The fierce winter storm that crippled the country and left millions of Texans without power or water has sparked a lot of discussion around solar as a reliable solution for our energy needs, especially when connected to backup power storage.
Naturally, several questions on the subject came up almost immediately from those affected by the recent storms:
We’ll help break each question down for you with honest answers based on facts. Keep reading.
Do Solar Panels Work in the Winter?
MYTH – Solar panels do not work in winter
FACT – Solar is a reliable source of energy during winter
It’s not the heat of a sunny day that activates solar panels; it’s simply the sunshine. A photovoltaic solar panel is made up of a layer of silicon cells, and when those cells interact with light, they cause electrons to be set into motion, which initiates the electric current.
As long as sunlight is hitting a solar panel, it will generate electricity — no matter how cold it is.
In actuality, colder temperatures can help improve the performance of solar cells! Unless your solar system is blocked by shade from trees or snow (which should be cut back or cleared), it will continue to absorb energy during any sunny day, even in the winter. Even light snow or ice will not be an issue as sunlight is still able to pass through to the solar panels. Moreover, the dark cells of solar panels are engineered to absorb heat from the sun. If a small portion of a solar panel is exposed to sunlight, heat can spread throughout the solar panel facilitating the snow melting process. Along with a smooth surface and the slanted angle of the panels snow, often naturally melts and slides off.
However, as we’ve seen all too often, ice and snow can bring down power lines, leaving those they were delivering electricity to without until crews can get to the lines to restore them, which, depending on location and the weather, can take days, or longer.
That level of reliability for our power system, regardless if it's fueled by natural gas, coal, wind, solar or even with some storage, is not enough… you need to put the generation and the reliability at your homeJohn Berger, CEO Sunnova Energy
Quality residential solar systems like ours are built to last over 25 years and are designed to withstand freezing temperatures. And they can bear the weight of heavy amounts of snow or debris. Considering that people drive on solar panels, the weight of the snow will not be an issue!
Do solar panels work when the grid is down?
MYTH: Home solar does not work during a blackout
FACT: With solar battery storage, it does – See this
If your home solar system is connected to your utility and you do not have a battery, your home solar system will not work during a grid outage. You will not be able to produce or consume solar energy while the grid is down.
During a power outage, your home solar system will automatically turn off. This is a safety measure to prevent solar energy flowing through the utility grid while repair crews fix any downed power lines or other failures. When the power comes back, your home solar system will automatically turn back on.
This is why it is critical to have battery storage with your home solar system!
When connected to a home battery backup, your solar panels automatically send any excess energy to the battery for later use, such as at night or during a blackout. So during extended power outages, your most needed lights and appliances will be powered by your solar panels and battery, even when the days are dark and stormy as long as some sunlight reaches your panels.1
When the grid is down:
- A battery can power your essential lights and appliances.1 When your battery is installed, you may be asked to choose “critical energy loads” that are most important to power during a power outage, such as your refrigerator to avoid food spoilage, Wifi to stay connected, and your garage door opener to make sure you can get your car in and out . Your battery will be connected to the critical loads.
- Your solar panels can keep generating power from the sun. There is no risk of sending excess solar production to the grid since excess solar production will charge the battery.
How Long Will A Home Battery Backup Last?
Judging the expected life of the battery works similarly to any backup power solution and depends on the amount of energy stored, as well as what it is powering. The larger the power consumption, the less time your backup power supply will last. To get an idea of how long a battery will last, take a look at our battery duration calculator.For more information on Sunnova SunSafe home solar + battery storage, visit our Knowledge Center, or request a no-obligation quote.
Home Battery or Generator… Which Should I Choose?
MYTH: A generator is all I need during times like these
FACT: A generator may not be enough to help you in times like these
Generators and batteries are both good options for resiliency during a power outage. However, there are definitely some things to consider when making the decision on which is best for you and your family.
All backup power solutions need a fuel/energy source to run. Whether it is a solar panel converting sunlight into usable energy for a home or a generator needing diesel, gasoline or natural gas to run. While generators provide backup power during outages, they also still rely on fuel, which could be costly. Also, in extreme weather situations when roads are inaccessible and stores and gas stations closed for prolonged periods of time, if that fuel runs out you may be out of luck. With a solar + battery storage system, however, the power source is the sun – so your panels can continue to generate solar energy and recharge your battery with clean, renewable energy as soon as there is enough sunlight, even if it is not full sun. Check out the chart below for more detail.
And for the greatest reliability in times of crisis, we recommend having both, if possible. When it comes to safety, it’s never a bad idea to be prepared and diversified with your energy solutions.
Learn more about adding a home battery back to your current home solar system here.
Are Renewables in General a Reliable Source of Energy During Times of Crisis?
The better question actually should be, “Is the grid a reliable power source in times of weather emergencies or other crises?”
You see, there are a lot of myths around the inability of renewables to handle rough winters like this one. Yes, wind turbines may freeze up, and solar farms may become snowbound, but the same issues occur with natural gas, coal and nuclear plants.
The issue with relying on the grid is one of transmission from the fuel source to your home and the infrastructure that supports that, regardless of whether the power is coming from a wind farm, a solar farm, or a nuclear generator.
The simple (and perhaps obvious) truth is, installing solar panels and battery storage at your home reduces your need to rely on our nation’s aging power grid and its ability to transmit energy. Instead, clean, renewable solar energy is produced and consumed right at your home.
As a leading residential solar power and storage service provider, we strongly feel the current discussion shouldn't solely be about renewables vs. fossil fuels – it should be about the viability of distributed generation and how we can bring consumers the most affordable and reliable energy, especially in times of shortages and outages as we are now. How we approach this solution is crucial.
These times of difficulty remind us that we are all part of a community. We must protect those of us who are vulnerable, whether it’s due to age, poor health, and/or low income, by providing resilient and reliable energy for all.
As technology advances, it becomes our job to create and provide energy solutions that empower individual users without needing to rely on a centralized monopoly that cannot always deliver.
This is not a renewables vs. fossil fuels issue, it is an issue of an aging grid, transmission, and distribution structure that is becoming increasingly unreliable, and for that, decentralization is the answer.
At the end of the day, this is about bringing consumers the best service with the most efficient technology, the most reliable fuel source, at the best price.
1. The amount of power available from the battery during a power outage is limited, depending on the loads connected, customer usage and battery configuration (i.e. batteries in certain areas may be set up to provide you with the best economic benefit, which may affect the amount of back-up power available). Solar systems and/or batteries may require repairs after weather events and such repairs may be delayed due to forces outside of our control. No assurances can be given that the solar system or the battery will always work. You should never rely upon either of these to power life support or other medical devices.