Why doesn’t my Solar Power work if the utility goes down? – by Brian Milholland

San Diego has installed more than 37 Megawatts of Solar to date. A solar system that produces more energy then is used generates what is known as excess energy. This excess energy must have some place to go. This excess energy goes directly into the utility grid. The stored excess energy is then drawn back for use at a later time by the producer.

First of all, a safety issue exists for grid connected solar.  Due to, if power were to feed onto the grid at a time that the utility was shut down.

Therefore, to prevent this, inverters are required to be “utility interactive.” This means they must sense utility power before they produce their own power and feed onto the grid. Most noteworthy is if the utility goes off so does your Solar Power.

Still, people would like to have the security of being able to generate some power if the utility goes down. Especially relevant if they installed solar. So, if the sun is shining, technically the panels are producing power, why don’t I have access to this power?

What is a Secure Power Supply?

Now an Inverter manufacturer “SMA” has answered this call. They have a series of inverters with a “Secure Power Supply” that provides up to 1500 watts of power during the day in case of a grid outage.

We install a switch and a standard 120 volt outlet at the inverter. Therefore, in the case of a grid outage you simply toggle the switch on and the outlet becomes powered. Hence, the inverter regulates the power based on availability from the solar array during the day. Finally, it will shut down if it can’t provide the power requested by the devices you have plugged in.

When grid power returns you simply toggle the switch off and the inverter returns to normal use.

What about Battery Backup for my Solar?

With battery backup, your home or business can be powered during a blackout. In the event of a power outage, basic habits such as charging a cell phone or powering a small fan can become essential. Most homeowners have no source of backup power when the grid goes down. Even homes with solar may lose power in the event of a grid outage if their system does not include some form of energy storage. Battery technology has become far more efficient and inexpensive with lithium ion batteries. Be sure to look into both systems, as each one has its own benefits. Contact us for current information regarding Battery Backup for grid tied Solar systems.

To learn more about these Secure Power Supply Inverters. Consequently, that allow power generation when the grid is down.  Contact us at 858 541-1097 or click the contact us link and send us a message.


brian milholland solar powerBrian Milholland is the president and owner of Milholland Solar  Electric & Roofing. As a native Californian, Brian worked in the construction industry while in high school. He learned residential and commercial wiring while in the army. Trained as a helicopter electrician. Brian served in that military occupation for three years. After leaving the army he worked for two years as a foreman for an electrical contractor before getting his California Electrical Contractors License. Brian brings over 30 years of experience in everything electric with a special expertise for designing and installing Solar Power Systems. As a NABCEP certified & licensed C-10 and C-46 and C-39  Contractor, you could not be in better hands.