Now that you’ve seen the best solar panels on the market, you might want to know what to look for in a solar panel. Below is an overview of some factors to consider when choosing a solar panel. It is not an exhaustive list but will help you know what to look for and what questions to ask installers.
Solar panels — sometimes known as photovoltaic (PV) panels — are a device that converts energy from sunlight into electricity. Solar panels are made of solar cells, which are usually crystalline structures made of silicone. The first three keywords refer to the material used to make solar panels.
Monocrystalline: Monocrystalline solar panels are made from one silicone crystal that is cut into multiple wafers to capture sunlight. The efficiency of monocrystalline panels is usually between 15-20% — which is good. The high efficiency of monocrystalline panels comes with a higher cost.
Polycrystalline: Polycrystalline solar panels are made from multiple silicone crystals that are melted and molded into a panel, then cut into wafers. The efficiency of polycrystalline panel is typically between 15-17% — which is good. Polycrystalline panels were made before monocrystalline panels and are therefore less expensive, but at a medium price..
Solar panel efficiency refers to how much sunlight is converted into usable electricity. Homeowners want solar panels with a high efficiency percentage. A good efficiency range is 15-22% — though high quality solar panels can now reach 23%, but less common. However, the higher the efficiency of a solar panel, the higher the price.
Before you decide on a solar panel, you should consider the energy requirements of your home. You might not need the best solar panels commercially available to power your home, just like you don’t need a sports car to get groceries. Besides efficiency, you should consider how much energy one panel can generate and how many panels you can fit on your roof. Think about how many watts a panel can generate and what is needed to power each of your appliances, lights and potentially your electric vehicle. Compare this to how much energy your home normally uses and what you want from your solar set up (saving money vs. going off grid).
The size and weight of a solar panel are important factors to consider. Your roof has limited space — especially limited usable space. Though size and weight vary from brand to brand, EnergySage reported standard dimensions for a residential solar panel are 66×40 inches for the panel, 1.25×1.6 inches for the frame and each panel weighs around 42 pounds. Another way to put that is a standard panel can be around 5.5 feet by just over 3 feet — with an area between 15-18 feet. Commercial solar panels are typically larger.
Solar panels can be a big investment for your home and can last 25-30 years. You want to make sure you can either see the full lifespan of your system or reap the increased value of your solar home when you sell.
When looking at reviews, try to see how long solar products can last. As a good indicator, you can also look at the warranty. The length of the warranty can give an indication of the manufacturer’s confidence in the solar panel product. Most manufacturers have a 25-year warranty for solar panels.
There are two main warranty types: a performance warranty and an equipment warranty. All electronic products degrade over time and a performance warranty guarantees if your panels’ performance deteriorates faster than normal, it will be replaced. EnergySage reported most warranties will guarantee 90% performance at 10 years and 80% performance at 25 years. An equipment warranty will typically protect your equipment for 5-12 years.
It doesn’t matter if you find the right solar panel if it’s installed incorrectly, damages your roof or experience untransparent pricing. Homeowners need to do their due diligence when looking for a solar installer. Besides looking at installer services, online reviews and asking friends or family members — compare quotes, ask for pricing information and see how long they’ve been in business.
A good rule of thumb is using an installer with more years of experience. When looking at quotes, make sure each quote specifies the the make and model of panels, inverters and batteries; pricing, total system size (kW), expected electricity generation (kWh), expected utility bill savings, total system costs before and after incentives, information on solar incentives, financing information and warranty information. Another must-have to help you visually understand your new system is a satellite photo of your home with the proposed layout.
Once you’ve made the solar investment for your home, you want to get the most out of your decision. Solar energy can both reduce your carbon footprint and save you money. Both benefits make solar panels an attractive option.
Size: The size of your solar panels and the number of solar panels on your roof are an important factor in energy generation. Depending on the efficiency of your solar panel, a larger solar panel will likely generate more energy. The good news is solar panels are often scalable and adding more panels to your rooftop can generate more power for your home.
Orientation: The direction your solar panels face is an important factor in energy production. In the United States, homeowners typically want solar panels installed on roofs that face south. The right orientation will expose your solar panels to the maximum amount of direct sun. The angle of your solar panels is also important, homeowners should aim for a tilt between 30 and 45 degrees to capture optimal sunlight. With the improper direction and angle, your home may not see the maximum amount of solar energy possible. EnergySage offers a great resource that helps homeowners find the optimal solar panel orientation for their latitude.
System Components: All technology is made of different components that contribute to the solar panel’s efficiency. If you’re not seeing optimal solar generation and savings from your solar system, there could be a problem with one of its components. If there is a component issue with your solar system, contact the solar installation company that installed your setup.
Sunlight: Solar panels convert sunlight energy into electricity, which requires good access to the sun. Sunlight accessibility does not just refer to the number of sunlight hours per day or the cloudiness level. Other factors that can impact your solar panels’ performance include dust, leaves, snow and shade from trees or buildings. It is important for homeowners to clean their solar panels once or twice a year to remove dust — more may be needed to remove snow, leaves or other debris.
System Temperature: Similar to leaving your smartphone in a hot car, solar panel systems experience lower efficiency as their temperature rises. High temperatures could be caused from extreme outdoor air temperatures or heat buildup from rooftop material.
Solar panels are an investment for your home and need to be maintained. Another great thing about solar is that panels require minimal maintenance from homeowners or small business owners. Despite the minimal maintenance required, it is important to maintain solar panels for optimal solar generation. A good solar panel setup can last 25-30 years and can pay for itself in five to 12 years.
Annual Inspection: Scheduling an annual inspection from a solar installer company in your area is a good idea. Hiring a professional solar inspector can help diagnose problems early or before they happen. The cost of an annual inspection could be around $150, according to Home Advisor.
Cleaning: Dust, leaves, snow and debris block sunlight from reaching your solar panel. Generally, it’s a good idea to schedule two cleaning appointments per year. For some homes, that could be once a year and for others, it could be four times a year. It’s generally better to hire a professional solar cleaning service to safely go onto your rooftop. The costs of a cleaning appointment can average $15-25 per panel for a home with 20-25 panels.. To save money, it is possible to clean your own solar panels but you will need the right cleaning and safety equipment. There are safety risks with cleaning your own solar panels and you should check your warranty stipulations.
Once solar panels are installed on your home or property, it is important to monitor its performance. Homeowners want to make sure their solar panels are working the way they intended. Before you make your purchase, you should know how much electricity your solar panels should generate on average. If you include a backup battery in your home’s setup, you also want to know your battery’s state of charge so you can depend on it.
We created Enact Home — a digital platform that helps homeowners track their solar performance. Using Enact Home, homeowners can track solar energy generation, financial outcomes and storage performance. Our key performance metrics provide you with independent analysis and personalized insights through easy-to-understand visual displays. Enact Home provides trust and transparency in your solar journey. Homeowners can find Enact Home on either the App Store, Google Play or use the desktop version.
The wonderful, yet frightening, thing about solar panels is that you have options. Homeowners have greater access to solar panels today due to a variety of brands, greater incentives and lowering costs of going solar.
Enact Systems understands that making the switch to clean energy is complicated, which is why we can create a custom solar proposal for your home. After a conversation with our energy experts, Enact can provide accurate proposal quotes for you using satellite imagery. You can choose the best product, installer and financing option that works for you. Afterwards, homeowners can use Enact’s digital platform to monitor and visualize your solar system’s performance.