Do you know that your solar power installation is programmed to shut down during a power outage in the grid? The solar panels installed in your home require a grid connection to work. Although they automatically generate electricity, your solar panels will not feed electricity into your home when there is no power in the grid. Your inverter may be programmed to shut down during a power outage for many reasons. Read on to know why it is so and how to use solar panels during a power outage.
Why do the solar systems shut off during power outages?
It seems a bit strange. Most people install solar panels to power their homes when the grid power shuts down.
Unfortunately, it doesn’t work that way. And, there is a valid reason for it as well.
Industry experts say that solar energy systems are designed to shut off during grid power outages for safety issues. When the grid power shuts down and if the solar system continues to generate power and feed electricity into a switchboard that is also connected to the grid, the solar power will flow back into the grid. Grid-tied solar systems attached to a smart meter are designed to handle electricity flow in both directions.
The solar installations would feed power back into the grid lines that are damaged or malfunctioning, the original reason for the outage. In case a utility employee is carrying out repairs to the grid, the backflow of electricity can be fatal. This can lead to severe burns and injuries due to the presence of the live voltage in the disrupted power lines.
To avoid such mishaps, the inverter is designed to cut off solar energy production in the event of a power outage in the grid. In practical terms, you will be left with no power, even if your solar energy system can generate electricity.
This might make you wonder if installing solar panels on the roof is a good idea at all. What is the point of having it when it is not useful when you want it the most? There has got to be a way out. Isn’t it possible to design the system in such a way that the backflow of solar energy into the grid can be prevented? Or better still, you may be able to draw power from the stored electricity in a solar battery.
Let’s see how we can overcome this situation and help you draw from the power generated by your solar installation.
Ways to use solar power when grid power goes off
Here are the choices available to you to continue drawing power from your solar panels during power outage.
- Include solar batteries in your solar system
- Install a solar-powered generator
- Use an inverter that will not allow the backflow of electricity
One of the cost-effective options to manage the power crisis during grid outages is a gas-powered generator. As you guessed, this has got nothing to do with solar energy. This generator runs on gas and can generate sufficient electricity to power your home for a short period when the grid is down.
Unfortunately, this is not an eco-friendly arrangement. The racket it makes, the smell of burning gas, and the air pollution it creates make it less than desirable. Moreover, a backup generator doesn’t use solar energy.
Let’s go back to the list mentioned above and see how we can make available energy generated by solar panels during power outages.
1. Solar battery
Nothing is simpler than installing a solar battery to resolve the dilemma. Moreover, the transition from grid power to backup battery power is seamless and without fuss.
Solar batteries store the excess electricity generated by your solar panel system. If you install a solar system and a solar battery with the right capacity, this would provide you with uninterrupted electricity when the grid power supply goes out.
At the time of purchase, you need to account for this eventuality. The solar system needs to have sufficient solar panels installed with accessories to generate excess power when the sun is shining. The battery must also have the capacity to store enough electricity to cater to your power needs when the grid power is not available.
Solar batteries come in a wide range of designs that have a big say in their ease of use.
The least expensive of them is the lead-acid deep-cycle battery. This type of battery may be crude in its appearance but does its job effectively. These are designed to be recharged and discharged multiple times. The batteries won’t get damaged even if it discharges completely.
At the other end of the backup battery spectrum is the Tesla PowerWall. Sleek and efficient, the PowerWall can keep you going for days together without grid power. In between these two comes a variety of batteries in terms of price, efficiency, and looks. Naturally, the more you shell out, the better product you will get.
When you add a solar battery to your solar energy installation, it automatically cuts you off from the grid when the power fails. “Islanding” can help keep the power on at home by drawing energy from the solar battery.
As long as grid power remains off, your home would remain disconnected from the grid with the solar battery generating energy during the daytime and discharging when the sun is not available. If you have a solar battery with a large enough capacity, you can make this arrangement with solar panels work for days.
The only downside to this perfect solution is the price of the solar battery. Whether you are choosing the lead-acid deep-cycle battery or a Tesla PowerWall, it is a costly purchase. Of course, the PowerWall will cost you many times over.
2. Solar generator
If you don’t want to spend so much of your hard-earned money on a solar battery but would still want to use the solar energy to meet your basic needs during a power outage, a solar generator may be the answer.
Solar generators cost a fraction of the cheapest among solar batteries. You can buy a solar generator for a couple of hundred dollars. This will keep your small devices and appliances running.
These portable devices collect solar energy through their own solar panels and store it in their built-in battery. The inverter converts the DC into AC before the stored electricity can be used. In fact, it is a miniature all-in-one version of the solar system with a battery arrangement.
Again, the capacity of the solar generator decides how much it can be of use to you during a power outage. The simpler ones can charge phones and small appliances. If you want to use it for bigger appliances, you need to buy one with a higher capacity.
3. Specially-designed inverter
Though solar batteries are good, they are expensive. Solar generators are cheaper but there are limitations in their use. There is another way to keep power in your home during a grid outage.
There are inverters designed specifically to ensure that the backflow of electricity into the grid doesn’t happen. They work by automatically disconnecting from the grid in the event of power failure. At the same time, these inverters will continue to allow the solar energy from the installation to flow within your home.
Enphase Ensemble and SMA Sunny Boy are examples of such special inverters. These inverters are typically installed using a special circuit. All you need to do is to switch over to off-grid when power fails.
However, you need to remember that there is no battery in this arrangement that can store energy. So, this will work only when the sun is shining. Of course, you can add a battery to overcome this problem.
Another point to note is the capacity of this inverter. It may have only sufficient capacity to power essential devices and appliances.
Can it help by going off the grid?
The main purpose of remaining connected to the grid is to access power when your solar installation is not generating electricity. This includes at night and on rainy and cloudy days.
You have the choice to disconnect from the grid and rely entirely on solar energy for your electricity needs. Since a solar system can produce energy only when the sun is shining, you may need a battery of sufficient capacity to meet your energy needs when the sun is down.
When you are no longer connected to the grid, power outages won’t have any adverse effect on you. Your solar system would continue to supply power.
This can be a costly exercise as you need a high-end battery to provide power when the sun is not shining. In case you live in a place with long winter months with no sunshine for days together, you would be forced to resort to gas-powered generators to bridge the gap.
In comparison, a grid-tied arrangement is much cheaper, though it comes with its own challenges.
Bottom line
Power outages are becoming more and more common in recent years due to extreme weather conditions like hurricanes and flooding. Instead of waiting for these eventualities and suffering the consequences, you can prepare in advance in whichever way you think is suitable.
It is vital to have some backup power supply arrangement to deal with these situations. Buying solar panels is indeed a good choice but it may not come to your aid when you need it most unless you make extra arrangements.
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