construction material for buildings to produce electricity. The rationale behind this idea is to cover partly or entirely the energy demand of a building. Generally speaking, in the case that solar panels are used as an additional material that is added to meet part of the electricity demand of a building, the system is often called building applied photovoltaics (BAPV). If PV modules are considered as a material of construction that meets partly or entirely the energy requirement of a building, they can be categorized as building integrated photovoltaic systems or BIPV. BIPV is a relatively new trend in urban areas and the building sector compared to BAPV. BAPV has been one of the attractive solutions to take steps in line with the mitigation of devastating effects of climate change since the early years of the commercialization of solar panel technology. In this article, we aim at investigating and finding the criteria for choosing the best solar panels for home use.
First of all, let’s list up the frequently asked questions to design BAPV:
- How much of your electricity demand is going to be supplied from the solar system?
- How much do you allot for your solar system? (budget amount)
- How much of your space do you want to use for the solar system (rooftop, parking, facade…)?
It is obvious that this list of questions is neither the complete one nor arranged by the importance of priorities. Because there are a lot of conflicts of interests and priorities among people. For instance, some people prefer to cover a larger slice of their electricity bills from their solar panel systems. While others pay more attention to the appearance of their houses and do not want these facilities to become an eye soaring issue and allot limited space to them. But when you decide to do this work, suddenly find out there are a lot of things that you should know and read about them and this point may lead to a reduction in your willingness and enthusiasm. Here, we present and discuss how to choose the best solar panels and what criteria can help you to choose the best solar panels for installation.
How Can You Choose The Best rooftop solar?
In order to choose the best solar panels for house use as a house owner the most common and straightforward criterion which comes to mind is efficiency. Maybe, at the next levels, the power output of solar panels and their duration of warranties are considered as criteria for selecting. But the question arises here which criteria are more important and essential for choosing the best PV modules?
Common Criteria for Selecting the Best Solar panels
Here, we introduce factors that have been suggested by others such as EcoWatch and Climatebiz, and then propose our preferred ones. EcoWatch has considered efficiency, durability, warranty, price point, and temperature coefficient as its main factors for comparing different PV modules [1]. Efficiency is the ability of the solar panel to convert sunlight into electricity. In simple words, this means the higher the efficiency, the more electricity is generated for you [2]. It is worth mentioning that the performance analysis of PV modules in the near and long-term is usually referred to as reliability and durability in the literature [3]. Solar panels are always designed for being in operation for 25-30 years depending on the careful choice of materials by PV module manufacturers. Although, their performance is only warranted for 10 through 12 years. It is usually referred to as the performance warranty of the solar panel. In other words, There are two main types of warranties for solar panels. The first one is a product/workmanship warranty and the other is a performance warranty [4]. The product warranty covers the actual panels against defects, equipment failure, and environmental conditions (like high temperature, UV radiation, or humidity). A performance warranty ensures a minimum base of electricity production is maintained during the warranty period. The product/workmanship warranty is what EcoWatch announced to consider to distinguish solar panels from each other. The price point is the solar panels cost that can fluctuate based on many factors [1]. As another factor, EcoWatch has put forward the temperature coefficient. Lower minus temperature coefficient means having a better performance for a solar panel in higher temperatures compared to other ones [2].
Other Common Criteria Which Sometimes Suggested By Experts
Climatebiz talked about the price per watt (PPW) of solar panels instead of the price point or the final price of the solar panel [5]. But, other factors remain the same. PPW factor is usually defined for a completed solar system including solar panels, battery pack, structure, racking components, etc. which are installed on the roof and it is not limited to calculating only the price per watt of the solar panel [6]. For example, a 5kW solar system has 5000 watts. If that system costs $15,000, then the cost per watt is ($15,000 / 5000W =) $3/W [5].
Another used criterion for distinguishing and categorizing solar panels is power density. The power density is the total power generated by a PV module divided by the area of that module. The power density unit is watts per square meter (W/m2 ) [2]. It is one of the things that all PV module sellers, buyers, and installers should consider.
What Criteria Are Suitable for Choosing Best Solar panels for Your Home
SolarEdition thinks that the minimum and optimum criteria for choosing the best solar panels are the price per watt of solar panels and power density. Power density can be easily calculated by using the dimensions of a solar panel from its datasheet and then dividing the power output by the product of multiplying the length and width of the solar panel. The price per watt of a solar panel is derived from dividing its price by its power output. knowing price per watt and power density is necessary for comparing different solar panels. In other words, a solar panel with a higher power density and lower price per watt can be a better option among others.
It is important to note that the global rooftop solar installation reached 59 GW capacity at the end of 2021 and will surge close to 100 GW by 2025 [6]. It demonstrates the considerable share of this segment of solar power and persuades PV module manufacturers to produce products with better power density without increasing the price.
Did you know?
Solar Edition publishes the top 10 solar panels monthly since 2019. In addition to this, we also publish a top 10 72 cells solar panels for industrial-scale every quarterly (Q1,2,3,4).
Author: Hesam-Edin Hayati Soloot & Amir Hayati Soloot
References
[1] EcoWatch, “10 Best Solar Panels for Homes (2022 Review)”.
[2] SolarEdition, “Top 10 Solar Panels – February 2022”, written by Hesam-Edin Hayati Soloot & Shahab Moghadam.
[3] SolarEdition, “What Material Protects Solar cells from Harsh Environmental Conditions in PV modules”, written by Hesam-Edin Hayati Soloot & Amir Hayati Soloot.
[4] GoingSolar, “What is a solar panel warranty?”
[5] Climatebiz, “10 Best Solar Panel Manufacturers In The World”.
[6] TaiyangNews, “Rystad Energy Says Annual Global Rooftop Solar Deployment To Nearly Double Within 4 Years”.