If you want to have something from Lightning components trigger an email, you have some options.
When a record is saved, you can use a workflow rule to trigger sending an email. If the save is done as a result of your component, then great. It still works.
Here you don't have to depend upon a record save. You can arbitrarily send email. But you are required to abide by the maximum outbound email limit.
Callout to External Email Service
Again, this is via Apex, but instead of using our email service, you could make a callout to an external email provider.