Severe storms leading to power troubles might have come up with the question – “What will happen to solar energy if the power goes out?” Well, the response is very straightforward. Solar power will never act as a backup generator. Solar energy will go out similar to other energy forms during a severe storm. Thus solar panels will not be able to work by themselves during a power outage but if it is paired with solar battery storage, they will be helpful.
So let us find out how solar panels work, what happens at times of power outages and whether a backup system is absolutely essential.
How does the solar energy system work?
Solar energy comes from solar panels. The panels absorb energy from the sun to form direct current (DC) electricity. But since most houses and establishments run on alternate current (AC), DC electricity is changed to AC electricity by an inverter. Once the conversion is done, it powers your homes. So it is quite evident that solar panels cannot work as a backup if AC electricity goes off due to any reason including bad weather.
Do solar panels work during a power outage?
Ordinary grid-tied solar will not work during a grid failure and there are two reasons for it. The first reason is technical while the second is entirely a safety and regulatory issue.
First, let us talk about the technical reason. The electronics controlling a solar system changes current and voltage constantly so that the panels operate efficiently with the change in sunlight. For this, the system will produce power quantities that do not depend on the actual usage of your house at that point in time. In the case of a grid-connected system, excess power is sent back to the grid so that the others can use while your utility credits you on your bill for that power.
The output of solar power is directly variable with the levels of sunlight and so connecting this variable resource to the electrical system of your home directly would result in the blinking of the lights, wreaking havoc on your television and computers and damaging your refrigerator.
The second reason for solar shutting down during a blackout is safety. Whenever there is a power outage, repair crews are sent out by the power utility to locate and fix the points of failure. Linemen will be at danger if a local power generator like a solar system is adding power to the grid lines. So as per utility rules, solar arrays must shut down automatically whenever there is a power outage. So solar systems are equipped with detectors that find out whether power is coming through the grid and whenever they find that the grid power is down, they shut down automatically too so that the utility workers are not harmed.
Why do I need a solar battery during a power outage?
Once the electric grid shuts down due to extreme weather conditions or other reasons it will include your solar panels. The reason for the shutdown is to protect the linesmen. Again the solar system panel is connected to the grid through a solar inverter which runs to a meter that records your energy usage and the excess energy you contribute to the grid. So with the shutdown of the grid, the solar panels hang up.
In these conditions, the only way your solar panels will continue generating power is through solar battery storage. Thus solar storage has become a necessity today and is becoming an integral part of the infrastructure of renewable energy.
Can you go for a battery backup?
You can install backup batteries as this will act as a backup system at times of power outages. But here you will have to consider the cost-effectiveness. The cost to benefit ratio might not be good enough. Also, such backup systems require significant maintenance and replacement after every 7 – 10 years. But the Tesla Power Wall has come up with new prospects that may be explored.
Is Battery Backup a good idea?
Battery storage for PV solar systems has arguments both for and against it. The ‘for’ argument is that the battery backup will enable your business or home to run during a blackout. While the biggest ‘against’ of battery storage is the cost which might be double the cost of your clean energy system. Batteries are toxic and difficult to discard after usage and thus compromise the ‘clean energy’ perspective of solar energy. Also, batteries have a short life as compared to the solar system components. They are bulky and heavy too and need lots of maintenance for performing the best. So it often happens that people simply stock on candles or buy a flashlight.
But if you are residing in an area where there is a frequent power outage, backup power becomes a necessity and not a luxury. You might also need to keep certain medical equipment always on the roll 24 x 7. If such is the case, battery backup is definitely something you can look out for. But if you are living in an area that does not have frequent outages, think twice before investing in a battery backup.
Are you in need of a back-up battery system?
You will need a backup battery system if you –
- Experience frequent power outages
- Have critical appliances in your home
- Feel comfortable with the knowledge that you will have endless energy even when the grid is down
- Experience extreme weather conditions
How to power through blackouts with a solar battery?
You can power through a power outage with a reliable solar battery and control the energy storage. The excess solar energy of the panels is diverted to the battery and backup panel to power the useful appliances and the most utilized rooms of your house.
Though generators offer a temporary solution during blackouts, yet they depend on fossil fuels and can prove to be quite disruptive. With a solar battery, you have the opportunity to store energy in a green and clean way which can come useful at times of power outage. The batteries store the electricity produced by the solar panels in the daytime so that they can be used at times of need.
What is the right size of your backup system?
If you need total home backup, it would be a good idea to call solar designers who will analyze the electric use patterns of your home and likewise make recommendations to keep all the loads running. At times, an upgradation to your electric panel may be required and this might be quite useful at times of power outages.
But if the electrical situation in your home does not need whole home backup, you can backup certain essential loads.
How are new Inverters useful at times of power outage?
New inverters provide a partial solution to the grid power failure problem as they come with a secure power supply (SPS) that can connect to an external socket outlet. They can supply 1500W of daytime power as the sun shines and the array generates enough power when there is a grid outage. This system will supply a small amount of electricity even when the grid is out and the other solar PV systems are down. Thus this new technology will be able to provide a limited amount of electricity to your business or home during a power outage. Also, these new inverters address the safety and technical issues by forming a small, independent circuit totally disconnected from the grid.
The inverter controls the electrical output of the solar panel and is an alternative to sending out changing power levels.
Why is solar given significance for addressing blackouts?
Solar has been given prominence for addressing blackouts as it is equally effective for both businesses and homes. Many homes require a “critical load” which is the power requirement in twenty-four hours in a day due to the medical concerns of a resident. Blackouts can prove to be detrimental to such load energy users. For them, it can become a case of life and death. With solar panels and proper backup, such difficulties can be overcome.
Moreover, solar power can be a lifesaver as extrasolar panels can take the place of the grid at times of crisis.
What is the preferred backup – generator or battery?
To give a rational response, it would be wise to study the pros and cons of both situations.
Pros of Battery Backup
- Quiet operation
- Uninterrupted power backup
- Least maintenance cost
Cons of Battery Backup
- Sized to provide back up of only essential appliances
Pros of Generator Backup
- More economical
- Sized typically to back up your entire home
Cons of Generator Backup
- Noisy operation
- Does not provide an uninterrupted supply
- Needs refueling and requires maintenance
With all this information, it is for you to choose whether you would like to go for a backup system and if so, the preferred one!