How do I automatically back up my photos from my phone to Google? Last time I checked, many months ago, or a year maybe, whenever I took a photo with my Android phone, it would back up to Google Plus. Although I didn't want my pictures to be shared on G+, I did like that every photo was being automatically uploaded in case something happened to my phone.

Within the last week, I had to reformat my phone. Unfortunately, it was only after that I discovered that Google has made some changes. There is now a separate Google Photos service, separate from Google Plus. It seems now that my Google account has not been automatically uploading my photos. So, everything that was on my phone is now gone. Which sucks.

I tried to see if there was an option with the new Google Photos or Google Drive or somehow to make it so my phone automatically uploads pictures I take for backup, but I can't find any such setting.

Is it possible to automatically backup photos with my Google account?

Note just in case someone suggests it, I'd like to not use Dropbox for a variety of reasons that aren't worth going into here. So, please, only suggestions that utilize my Google account if possible. Thanks.
Actually Google Photos app does allow Auto backup of your photos onto Google, and the best part is that there is no Storage limit on it, i.e. you can upload unlimited images and videos.

All you need to do is, 
Open Photos app and slide the navigation drawer from the left.
Select Assistant and you will be able to see that your photos are being backed up.