Solar Power/Stanby Generator

[joeyman008]

Home owner question?? We are installing both solar and a stanby generator. When the grid goes down, can the solar and standby generator work together to power the house? If it can how should it be wired? Do I need a special transfer switch?

 

[LarryFine]

Joey, this is not as simple as you may believe it is. You need a comprehensive controller, not a simple transfer switch.

This kind of system MUST be designed by someone who has the knowledge and experience.

 

[joeyman008]

Is there a manufacturer that you may suggest that may have the controller.

 

[iwire]

Joey, this is not as simple as you may believe it is. You need a comprehensive controller, not a simple transfer switch.

This kind of system MUST be designed by someone who has the knowledge and experience.

Excellent post. :smile:


Joey, is the system going to grid tied during normal conditions?

If so it gets very complex and the power company will be very strict about how this will be done.

I am working on three grid tied solar systems right now and the power company will not even accept the application without a engineers stamp on the drawings.

 

[dbuckley]

You've got solar and grid, so an inverter is probably in the mix, and many inverters can have a genset connected which they will then manage the whole problem. So the solutions are out there but heed the advice from the other posters above.

 

[joeyman008]

Yes the solar power is Grid tied! Is it possible that when the grid does down the solar power and the standby generater, can work together in supplying power?

 

[BigDon]

Every situation is different; I'm trying to understand what you're planning to do. It sounds like your asking if you can use a generator to supply some loads, and the PV to supply other loads in the house. Is this what your asking? Do you have particular DC loads in mind, such as landscape lighting?

Typically, however, if you have both solar and a generator, you use the solar to charge batteries through a charge controller. When the grid fails, the batteries supply the load through an inverter while the generator starts. Once the generator is ready, the batteries are no longer needed.

 

[brian john]

I am working on three grid tied solar systems right now and the power company will not even accept the application without a engineers stamp on the drawings.

Just One stamp? The utility around here was tough as nails and would hardly ever approve even after all the foot work was completed. I have not been involved in this for a while so I aam not sure if their attitude changed.

 

[bkludecke]

What size generator and what size solar array? If the generator is too small or not compatible the inverters could destroy the generator. Be careful.

I'm doing a similar installation with a wind turbine and have elected to install a lockout relay to keep the wind turbine shut down during a power outage. Outages around here are usually short lived and it's just not worth the grief to jepodize the generator (22kw) with the output of the wind turbine (24kw).